Persistent Diarrhoeaã The Trustee of the Wellcome Trust 1998Reviewed by: Dr R H Behrens, Hospital for Tropical Diseases, London, Dr R J D Moy, Institute of Child Health, The University of Birmingham and Dr W A M Cutting, Department of Child Life and Health, The University of Edinburgh, UKPicture: A Bangladeshi child before (left) and after (right) persistent diarrhoea. Note the severe malnutrition.Copyright Images from Behrens RH.Image references ################ .\IMAGES\T45345d.jpg Contents Click on the underlined text to jump tothat screen. Screen 3 Objectives 4Introduction 6Epidemiology 13 Assessment 14 Aetiology 20 Assessment 21 Clinical Assessment and Laboratory Diagnosis 29 Assessment 30 Treatment 42 Assessment 43 Tutorial Assessment 44SummaryUnderlined text is interactive. It indicates that further information is available. Click on the underlined text to view the information. Small bowel histology of a Gambian child with persistent diarrhoea-malnutrition syndrome. Note the grossly blunted villi. Copyright Copyright Image from Behrens RH.Image references ################ .\IMAGES\T45340.jpg Objectives At the end of this tutorial you should be able to: 1. define persistent diarrhoea and describe its epidemiology 2. summarize the aetiology of persistent diarrhoea, in particular its close relation with malnutrition 3. describe the clinical assessment of a child with persistent diarrhoea and the role of laboratory diagnosis 4. review the management of a patient with persistent diarrhoea Image references ################ Introduction - 1 Diarrhoea Diarrhoea is: · an increase in the number, volume and water content of stools · a global cause of much illness and death· a major factor in childhood malnutrition This tutorial is about persistent diarrhoea, which is an important cause of malnutrition and death in the developing world. Picture: A child with persistent diarrhoea in Bangladesh being examined. He is lying on a cholera cot.Copyright Image from Behrens RH. Diarrhoea morbidity and mortalityEach year there are: · approximately 3.3 million deaths due to diarrhoea, 80% in children under 2 years of age · over 1 billion episodes of diarrhoea, most in the developing world · 5 - 10 million travellers affected by diarrhoea, 3% of whom have persistent diarrhoea Image references ################ .\IMAGES\T45353.jpg Introduction - 2Persistent diarrhoea and malnutrition Persistent diarrhoea is: · a major cause of malnutrition in developing countries · much more common in children with pre-existing malnutrition These interactions set up a ‘vicious circle’ (see picture). How does persistent diarrhoea reduce nutritional status? Death in a child with persistent diarrhoea is: · strongly associated with malnutrition · usually due to associated non-intestinal infections, eg. pneumonia · rarely due to dehydration Persistent diarrhoea Reduced intake and absorption of nutrients Impaired defence mechanisms Malnutrition The link between persistent diarrhoea and malnutrition is so close that they are often considered as a persistent diarrhoea-malnutrition syndrome. Copyright Image from The Wellcome Trust.MalnutritionDuring an episode of persistent diarrhoea, children with pre-existing severe malnutrition are 20 - 60 times more likely to die than are well nourished children. Persistent diarrhoea and malnutrition Persistent diarrhoea worsens nutritional status through: · reduced dietary intake due to: - anorexia - incorrect treatment during the diarrhoea episode · poor absorption and digestion of nutrients due to damaged small bowel mucosa Dehydration Dehydration in children with persistent diarrhoea: · is less common than in those with acute watery diarrhoea · carries a high risk of death and should always be treated in hospitalImage references ################ .\IMAGES\Circdia2.gif EpidemiologyEpidemiology Image references ################ Epidemiology - 1Impact of persistent diarrhoea Infectious diarrhoea presents as three clinical syndromes:· acute watery diarrhoea · dysentery or acute bloody diarrhoea· persistent diarrhoea In children under 5 years, persistent diarrhoea (see pie charts) causes: · 11% of all episodes of diarrhoea· 35% of all deaths from diarrhoea Pie charts: Annual numbers of episodes of diarrhoea and deaths from diarrhoea worldwide. Data from WHO 1995 and Bern et al 1992. Episodes Deaths200 million200 million1.4 billion1.2 million480,0001.6 millionAcute wateryAcute bloody Persistent Copyright Image from The Wellcome Trust based on data from the World Health Organization and Bern C, Martines J, de Zoysa I, Glass RI. Bull World Health Organ 1992;70:705-14.Deaths from diarrhoeaThe data shown probably underestimate the mortality due to persistent diarrhoea. Recent studies suggest that persistent diarrhoea may cause 45% of all diarrhoea deaths. Acute watery diarrhoeaAcute watery diarrhoea: · is loose or watery stools without visible blood · lasts less than 14 days, often less than 5 - 7 days Refer to the tutorial Diarrhoeal Diseases: Acute Watery Diarrhoea. Acute bloody diarrhoeaAcute bloody diarrhoea: · is loose or watery stools with visible blood · lasts less than 14 days, often less than 5 - 7 days Refer to the tutorial Diarrhoeal Diseases: Acute Bloody Diarrhoea. Persistent diarrhoeaPersistent diarrhoea: · is loose or watery stools with or without visible blood · lasts at least 14 days, sometimes 3 weeks or longer Image references ################ .\IMAGES\Diapies.gif Epidemiology - 2 Distribution of the duration of episodes of diarrhoea Definition of persistentdiarrhoea Persistent diarrhoea is defined (WHO 1988) as watery or bloody diarrhoea that: · starts acutely· lasts as least 14 days What proportion of episodes of acute diarrhoea become persistent? A duration of 14 days is taken because the the case fatality rate rises rapidly after this time. For data from a study in rural India. Episodes (%) Data from Black 1993. Persistent diarrhoea Duration of diarrhoea (days) Copyright Image from The Wellcome Trust modified from Black RE. Pediatr Infect Dis J 1993;12:751-61.Acute start to persistent diarrhoea· For practical purposes, the duration of diarrhoea is more important than whether the episode started acutely. · Many studies have defined persistent diarrhoea by duration alone. · Persistent diarrhoea associated with some parasites (eg. Giardia, Entamoeba) often starts gradually. DurationNote how the duration of episodes varies continuously (see graph). A few episodes of persistent diarrhoea last 3 - 4 weeks or even longer. Episodes that become persistent From 3 to 20% of episodes of acute diarrhoea become persistent. This figure varies with different: · definitions of persistent diarrhoea used by different workers · epidemiological and geographical settings · methods of surveillance Case fatality rate of episodes according to duration of diarrhoea Case fatality rate (%) () Episodes (%) () Data from Bhandari et al 1992. Persistent diarrhoea Duration of diarrhoea (days)Image references ################ .\IMAGES\Pddistbn.gif .\IMAGES\Pdcfr.gif Epidemiology - 3 Recurrent acute diarrhoeaEpisodes of acute diarrhoea which are close together can span a total period of more than 14 days. How is such recurrent acute diarrhoea distinguished from persistent diarrhoea?Chronic diarrhoea This is diarrhoea that lasts at least 14 days but is due to non-infectious causes, such as: · coeliac disease (see pictures) · inflammatory bowel disease· hereditary metabolic syndromes · tropical sprue Picture: Stereoscopic views of jejunal biopsies showing normal villi (left) and subtotal villous atrophy in a patient with coeliac disease (right). Coeliac disease is a lifelong intolerance (allergy) to gluten in genetically predisposed individuals. Copyright Images from Behrens RH. Recurrent acute versus persistent diarrhoeaRecurrent acute diarrhoea Day 1234567891011121314 15 Diarrhoea episodes (red) separated by at least 3 days in a row without diarrhoea (yellow) are defined as recurrent acute diarrhoea. Persistent diarrhoea Day 1234567891011121314 15 A 14 day period that contains no more than 2 days in a row without diarrhoea (yellow) is defined as an episode of persistent diarrhoea. Chronic diarrhoeaChronic diarrhoea: · is often gradual in onset · can last for weeks or months · requires specialist gastroenterological investigation and treatment Inflammatory bowel diseasesThe most important of these are: · ulcerative colitis - affects the large bowel · Crohn’s disease - can affect the small and large bowel Subtotal villous atrophyReduction in the height of small intestinal villi is a feature of both: · coeliac disease· persistent diarrhoea Image references ################ .\IMAGES\T45341b.jpg .\IMAGES\Recacute.gif Epidemiology - 4Faecal-oral transmission The pathogens that cause acute and persistent diarrhoea are generally spread by faecal-oral transmission (see picture) through: · contamination of food · faecal contamination of drinking water · direct person to person spread Which factors favour transmission of diarrhoea? Picture: Routes of faecal-oral transmission of acute and persistent diarrhoea. Food Drinking water Person to person Faecal contaminationof hands and clothes Contaminated with faeces Endogenous pathogens Contact, fingers putin mouth Not cooked thoroughly Copyright Image from The Wellcome Trust. Transmission Factors Associated with Acute and Persistent DiarrhoeaEnvironmental factors Host factors Inadequate sanitation Age under 2 years Insufficient clean water Malnutrition1 Poor personal, domesticImpaired immunityand food hygiene Failure to breast feed Crowded living conditions exclusively until age 4 - 6 months Close contact with animal reservoirs1. Malnutrition is associated with an increased duration of diarrhoea and with an increased incidence of diarrhoea in some studies. Refer to the tutorial Diarrhoeal Diseases: Epidemiology.Contamination of foodFood can come to contain pathogens through two main routes. These are: · contamination with faeces containing diarrhoea organisms · natural contamination by organisms infecting animals used as human food Contamination of waterWater becomes contaminated with faeces containing diarrhoea organisms through: · defaecation into or near a water source, eg. a river · rainwater washing faeces into a water source, eg. an unprotected well · a dirty hand or utensil put into stored domestic water Person to person spreadPerson to person contact involves faecal contamination of: · hands · clothes · fomites, eg. a towel Image references ################ .\IMAGES\Foraltsm.gif Epidemiology - 5For picture legend. Risk factors for persistent diarrhoea Persistent diarrhoea is particularly associated with: · pre-existing moderate or severe malnutrition · age less than 6 months · impaired immunity, especially due to measles · signs of vitamin A deficiency · a history of diarrhoea in the previous 2 months · failure to breast feed exclusively How do these factors favour persistent diarrhoea?Copyright Copyright holder unknown. Image supplied by World Health Organization Nutrition Unit, Indonesia (1974). Age less than 6 monthsIn many studies the incidence of persistent diarrhoea is greatest in children aged 3 - 6 months. The peak incidence of acute diarrhoea is generally a little later, at around 6 - 12 months. Refer to the tutorial Diarrhoeal Diseases: Epidemiology. Impaired immunity Immunity, especially cell-mediated immunity, is reduced in children with: · a history of measles in the past 4 weeks · moderate or severe malnutrition · micronutrient (especially vitamin A or zinc) deficiency (see picture) · concurrent infections, eg. pneumonia· human immunodeficiency virus (HIV) infection Failure to breast feed exclusivelyPersistent diarrhoea almost never occurs in young infants fed exclusively on breast milk, for two reasons. 1. Breast feeding strongly protects against acute diarrhoea. 2. Breast feeding during an episode of acute diarrhoea: · shortens the duration of diarrhoea · prevents the episode from becoming persistent Risk factors These factors probably favour persistent diarrhoea through: · increased susceptibility to enteric infections · delayed or ineffective repair of the damaged intestinal epithelium Picture legend Picture: An Indonesian child with severe malnutrition (note the sparse dry hair) and signs of vitamin A deficiency (photophobia). Both are risk factors for persistent diarrhoea.Image references ################ .\IMAGES\T9391.jpg Epidemiology - 6Prognostic indicators of persistent diarrhoea Acute diarrhoea is more likely to become persistent if there is: · visible blood or mucus in the stool (see picture) · a high stool frequency · severe dehydration · consumption of cow’s milk during the episode Which factors predict a lower risk of persistent diarrhoea? Characteristics of severe diarrhoea. Picture: A bloody stool. Acute diarrhoea with visible blood is more likely to develop into persistent diarrhoea. Blood detected microscopically or biochemically is not predictive of persistent diarrhoea. Copyright Image from Bennish M. High stool frequencyMost studies define high stool frequency as 6 or more stools/24 hours. In exclusively breast fed infants: · a soft stool may be seen after almost every feed,4 - 6 times/day · diarrhoea is diagnosed when the mother reports a change in the baby’s stools Refer to the tutorial Diarrhoeal Diseases: Epidemiology. Consumption of cow’s milkThe link between cow’s milk and persistent diarrhoea is strongest in children fed exclusively on cow’s milk during the acute diarrhoea. Consumption of cow’s milk is less predictive of persistent diarrhoea if it is taken: · in smaller quantities, eg. in a partially breast fed infant · mixed with cereals in a weaned child The implications of this for treatment are discussed later. Lower risk of persistent diarrhoeaAcute diarrhoea is less likely to become persistent if there is: · effective antibiotic treatment, eg. against Shigella · exclusive breast feeding in young infants · continued feeding during diarrhoea in older children Image references ################ .\IMAGES\T45899.jpg Epidemiology: AssessmentAre the following statements about X true or false ? Click this button to return to the start of this section. Click on the True or False button for each statement. 1. The first statement, which can be true or false. T (11-pt bold yellow) 2. The second statement, which can be true or false.F 3.The third statement, which can be true or false.T Correct Text explaining the answer (11-pt plain blue) Incorrect Text explaining the answer (11-pt plain blue) Incorrect Text explaining the answer (11-pt plain blue) Correct Correct Incorrect Incorrect Correct Correct Incorrect Incorrect Correct Are the following statements about persistent diarrhoea true or false? Click on the True or False button for each statement. To return to the start of the section. 1. Persistent diarrhoea is an episode lasting at least 14 days with no more than 2 days in a row free from diarrhoea.2. The immediate cause of death from persistent diarrhoea is often dehydration.3. A child is at high risk of persistent diarrhoea if aged under 6 months, bottle fed and malnourished.4. Acute bloody diarrhoea is less likely to become persistent than acute watery diarrhoea.Correct The episode also usually starts acutely. Persistent diarrhoea is different from: · recurrent acute diarrhoea · chronic diarrhoea - due to non-infectious causes Incorrect Text 11 pt Arial dark blue goes here Incorrect The episode also usually starts acutely. Persistent diarrhoea is different from: · recurrent acute diarrhoea · chronic diarrhoea - due to non-infectious causes Correct Text 11 pt Arial dark blue goes here Correct Text 11 pt Arial dark blue goes here Incorrect Death is usually due to associated non-intestinal illnesses (eg. acute respiratory infection) in a child with malnutrition. Dehydration in persistent diarrhoea is relatively uncommon, but serious when it does occur.Incorrect Text 11 pt Arial dark blue goes here Correct Death is usually due to associated non-intestinal illnesses (eg. acute respiratory infection) in a child with malnutrition. Dehydration in persistent diarrhoea is relatively uncommon, but serious when it does occur.Correct Other risk factors for persistent diarrhoea include: · impaired immunity · micronutrient deficiency · a history of diarrhoea Incorrect Text explaining the answer (11-pt plain blue) Incorrect Other risk factors for persistent diarrhoea include: · impaired immunity · micronutrient deficiency · a history of diarrhoea Correct Text explaining the answer (11-pt plain blue) Correct Incorrect Dysentery (acute bloody diarrhoea) is predictive of persistent diarrhoea. Other prognostic indicators during the acute episode include: · high stool frequency · severe dehydration · consumption of cow’s milk Incorrect Text explaining the answer (11-pt plain blue) Correct Dysentery (acute bloody diarrhoea) is predictive of persistent diarrhoea. Other prognostic indicators during the acute episode include: · high stool frequency · severe dehydration · consumption of cow’s milk Image references ################ Aetiology Aetiology Image references ################ Aetiology - 1Models for persistent diarrhoea Three general models for the role of bowel pathogens in persistent diarrhoea have been proposed. Persistent diarrhoea might be due to: · the persistence of an enteric infection by one pathogen · sequential acute enteric infections by different pathogens · a non-infectious bowel complication of long duration secondary to an acute enteric infection Pictures: Pathogens which have been proposed as important in the aetiology of persistent diarrhoea. 1, enteroaggregative E. coli; 2, Cryptosporidium;3, Giardia lamblia; and 4, Shigella. 1 2 3 4 Copyright Image from Knutton S. Copyright Image from Centers for Disease Control and Prevention. Copyright Image from The Wellcome Trust. Copyright Image from The Wellcome Trust courtesy of Hoare CA. Persistence of one enteric pathogen Failure to eliminate an enteric pathogen: · could be due to impaired host immunity or resistance of the pathogen to antimicrobial treatment · is an uncommon cause of persistent diarrhoea, based on isolation of pathogens from stools at different times Non-infectious complications Non-infectious complications that may have a role in persistent diarrhoea include: · lactose intolerance · temporary sensitivity to antigens in cow’s milk, soya and other food proteins · other immune responses Sequential enteric infections When pathogens are isolated from stools at different times during an episode of persistent diarrhoea, it is: · common to find different pathogens at different times · rare to find the same pathogen throughout the episodeImage references ################ .\IMAGES\45926c.jpg Aetiology - 21 Pathogen Association with persistent diarrhoea EnteroaggregativeMore common in E. coli persistent than in Cryptosporidium acute episodes inseveral studies Shigella More common in Giardia lamblia persistent than in Entamoeba histolytica acute episodes insome studies Non-typhoid SalmonellaEqually common in Campylobacter jejuni persistent and acuteEnterotoxigenic E. coliepisodes Vibrio cholerae O1 Rotavirus Less common inpersistent than inacute episodes 1. In some areas (eg. The Caribbean), helminth infections such as Trichuris trichiura and Strongyloides are associated with persistent diarrhoea.Pathogens associated with persistent diarrhoea Studies have isolated stool pathogens and compared the organisms from the first week of diarrhoea for episodes that: · resolved in less than 14 days · progressed to persistent diarrhoea What are the main problems with this approach? These studies show that persistent diarrhoea is associated with: · the same range of pathogens as acute diarrhoea · enteroaggregative Escherichia coli (EAggEC) and Cryptosporidium in particular Which pathogens are isolated frompatients with HIV? Problems with studies of stool pathogensThe main problems with most studies of diarrhoea aetiology are: · failure to isolate any pathogen in 30 - 50% of children · not knowing that an isolated organism has caused the diarrhoea, because asymptomatic excretion of diarrhoea pathogens is commonSimilar pathogens One exception to this generalization is rotavirus, which is: · a common cause of acute watery diarrhoea in children · rarely implicated in persistent diarrhoea Pathogens in patients with HIVPersistent diarrhoea in HIV positive patients is associated with: · Cryptosporidium · pathogens uncommon in HIV negative people, eg. Isospora belli, Enterocytozoon bieneusi and Mycobacterium avium-intracellulare Note that HIV infection, especially in sub-Saharan Africa, is often associated with: · diarrhoea lasting more than 1 month and of complex aetiology · weight loss Image references ################ Aetiology - 3Enteroaggregative E. coli (EAggEC): · is a Gram-negative bacillus · is one of at least five types of pathogenic E. coli · causes bloody diarrhoea by a poorly defined mechanism Cryptosporidium: · is a zoonotic coccidian protozoan · causes watery diarrhoea by: 1. partially invading epithelial cells of the small and large bowel 2. destruction of microvilli, villous atrophy and crypt hyperplasia 3. producing an enterotoxin that causes secretory diarrhoea Picture: Diagnosis of EAggEC. This form of E. coli has a characteristic aggregative pattern of adherence to a monolayer of cultured HEp-2 cells. Copyright Image from Knutton S. Pathogenic types of E. coli Pathogen Characteristic diarrhoeaEnteroaggregative E. coli (EAggEC) Persistent bloodydiarrhoeaEnteroinvasive E. coli (EIEC) Acute bloody diarrhoeaEnterohaemorrhagic E. coli (EHEC) Acute bloody diarrhoeaEnterotoxigenic E. coli (ETEC) Acute watery diarrhoeaEnteropathogenic E. coli (EPEC) Acute watery diarrhoea Mechanism of diarrhoea due to EAggECIn animal models EAggEC: 1. adheres to enterocytes and colonocytes 2. causes an inflammatory bloody diarrhoea characterized by: · haemorrhagic necrosis of villus tips · blunting of villi · elongation of microvilli Villous atrophy Repopulation of the villus with immature crypt like epithelial cells is probably the major mechanism that causes diarrhoea. Refer to the tutorial Diarrhoeal Diseases: Organisms and Pathophysiology.Image references ################ .\IMAGES\T45926.jpg Aetiology - 4Non-infectious intestinal complications Persistent diarrhoea can be precipitated or prolonged by: · lactose intolerance · cow’s milk protein sensitivity · other immune responses Some or all of these may coexist in the same child. Mechanism of osmotic diarrhoea. 1. Bacteria Lactase deficiency Lactose Lactose 2. Gas Short chain fatty acids 3. Osmotic pull keeps water in the lumen Copyright Image from The Wellcome Trust modified from Cutting WA. Diarrhoeal diseases of children in the tropics. In: Lawson DH, ed. Current medicine 4.Edinburgh: Churchill Livingstone, 1994: 133-61.Lactose intolerance1. An enteric pathogen damages the microvilli. This inactivates the brush border enzyme lactase. 2. Undigested lactose builds up in the small bowel lumen. This reduces absorption by its high osmolarity. 3. Bacteria break down lactose into short chain fatty acids. This increases the osmotic load in the lumen and causes an acidic watery stool. Clinically significant lactose intolerance is: · probably a factor in prolonging persistent diarrhoea in some children · much more common in children fed with non-breast milk Cow’s milk protein sensitivityCow’s milk protein sensitivity: · is a temporary allergic reaction to cow’s milk proteins in early infancy · may be triggered by enteric infection or malnutrition · is characterized by persistent diarrhoea and histological changes (subtotal villous atrophy, thin mucosa, moderate crypt hyperplasia, dense inflammatory cell infiltrate) · resolves when cow’s milk is withdrawn but recurs on challenge The importance of cow’s milk protein sensitivity in persistent diarrhoea in developing countries is unclear.Other immune responsesA cell-mediated immune response: · has been proposed as a factor in persistent diarrhoea · is very poorly defined Image references ################ .\IMAGES\Osmodiar.gif Aetiology - 5Histological changes The key feature of persistent diarrhoea- malnutrition syndrome is longstanding damage to the small bowel mucosa. Typical histological changes (see pictures) are:· a thin mucosa · subtotal villous atrophy · crypt hyperplasia · blunt microvilli These findings confirm the: · close link between persistent diarrhoea and malnutrition· aetiological importance of delayed repair of the small bowel epithelium Pictures: Bowel histology in normal small bowel (top) and persistent diarrhoea-malnutrition syndrome (bottom) in Gambian children.Copyright Images from Behrens RH. Longstanding damageHistological changes to the small bowel mucosa can persist well after enteric pathogens can no longer be isolated from the stool.Delayed repair Studies of crypt cell kinetics suggest that persistent diarrhoea-malnutrition is characterized by: · a reduced crypt cell multiplication rate · ineffective maturation of enterocytes as they migrate up the villusImage references ################ .\IMAGES\T45340b.jpg The diagram summarizes the multifactorial aetiology of persistent diarrhoea, but has two gaps. Click your mouse on a box below.Hold the mouse down and drag the correct box to the right place to finish the diagram. Enteric infection Impaired immunity Acute diarrhoea Malnutrition Micronutrient deficiency To return to the start of the section. Persistent diarrhoea Aetiology: AssessmentLactose intoleranceConcurrent infection Age < 6 months Delayed bowel repair Yes. That's right. Yes. That's right. No. That's wrong. Try again. Well done. You have now finished this assessment.Image references ################ .\IMAGES\Pdaetio.gif Clinical Assessment and Laboratory DiagnosisClinical Assessment and Laboratory Diagnosis Image references ################ Clinical Assessment and Laboratory Diagnosis - 1Assessing a child with diarrhoea Clinical examination and a brief history should follow these steps. 1. Assess the degree of dehydration. 2. Establish whether diarrhoea is watery or bloody. 3. Ask about the onset and duration of diarrhoea. 4. Assess for malnutrition and evaluate feeding practices. 5. Determine any concurrent illness and immunization history. Picture: A typical stool from a patient with giardiasis, which is a known cause of persistent diarrhoea. The stool is soft, pale and oily due to a high fat content (steatorrhoea).Copyright Image from Tubbs HR. Assessment of dehydrationClinical assessment should establish the degree of water and electrolyte loss as: · no signs of dehydration· some dehydration· severe dehydration In persistent diarrhoea: · children with any signs of dehydration should be treated in hospital · malnutrition can make assessment of dehydration difficult Refer to the tutorial Diarrhoeal Diseases: Clinical Assessment. Clinical diagnosis of bloody diarrhoeaBloody diarrhoea is diagnosed from at least one of the two findings below. 1. Loose or watery stools that contain visible red blood. This diagnosis excludes: · streaks of blood on the surface of a formed stool · blood detected only microscopically or biochemically · black stools containing digested blood (melaena) 2. A history of bloody stools reported by the child’s mother. Onset and durationPersistent diarrhoea is diagnosed from finding both: 1. an acute onset 2. a duration of at least 14 days Image references ################ .\IMAGES\T22831.jpg Clinical Assessment and Laboratory Diagnosis - 2Questions about feeding practices Infants · Is the child breast feeding? If so, how often? · Was animal or formula milk introduced recently? · Are any other foods or liquids given? Older children · What solid food does the child normally eat? · Is oil added to the child’s food? · How much was the child feeding before the illness? Has feeding during the illness been reduced, increased or unchanged? Why is a feeding history so important? Picture: Breast feeding is important in two ways. It protects from diarrhoea and is an important part of nutritional management in an infant with diarrhoea.Copyright Image from United Nations Children's Fund. In: Diarrhoea, a major public health problem.Save the Children Fund. Taking a feeding historyA feeding history must be taken to be able to advise the mother on: · nutrition during the diarrhoea episode · how to prevent episodes of persistent diarrhoea-malnutrition in the future The questions listed are examples of the sorts of questions to ask. Animal or formula milk If non-breast milk was introduced recently, did the mother notice any change in the stools? The type of milk is important because breast, cow’s and formula milk vary with regard to: · lactose intolerance · sensitizing antigensFeeding during the illnessIf this is a follow-up visit, has the mother seen a change in the child’s appetite since the previous visit?OilIt is recommended that a little vegetable oil be added to cereal to increase its energy content. Image references ################ .\IMAGES\T23774b.jpg Clinical Assessment and Laboratory Diagnosis - 3Marasmus KwashiorkorPhysical examination for severe malnutrition Assessment of nutritional status requires looking for signs of: · severe malnutrition (see picture): - marasmus - kwashiorkor - marasmic kwashiorkor · vitamin deficiency Children with persistent diarrhoea and malnutrition need referral for hospital treatment. Thin, pale weak hair Poor appetite Flakyskin Mildanaemia Apathetic Miserable OedemaNormalhair Hungry Grossmusclewasting Grossly underweight'Worried old man' appearance No fat Large liver Usually underweight Copyright Image from The Wellcome Trust modified from World Health Organization. Readings on diarrhoea. Student manual. Geneva: WHO, 1992.Vitamin deficiencyLeft: Conjunctival xerosis and Bitot’s spot (arrow). The latter are not restricted to vitamin A deficiency. Right: Signs of severe vitamin A deficiency: corneal ulceration. Images from Sommer A. A Fieldguide to the Detection and Control of Xerophthalmia. Geneva: WHO, 1978.Vitamin A deficiency is very important. Ocular features (xerophthalmia - see pictures) include:· a history of night blindness · dry dull areas (xerosis) on the conjunctiva and cornea · foamy material on the conjunctiva (Bitot’s spots) · ulceration and perforation of the cornea in severe cases Severe malnutritionSevere malnutrition increases the risk of death during persistent diarrhoea by 20 - 60 times compared with no malnutrition. Image references ################ .\IMAGES\Maraskwr.gif .\IMAGES\T14039p.jpg .\IMAGES\T14050p.jpg Clinical Assessment and Laboratory Diagnosis - 4Dehydration in a child with severe malnutrition The degree of dehydration is difficult to assess in a child with: · marasmus (see picture) · kwashiorkor Signs that remain useful in assessing dehydration are: · dry mouth and tongue · eager thirst· very dry mouth and tongue · cool moist extremities · weak or absent radial pulse Which other condition can resemble severedehydration? Picture: A child with marasmus and persistent diarrhoea. Signs of some dehydration. Signs of severe dehydration. Copyright Image from Behrens RH. Other conditions resembling severe dehydration In a child with severe malnutrition, the signs of septic shock and severe dehydration are often similar. Both conditions reflect: · a low circulating volume (hypovolaemia) · poor peripheral perfusion A child with severe malnutrition is treated for septic shock if he or she has both: 1. signs suggesting severe dehydration 2. no recent history of watery diarrhoea Dehydration in marasmus The signs of marasmus include: · loose skin from wasting · sunken eyes · child is fretful and anxious These may suggest dehydration even in a normally hydrated child.Dehydration in kwashiorkor The signs of kwashiorkor include: · oedema · apathy and misery Skin turgor and general condition are not reliable signs in the assessment of dehydration in a child with kwashiorkor.Image references ################ .\IMAGES\T45355.jpg Clinical Assessment and Laboratory Diagnosis - 5Anthropometric assessment of malnutrition Diagnosis of Moderate and Severe Malnutrition Weight for Weight forMUACMalnutrition age (%)1 height (%)1 (cm)2 Moderate 60 - 7570 - 8012.5 - 13.5 Severe3 < 60 < 70 < 12.5In addition to physical examination, malnutrition can also be assessed after rehydration from measurements (see table) of: · weight for age· weight for height · mid-upper arm circumference (MUAC) in children aged 1 - 5 years1. Based on US National Center for Health Statistics median values. 2. In children aged 1 - 5 years. 3. With signs of obvious marasmus or kwashiorkor.Weight for ageThis requires that the child’s age is known with reasonable accuracy. This can sometimes be a problem. Weight for heightAn alternative is to measure the length of the child lying down - weight for length.MUACPicture: Measuring MUAC in Rwanda. This method is most useful in emergency situations such as famines.Image from Medicins Sans Frontieres. MUAC is often measured with a tricoloured strip (see picture), which allows classification of the child as: · well nourished · moderately malnourished · severely malnourished Image references ################ .\IMAGES\T45861p.jpg Clinical Assessment and Laboratory Diagnosis - 6Concurrent illness andimmunization Concurrent non-intestinal infections are common causes of death in persistent diarrhoea and must be carefully diagnosed. The most important infections are: · acute respiratory infection, eg. pneumonia · septicaemia · urinary tract infection · otitis media Picture: Immunization for measles in Rwanda. Why is immunization status important? Copyright Copyright holder unknown. Image supplied by MERLIN picture library. Measles vaccination Note that the recommended site for intramuscular injection of the vaccine is the lateral thigh. Concurrent infectionsIn some studies half of all children with persistent diarrhoea have one or more of the four infections listed.Immunization statusEvery opportunity to check immunization status should be taken. In particular, measles is: · preventable by vaccination (see picture), usually at 9 months · a risk factor for severe and persistent diarrhoea · a major cause of death and disability in its own right Image references ################ .\IMAGES\T45823.jpg Clinical Assessment and Laboratory Diagnosis - 7 Laboratory diagnosis Techniques to support the clinical assessment and stool examination are: · stool microscopy for polymorphonuclear neutrophils (PMNs) · stool microscopy for parasites · stool culture for bacterial pathogens · immunological and nucleic acid based methods Are tests of stool chemistry useful? Picture: A trophozoite of G. lamblia shown by high power light microscopy of a stool sample. Note the two nuclei (N) and four pairs of flagella (F). In a child with persistent diarrhoea, this finding is an indication for giving drugs against giardiasis.N F Copyright Image from The Wellcome Trust courtesy of Hoare CA. PMNsA stool sample is stained with methylene blue. A finding of numerous PMNs on light microscopy suggests an invasive bacterial pathogen such as: · Shigella · C. jejuni · non-typhoid Salmonella These pathogens often cause bloody diarrhoea.Microscopy for parasites Light microscopy of a stool sample may identify: · trophozoites of Entamoeba histolytica · cysts or trophozoites of Giardia lamblia (see picture) · oocysts of Cryptosporidium parvum Immunological methodsKits to diagnose G. lamblia infection immunologically: · detect Giardia antigen in a stool sample · are now commercially available Stool culture Picture: Culture of Shigella. Image from Ridgway GL. Culture of bacterial pathogens from a stool sample in selective media: · is often the definitive technique · generally takes 2 - 3 days · requires a fresh stool · is very labour intensive and expensive Nucleic acid based methodsDNA hybridization assays: · can diagnose pathogenic types of E. coli such as EAggEC · are not widely available and are very expensive (A more reliable method for laboratory detection of EAggEC is its adherence to cultured HEp-2 cells - see screen 17).Tests of stool chemistrySimple tests that can be performed on the aqueous phase of the stool include: · litmus tablet testing for stool acidity - pH < 5.5 · detection of sugars at a level above 1% These tests: · can indicate malabsorption of carbohydrate, often due to lactose intolerance· are less useful than clinical diagnosis, ie. the response to withdrawal and challenge with milk Image references ################ .\IMAGES\T2884.jpg .\IMAGES\T45566p.jpg Clinical Assessment and Laboratory Diagnosis: Assessment A child presents with a history of diarrhoea for 16 days. He has muscle wasting with loose skin folds and his weight for age is 55% of the median value. The boy also has a fever with marked chest indrawing. What is your assessment of the boy’s nutritional status? For the answer. Which other illnesses are likely? For the answer.What else should your assessment look for? For the answer. To return to the start of the section. Incorrect Answer: Nutritional status The signs suggest marasmus. The weight for age indicates severe malnutrition. Incorrect Answer: Other illnesses The fever and chest indrawing are consistent with severe respiratory tract infection, eg. pneumonia. (Other possible causes of these signs, such as malaria, should also be considered.)Incorrect Answer: Other things Assessment should also cover: · degree of dehydration · signs of vitamin deficiency · immunization and feeding histories · nature of stools (watery or bloody) · laboratory diagnosis of specific agents as available Image references ################ TreatmentTreatment Image references ################ Treatment - 1 Overview The key steps in treatment of persistent diarrhoea are to: 1. prevent or treat dehydration 2. give oral antimicrobials for diagnosed: - enteric infections - associated non-intestinal infections 3. feed a nutritious diet 4. give supplementary vitamins and minerals (see picture) Where should the child be treated? What are the objectives of treatment? A child with persistent diarrhoea and signs of zinc deficiency. Copyright Image from Behrens RH. Objectives of treatmentManagement of a child with persistent diarrhoea aims to restore: · weight gain · normal intestinal function DehydrationDehydration in children with persistent diarrhoea: · is rarely severe - but if seen is a serious sign · can be treated with oral fluids in the majority of patients Nutritious diet A nutritious diet must be given that: · provides at least 110 kcal (0.46 MJ)/kg body weight daily · does not cause the diarrhoea to worsen, eg. through lactose intoleranceWhere is the child treated?Most children with persistent diarrhoea can be: · treated at home with locally available food · followed up after 7 days, unless their condition worsens Children should be treated in hospital if they are aged less than 4 months or have: · moderate or severe1 malnutrition · serious other infection · signs of dehydration 1. Children with severe malnutrition need specialist management in hospital different from that described in this section. Refer to the tutorial Diarrhoeal Diseases: The Role of Diet and Drugs. Image references ################ .\IMAGES\T25576.jpg Treatment - 2 Management of Dehydration (WHO 1995) Degree of dehydration Treatment No signs of dehydration1 Extra oral fluids athome to preventdehydration andmalnutrition Some dehydration2Oral rehydrationtreatment with ORS solution in ahealth facility Severe dehydrationIntravenousrehydration in hospital 1. Feeding, including breast feeding, should be continued throughout the diarrhoea episode. 2. Breast feeding should be given during rehydration, and solid food restarted after 4 - 6 hours of oral rehydration. Prevention and treatment of dehydration Treatment should reflect the degree of dehydration (see table). This standard therapy shouldbe modified in children withsevere malnutrition. Rehydration in severe malnutrition Incorrect rehydration of a severely malnourished child can cause heart failure due to: · sodium overload or potassium deficiency · overhydration These children should be given: · modified ORS solution (less sodium, more potassium) if they have watery diarrhoea· intravenous rehydration only for hypovolaemic shock Refer to the tutorial Diarrhoeal Diseases: The Role of Diet and Drugs.Extra home fluids More fluids than normal should be given, including: · oral rehydration salts (ORS) solution · extra volumes of the child’s normal drinks · salted drinks · vegetable or chicken soup with salt ORS solution Oral rehydration salts (ORS) solution: · is a solution of salts and glucose of a defined composition that increases absorption · contains electrolytes in concentrations similar to those in a watery stoolImage references ################ Treatment - 3Treatment of enteric infections Antimicrobials should not be routinely given to children with persistent diarrhoea. The only indications for such treatment are: · bloody diarrhoea - treat for Shigella · microscopic detection in a stool sample of: - Entamoeba histolytica trophozoites containing red blood cells (see picture) - Giardia lamblia cysts or trophozoites What is the exception to this rule? Treatment of associated infections Treatment of concurrent non-intestinal infections should follow standard guidelines. Trophozoite Cyst For picture legend. Copyright Image from Liverpool School of Tropical Medicine photo by Stich A. Copyright Copyright holder unknown.Image from Rodhain F.In: Zaiman H.A Pictorial Presentation of Parasites 1986. 5 Day Oral Antibiotic Treatments for Shigellosis (WHO 1994) Children AdultsDrug DoseFrequencyDoseFrequency Ampicillin 25 mg/kg4 times a day 1 g4 times a dayTrimethoprim- TMP: 5 mg/kg Twice160 mg Twice sulphamethoxazole SMX: 25 mg/kga day 800 mg a day (TMP-SMX) Nalidixic acid 15 mg/kg 4 times a day 1 g4 times a day ChildrenAdults Drug DoseFrequencyDoseFrequency Ampicillin 25 mg/kg4 times a day 1 g4 times a dayTrimethoprim- TMP: 5 mg/kg Twice a day 160 mg Twice a day sulphamethoxazole SMX: 25 mg/kg800 mg(TMP-SMX) Nalidixic acid 15 mg/kg 4 times a day 1 g4 times a day Pivmecillinam 20 mg/kg 4 times a day 400 mg4 times a day The choice of drug will reflect resistance of local strains, and availability and cost of antibiotics. Oral Treatments for Amoebic Dysentery (WHO 1994)Children AdultsDrug DoseFrequencyDoseFrequency Ampicillin 25 mg/kg4 times a day 1 g4 times a dayTrimethoprim- TMP: 5 mg/kg Twice160 mg Twice sulphamethoxazole SMX: 25 mg/kga day 800 mg a day (TMP-SMX) Nalidixic acid 15 mg/kg 4 times a day 1 g4 times a day Drug Dose Regimen Children Metronidazole10 mg/kg 3 times a day for 5 days1 Adults Metronidazole750 mg 3 times a day for 5 days11. The duration of treatment is 10 days for severe disease. Treatment is also indicated for clinical failure of two different antibiotics normally effective against Shigella.Oral Treatments for Giardiasis (WHO 1995) Children AdultsDrug DoseFrequencyDoseFrequency Ampicillin 25 mg/kg4 times a day 1 g4 times a dayTrimethoprim- TMP: 5 mg/kg Twice160 mg Twice sulphamethoxazole SMX: 25 mg/kga day 800 mg a day (TMP-SMX) Nalidixic acid 15 mg/kg 4 times a day 1 g4 times a day Drug Dose RegimenChildren Metronidazole5 mg/kg 3 times a day for 5 days Adults Metronidazole250 mg 3 times a day for 5 days Children Tinidazole 50 mg/kg1 Single dose and adults1. The maximum dose to be given is 2 g.Exception to the ruleThe only children who should routinely be given antibiotics are those with severe malnutrition. All severely malnourished children should receive broad spectrum prophylactic antibiotics for 5 days in hospital. One combination is: · gentamicin · ampicillin Refer to the tutorial Diarrhoeal Diseases: The Role of Diet and Drugs. Picture legend Picture: Light microscopy of stool samples showing stages of Entamoeba histolytica. Top: A trophozoite that has ingested red blood cells. This is an indication for drugs against amoebic dysentery. Bottom: A cyst, which is not an indication for such treatment. Image references ################ .\IMAGES\T25124c.jpg Treatment - 4Principles of dietary managementDietary management is central to the treatment of persistent diarrhoea. Feeding should: · provide enough balanced nutrients to: - help repair of the small intestinal mucosa - improve nutritional status · avoid worsening the diarrhoea · include micronutrient supplementation Most children can be fed: · at home· using locally available foods · without intravenous nutritionPicture: Breast feeding during persistent diarrhoea is important, wherever the diarrhoea is treated. Copyright Image from The Leprosy Mission International. NutrientsDietary management of a child with persistent diarrhoea aims to provide at least 110 kcal (0.46 MJ)/kg body weight each day.Avoid worsening diarrhoeaBecause lactose intolerance is a factor in persistent diarrhoea in some children, lactose intake is progressively reduced by: · restricting the intake of animal or formula milk · replacing animal or formula milk with yogurt, which contains less lactose · feeding a diet that is completely free from lactose Breast milk does not seem to induce lactose intolerance, in spite of its high lactose content (7 g/100 ml versus 4.8 g/100 ml for cow’s milk). Breast feeding (see picture) is encouraged because of its beneficial effects. Feeding at home Children should be treated in hospital if they are aged less than 4 months or have: · moderate or severe malnutrition · serious associated non-intestinal infection · signs of dehydration Image references ################ .\IMAGES\T29287.jpg Treatment - 5 Feeding at home Infants should be fed: · breast milk · yogurt instead of animal or formula milk· restricted amounts of animal milk if yogurt is not available Older children should be fed: · milk as described above, according to age · easily digested and nutritious foods (see screen 36) For details of follow-up. Picture: Click on each child for recommendations. Less preferred options. Copyright Image from The Wellcome Trust. YogurtYogurt: · is fermented milk in which some of the lactose has been hydrolysed to glucose and galactose · contains less lactose than cow’s milk· often contains disaccharidases, which promote absorption of carbohydrate Breast feeding infantsInfants of any age being exclusively breast fed should be: · allowed to breast feed as much as they want · encouraged to breast feed more than usual Exclusive breast feeding should be promoted for at least the first 4 - 6 months of life. Infants taking animal or formula milkInfants being fed animal or formula milk should be given: · yogurt by spoon instead, where this is available and culturally acceptable · no more than 50 ml animal or formula milk per kg body weight daily if yogurt is not available Infants below 4 - 6 months taking breast and solids Infants below 4 months taking breast milk and solid foods should be: · encouraged to take more breast milk · fed less solid food as production of breast milk increases Exclusive breast feeding should be promoted for at least the first 4 - 6 months of life.Children over 6 months taking solidsChildren over 6 months should be: · given breast milk (preferred), or yogurt mixed with their cereal · given no more than 50 ml animal or formula milk per kg body weight daily, mixed with their cereal, if yogurt is not available · started on solid foods, if they are not already eating solids, during the diarrhoea episode · given easily digested foods (eg. cereals and vegetables) of high energy and micronutrient content Follow-upChildren being treated at home should be seen again immediately if there is: · worsening of diarrhoea · development of other serious infection or fever Otherwise, they should be assessed after 1 week for: · weight gain · stool frequency Children who have gained weight and have fewer than 3 stools/day should resume a normal diet for age, with an extra meal each day for at least 2 weeks. Image references ################ .\IMAGES\Kidsdiet.gif Treatment - 6Solid diets for home feedingFoods for giving to a child at home should: · be culturally acceptable · be readily available · be high in energy content · provide adequate essential micronutrients · be well cooked · be mashed or ground· contain added vegetable oil Non-breast milk should be given undiluted and mixed with cereal. How often should food be given? Picture: Foods suitable for giving to a child with persistent diarrhoea include cereals and vegetables. These must be prepared properly for feeding to small children. Which other foods can be given? Copyright Image from Chitrabani Society. Other foodsDepending on availability, the following foods should also be given: · meat· fish Sources of animal protein. · egg · bananas · green coconutwater · fresh fruit juice Good sources of potassium. Frequency of feedingThe aim is to coax the child to take as much nutritious food as possible. A child is more likely to take meals given ‘little and often’: · in small amounts · every 3 or 4 hours (at least 6 times a day) Mashed or groundThis makes the food easier for small children to swallow.Mixing milk with cerealMixing non-breast milk with cereal: · improves absorption of lactose by the intestine · reduces the risk of lactose intolerance Added vegetable oilPicture: Adding vegetable oil to food for a child with diarrhoea. Image from United Nations Children's Fund, India. A small amount of vegetable oil (5 - 10 ml): · should be added to each serving of cereal · increases the energy content because fat contains a lot of energy Image references ################ .\IMAGES\T25662.jpg .\IMAGES\T45966p.jpg Treatment - 7Feeding in hospital After any initial period of rehydration: · infants aged less than 4 - 6 months should be fed: - breast milk- yogurt- lactose free formula milk · older children taking solids should be fed: - breast milk as normal - a cereal based diet of defined composition Remember.In infants who would normally take animal milk. Picture: Making up food for giving to children with persistent diarrhoea. Copyright Image from Behrens RH. YogurtIntake of yogurt, by spoon, should be restricted to provide less than 3.7 g lactose per kg body weight daily to avoid lactose intolerance. (Depending on the source, this amounts to daily intake of about 100 ml yogurt per kg.) Cereal based dietsThe first line ‘milk-cereal’ diet contains: · cereal · animal milk or yogurt · sucrose · vegetable oil If this fails, a second line diet is given that contains: · less cereal · no lactose (animal protein as egg or chicken) · glucose · vegetable oil Lactose free formula milkLactose free formula milk: · should be given, by cup, only if yogurt is not available or culturally acceptable · is expensive and not widely available RememberThe recommendations in this section are not appropriate for a child with severe malnutrition. These children need different diets and additional treatments. Refer to the tutorial Diarrhoeal Diseases: The Role of Diet and Drugs. Image references ################ .\IMAGES\T45361.jpg Treatment - 8Diets for Hospital Feeding Click on the columns for an example of each diet. First line dietSecond line diet1 Cereal content High Lower Animal protein2 Cow’s milk or yogurt Egg or chicken Daily lactose < 3.7 g/kg body weight 0 Sugar Sucrose Glucose Energy density3 > 70 kcal/100 g > 70 kcal/100 g1. To be given if treatment with the first line diet fails (see screen 41.) 2. Both diets should provide at least 10% of total calories as protein. 3. 70 kcal is equivalent to 0.29 MJ. How should these diets be given? First line diet: an example (WHO 1995)Ingredient Amount Rice 7.5 g (2½ heapedteaspoons) Milk 40 ml (1/5th of ateacup) Cane sugar (sucrose) 1.5 g (1/3rd of a flatteaspoon) Vegetable oil 1.75 g (1/3rd of ateaspoon) Water to make 100 ml (½ a teacup) Energy density 83 kcal (0.35 MJ)/100 g Recommended daily intake > 130 ml/kgSecond line diet: an example (WHO 1995)Ingredient Amount Rice1.5 g (½ a heapedteaspoon) Egg32 g (1 small egg) Glucose 1.5 g (1/3rd of a flatteaspoon) Vegetable oil 2.0 g (½ a teaspoon) Water to make 100 ml (½ a teacup) Energy density 75 kcal (0.31 MJ)/100 g Recommended daily intake > 145 ml/kg Feeding in hospitalThe aim with either diet is to feed: · little and often, at least 6 times a day · at least 110 kcal (0.46 MJ)/kg body weight daily Children who have had a serious infection: · often feed poorly for the first 1 - 2 days after recovery· may need to be fed by nasogastric tube until their appetite returns Image references ################ Treatment - 9Summary of Diets for Children with Persistent Diarrhoea1 Age At home In hospital Infants up to Breast milk Breast milk 4 - 6 months Yogurt Yogurt Animal orLactose free formula milk2 formula milk Older childrenMilk as above3 Breast milk Cereals, vegetables, 1. Cereal-milk4- vegetable oil;sucrose-vegetable oilmeat, fish, eggs 2. Cereal-egg/chicken- and fruit as available -glucose-vegetable oil For footnotes. Less preferred options Less preferred options Table footnotes 1. The diet should provide at least 110 kcal (0.46 MJ)/kg body weight daily. 2. Limited to less than 50 ml/kg body weight daily. 3. Non-breast milk should be mixed with the cereal. 4. Lactose limited to less than 3.7 g/kg body weight daily (about 60 ml cow’s milk/kg). Image references ################ Treatment - 10 Recommended Daily Allowances ofMicronutrients for a 1-Year-Old RDA Vitamins Vitamin A 400 mg Folic acid50 mg Minerals Zinc 10 mg Iron 10 mg Copper 1 mg Magnesium 80 mg Micronutrient tablets should be crushed and given with food. Micronutrient supplementation All children, whether treated at home or in hospital, should be given at least twice the recommended daily allowance (RDA) of: · the micronutrients listed in the table · other vitamins and minerals as available What is the rationale for micronutrient supplementation? Rationale for supplementationFew controlled trials of the effects of micronutrient supplementation in children with persistent diarrhoea have been performed. In different studies, zinc supplementation caused: · a marginal reduction in stool frequency · improved mucosal function in some children Until more data are available, generous but safe amounts of micronutrients should be provided. Image references ################ Treatment - 11 Follow-up of hospital patients Successful treatment with either diet (see flow chart) is characterized by: · adequate food intake · weight gain · reduction in stool frequency · lack of fever Move through the flowchart with your mouse. When the cursor becomes a 'hand', click on that box for further details.Flow chart: An algorithm for the management of a child with persistent diarrhoea. First line diet Regular monitoring Second line diet Dietaryfailure? No Yes Regular monitoring Discharge with follow-up Dietaryfailure? More specialist management No Yes Copyright Image from The Wellcome Trust modified from International Working Group on Persistent Diarrhoea. Bull World Health Organ 1996;74:479-89. Dietary failureManagement with either diet is judged to have failed if there is either of: 1. a significant increase in stool frequency or recurrence of dehydration at any time 2. no weight gain within 1 week Failure of the first line diet is expected in 20 - 35% of children. Failure to feed due to ongoing non-intestinal infection (including tuberculosis) should be excluded. Discharge with follow-upChildren who respond to either diet should: 1. continue the effective hospital diet for 7 days 2. be given additional fruit and vegetables as soon as improvement is confirmed 3. return home and resume an appropriate diet for age that: - includes milk - provides at least 110 kcal (0.46 MJ)/kg bodyweight daily 4. be regularly followed up to ensure weight gain and good feeding Regular monitoringThe following should be recorded at least daily: · body weight · temperature · food intake · stool frequency Image references ################ .\IMAGES\Pdalgm.gif A 9-month-old boy presents with persistent diarrhoea. He has bloody stools, moderate malnutrition and some dehydration, but no signs of concurrent illness. You decide to admit him to hospital. From the list below, drag the action that you would take into the 'Initial treatment' column. To return to the start of the section. Initial treatment Treatment: AssessmentAntibiotics for shigellosis Metronidazole for amoebic dysentery Broad spectrum antibiotics No broad spectrum antibiotics Oral ORS solution Intravenous Ringer’s lactate Milk-cereal based oral diet Total parenteral nutrition Yes. That's right. Yes. That's right. Yes. That's right. Yes. That's right. No. That's wrong. Try again. Well done. You have now finished this assessment.Image references ################ Tutorial AssessmentAre the following statements about X true or false ? Click this button to return to the start of this section. Click on the True or False button for each statement. 1. The first statement, which can be true or false. T (11-pt bold yellow) 2. The second statement, which can be true or false.F 3.The third statement, which can be true or false.T Correct Text explaining the answer (11-pt plain blue) Incorrect Text explaining the answer (11-pt plain blue) Incorrect Text explaining the answer (11-pt plain blue) Correct Correct Incorrect Incorrect Correct Correct Incorrect Incorrect Correct Are the following statements about persistent diarrhoea true or false?Click on the True or False button for each statement. To return to the start of the tutorial. Persistent diarrhoea:1. is a major cause of malnutrition and death in children in developing countries2. is not always associated with an enteric infection3. should generally be managed in hospital4. must be treated with a lactose free diet in all childrenCorrect Persistent diarrhoea is: · a major cause of malnutrition · more common and more often fatal in children with malnutritionThese effects combine to produce a persistent diarrhoea-malnutrition syndrome. Incorrect Persistent diarrhoea is: · a major cause of malnutrition · more common and more often fatal in children with malnutritionThese effects combine to produce a persistent diarrhoea-malnutrition syndrome. Incorrect Persistent diarrhoea is: · a major cause of malnutrition · more common and more often fatal in children with malnutritionThese effects combine to produce a persistent diarrhoea-malnutrition syndrome. Correct Persistent diarrhoea is: · a major cause of malnutrition · more common and more often fatal in children with malnutritionThese effects combine to produce a persistent diarrhoea-malnutrition syndrome. Correct Enteric stool pathogens: · can be isolated from only 50 - 70% of children with persistent diarrhoea · often disappear well before the diarrhoea has endedIncorrect Enteric stool pathogens: · can be isolated from only 50 - 70% of children with persistent diarrhoea · often disappear well before the diarrhoea has endedIncorrect Enteric stool pathogens: · can be isolated from only 50 - 70% of children with persistent diarrhoea · often disappear well before the diarrhoea has endedCorrect Enteric stool pathogens: · can be isolated from only 50 - 70% of children with persistent diarrhoea · often disappear well before the diarrhoea has endedCorrect Most cases can be managed at home. Hospital treatment is necessary for children aged under 4 months or who have: · moderate or severe malnutrition · serious associated non-intestinal infection · signs of dehydration Incorrect Most cases can be managed at home. Hospital treatment is necessary for children aged under 4 months or who have: · moderate or severe malnutrition · serious associated non-intestinal infection · signs of dehydration Incorrect Most cases can be managed at home. Hospital treatment is necessary for children aged under 4 months or who have: · moderate or severe malnutrition · serious associated non-intestinal infection · signs of dehydration Correct Most cases can be managed at home. Hospital treatment is necessary for children aged under 4 months or who have: · moderate or severe malnutrition · serious associated non-intestinal infection · signs of dehydration Correct A lactose free diet is required only in some hospitalized children. Non-breast fed infants are given lactose free formula milk only if yogurt is not available. Older children are given a lactose free diet only if a first line cereal based diet with restricted lactose content fails.Incorrect A lactose free diet is required only in some hospitalized children. Non-breast fed infants are given lactose free formula milk only if yogurt is not available. Older children are given a lactose free diet only if a first line cereal based diet with restricted lactose content fails.Incorrect A lactose free diet is required only in some hospitalized children. Non-breast fed infants are given lactose free formula milk only if yogurt is not available. Older children are given a lactose free diet only if a first line cereal based diet with restricted lactose content fails.Correct A lactose free diet is required only in some hospitalized children. Non-breast fed infants are given lactose free formula milk only if yogurt is not available. Older children are given a lactose free diet only if a first line cereal based diet with restricted lactose content fails. Image references ################ Summary Click on the buttons below for summary information. Picture: EAggEC adhering to cultured HEp-2 cells. EpidemiologyAetiologyClinical Assessment and Laboratory DiagnosisTreatmentCopyright Image from Nataro JP. EpidemiologyPersistent diarrhoea is infectious diarrhoea that starts acutely and lasts at least 14 days. Risk factors include: · malnutrition (persistent diarrhoea- malnutrition syndrome) · age less than 6 months · impaired immunity · vitamin deficiency · a past history of diarrhoea · failure to breast feed Acute diarrhoea is more likely to persist if there is: · a bloody mucoid stool of high frequency · severe dehydration · consumption of cow’s milkAetiologyPersistent diarrhoea probably reflects: · increased susceptibility to enteric infection · delayed repair to damaged intestinal epithelium Persistent diarrhoea is multifactorial in origin. It is associated with: · many of the same pathogens as cause acute diarrhoea (especially entero- aggregative E. coli and Cryptosporidium) · lactose intolerance · possibly cow’s milk protein sensitivity · histological changes in the small bowel mucosa Clinical Assessment & Laboratory Diagnosis1. Assess the degree of dehydration. 2. Establish whether diarrhoea is watery or bloody. 3. Ask about the onset and duration of diarrhoea. 4. Assess for malnutrition and evaluate feeding practices. 5. Determine any concurrent illness and immunization history. 6. Diagnose specific enteric pathogens according to laboratory facilities available. TreatmentKey steps in treatment are to: 1. prevent or treat dehydration 2. give oral antimicrobials for diagnosed: - enteric infections (shigellosis, amoebic dysentery, giardiasis) - associated non-intestinal infections, eg. pneumonia 3. feed a nutritious balanced diet that: · helps repair of the bowel and improves nutritional status · avoids worsening the diarrhoea by limiting lactose content · includes supplementary vitamins and minerals Section 1 Section 2 Section 3 Section 4 jpg image goes here Copyright Copyright Image from ....... (copyright info) (10 point Arial, blue) Section 1 Pop-up text is in blue with a yellow title in 10 pt bold left aligned.The pop up is a display icon within the library, and if the text is too long then a scroll bar should be used, pop-up boxes can be larger. Section 2 Pop-up text is in blue with a yellow title in 10 pt bold left aligned.The pop up is a display icon within the library, and if the text is too long then a scroll bar should be used, pop-up boxes can be larger. Section 3 Pop-up text is in blue with a yellow title in 10 pt bold left aligned.The pop up is a display icon within the library, and if the text is too long then a scroll bar should be used, pop-up boxes can be larger. Section 4 Pop-up text is in blue with a yellow title in 10 pt bold left aligned.The pop up is a display icon within the library, and if the text is too long then a scroll bar should be used, pop-up boxes can be larger.Image references ################ .\IMAGES\T25755.jpg You have now finished the tutorial Persistent Diarrhoeaã The Trustee of the Wellcome Trust, 1998 Further reading Further activities Restart tutorial Picture: This bottle fed Bangladeshi infant is at an increased risk of persistent diarrhoea.Copyright Image from J Ebrahim Memorial Trust. Further reading Bhan MK, Bhandari N, Bhatnagar S, Bahl R. Epidemiology and management of persistent diarrhoea in children of developing countries. Indian J Med Res 1996;104:103-14. Black RE. Persistent diarrhoea in children of developing countries. Pediatr Infect Dis J 1993;12:751-61. Black RE, ed. Persistent diarrhoea in children of developing countries. Acta Paediatr Suppl 1992;381:1-154. Gracey M. Persistent childhood diarrhoea: patterns, pathogenesis and prevention. J Gastroenterol Hepatol 1993;8:259-66. World Health Organization. Persistent diarrhoea in children in developing countries: memorandum from a WHO meeting. Bull World Health Organ 1988;66:709-17. Further activities To look at pictures related to this tutorial, search the image collection using the following keywords: · clinical features - type of diarrhoea - persistent diarrhoeaImage references ################ .\IMAGES\T37748b.jpg