1. Chronic diarrhea and malabsorption syndromes

2. Definition
Chronic diarrhea: Diarrhea illness persisted more than 14 days, although others use a cutoff of 4 weeks.
Persistent diarrhea is an episode of diarrhea of infectious etiology, which develops acutely but continues for more than 14 days

3. Etiology of chronic diarrhea
Classification according to these two vital factors:- 1- Age. 2- Intraluminal vs mucosal factors.

4. Chronic diarrhea in infants
Common causes:-
Postgastroenteritis malabsorption syndrome
Cow’s milk protein allergy.
Secondary disaccaridase deficiency
Infections as giardiasis and HIV.
Cystic fibrosis.

5. Rare causes Acrodermatitis enteropathica. Primary immune defects
Rare causes Acrodermatitis enteropathica. Primary immune defects. Lymphangiectasia. Eosinophilic gastroenteritis. Intractable diarrhea syndrome. Abetalipoproteinemia. Shwachman syndrome. Bacterial overgrowth. Other rare causes.

6. Chronic diarrhea in older children
Common causes
Chronic nonspecific diarrhea (toddler’s diarrhea)
Postgastroenteritis malabsorption syndrome.
Coeliac disease.
Secondary disaccaridase deficiency.
Infections as giardiasis and HIV. CF

7. Rare causes Immune deficiency. Eosinophilic enteritis. Secretory tumors.

8. Chronic diarrhea in adolescents
Common causes
IBS.
Giardiasis.
IBD
Lactose intolerance
Laxative abuse ( anorexia nervosa ).
celiac
Rare causes
Secretory tumors.
Addison disease.

9. Cont. carbohydrate intolerance
Secondary lactose intolerance (Post infection malabsorption syndrome)
Usually post-infectious ( rota virus).
Bloating, abdominal discomfort and flatulence that occur from 1 hour to a few hours after ingestion of milk or dairy products may signify lactose intolerance.
Stool characteristics: Loose, watery, acidic stool often with excessive flatus and associated with urgency that occurs a few hours after the ingestion of lactose- containing substances is typical.

10. Cont. carbohydrate intolerance
Investigations:
Reducing substances in the stool is positive and the stool is acidic with PH <5.5.
Breath hydrogen test :-
Carbohydrate malabsorption results in bacterial fermentation of the unabsorbed sugar.
Thus, carbohydrate malabsorption can be determined by measuring the exhaled hydrogen concentration after a carbohydrate load is administered.
Management:
Lactose free diet and LF milk

11. Cow’s milk protein allergy
usually starts in the first year when children are given cow milk products.
Symptoms : mild to severe
Typical symptoms are
Vomiting, diarrhea, colic and constipation may occur.
Other rare presentations are wheezes, cough, atopic eczema and behavioral changes like irritability, crying and milk refusal.
A challenge with milk free times may have a good indicators. However, histopathological examination is a diagnostic test.

12. Toddlers diarrhea
Called :chronic non specific diarrhea of childhood (CNSD)
It is a common problem.
1-3 Years
a benign condition.
Usually, the children have no failure to thrive and they present in a good nutritional state. Abdominal pain may be present in a minority.
 The stool is often brown and watery, and contain mucus with undigested food particles. The parents are likely to report a short mouth to anus transit time.

13. Cont. Toddlers diarrhea Golden rules
In developed countries toddler diarrhea is the most frequent cause of chronic diarrhea in 1–5 year old children
Toddler diarrhea has a typical dietary and clinical history
Breath hydrogen tests have no place in the diagnostic process
Rx: .Reassurance,
Decrease Fruit juices.

14. G. lamblia (Giardiasis)
Fecal – oral route
Ingested cysts
Should suspect in children with more than 5 days diarrhea
The diarrhea is voluminous and odoriferous but seldom contains blood

15. cont.
Giardia trophozoite can infest healthy children chronically, but usually this is a clinical problem in debilitated or Immunodeficient children
(selective IgA deficiency are particularly susceptible to persistent giardiasis )

16. Cont. Rare Presentations(diarrhea is absent) : Anasarca
Causes a protracted but usually self-limiting diarrhea in well-nourished, immunocompetent children
Most people who have acute giardiasis become asymptomatic within 6 weeks of onset
Few otherwise healthy children develop prolonged diarrhea with weight loss of 10% to 15%, FTT, and stunting for 2 years or more
Rare Presentations(diarrhea is absent) :
Anasarca

17. Diagnosis Antigen testing of stool
Finding the organism on proximal intestinal biopsy
Clinicians should have a high index of suspicion for giardiasis in children who have:
persistent diarrhea if the
child attends child care
drinks well water
lives near or visits lakes or streams
has lived in or visited underdeveloped regions

18. Asymptomatic children generally are not treated
Treatment Rx
Metronidazole in a dose of 15 mg/kg for 10 days is the current treatment
Asymptomatic children generally are not treated

19. Cystic fibrosis AR disorder.
Most patients have respiratory symptoms as recurrent pneumonia, and adenoid.
Those patients have pancreatic insufficiency which lead to diarrhea with greasy stool.
Failure to thrive.
Genetic diagnosis and sweat chloride test are the main investgations.

20. Acrodermatitis enteropathica
AR disorder,
Presentation
with peri-oral rash, chronic diarrhea, recurrent infection and napkin rash resistant to treatment.
Usually starts at the time of weaning.
Tent red hair and alopecia.
Diagnosis
Serum zinc and alkaline phosphatase concentrations are low
the signs and symptoms resolve after oral or parenteral zinc therapy
Management
Zinc supplements

22. Inflammatory bowel disease
Crohn’s disease and ulcerative colitis.
20% of cases presents under 20 years old.
It has intestinal and extra intestinal manifestations.

26. Cont.IBD Clinical picture Diarrhea Abdominal pain Growth deceleration
Weight loss
Anorexia.
Colonic Crohn disease may be clinically indistinguishable from ulcerative colitis (UC), with manifestations that include the following:
Bloody mucopurulent diarrhea
Cramping abdominal pain
Urgency to defecate

27. Perianal involvement in Crohn disease may produce the following:
Simple skin tags, fissures, abscesses, and fistulae
Painful defecation
Bright-red rectal bleeding
Perirectal pain, erythema, or discharge

28. Cont.IBD Investigations: CBC… anemia. ESR and CRP….. Elevated.
Hypoalbuminaemia.
A single-contrast upper GI radiologic series with small-bowel follow-through (SBFT).
Colonoscopy, bx

29. Endoscopy
Colonoscopy with several colonic and terminal ileal biopsies is considered a standard diagnostic procedure.
Upper endoscopy, or esophagogastroduodenoscopy (EGD), should be part of the first-line investigation.
Video capsule endoscopy is increasingly being used to evaluate for small-bowel Crohn disease in children.

30. Irritable bowel syndrome
chronic or recurrent abdominal pain, altered bowel habits, and bloating, with the absence of structural or biochemical abnormalities to explain these symptoms.
part of a broader group of disorders known as functional GI disorders.
It is the most common GI diagnosis among gastroenterology practices in the United States and is one of the top 10 reasons for visits to primary care physicians.

32. Take care
The following clinical features should alert the physician to the possibility of a disorder other than irritable bowel syndrome (red flags)
Frequent awakening by symptoms
Steady progressive course
Fever
Weight loss
Arthritis
Rectal bleeding
Persistent vomiting.

33. Evaluation of patients with chronic diarrhea
Initially:
Hx and PE
CBC,KFT,Electrolytes, ESR
Stool workup: Ax, Cx, PH, reducing substances, fat
Stool for clostridium difficile toxin
Stool antigen for Giardia lamblia

34. Second phase (guided by Hx and PE):
Sweat chloride,
celiac work up,
quantitative stool for fat (72 hrs collection of stool)
Alpha-one antitrypsin (in stool): for protein loosing enteropathy(PLE)
3rd phase
Endoscopy (U&L), Biopsy
Barium studies