suggests malabsorption (with frequent bulky, foul smelling stools) Investigation of malabsorption stool consistency, p...
- suggests malabsorption (with frequent bulky, foul smelling stools)
Investigation of malabsorption
- stool consistency, pH, reducing substances, microscopy, occult blood
- stool: O & P, C & S, C. difficile toxin, 3-day fecal fat
- chest x-ray
- urinalysis
- FBC, differential, ESR, smear, electrolytes, total protein, immunoglobulins
- absorptive and nutritional status: albumin, carotene, Ca, PO4,Mg, Zn, Fe, ferritin, folate, fat-soluble vitamins, PT, PTT
- sweat chloride
- if indicated, a-antitrypsin level, thyroid function tests, urine Vanillylmandelic Acid (VMA) & Homovanillic Acid (HVA), HIV test, lead levels
- upper GI series + follow-through
- specialized tests: small bowel biopsy, endoscopy and biopsy
1. Intestinal Causes
Celiac Disease (Gluten-sensitive enteropathy)
- defect at the mucosal level (BROW: barley, rye, oats, wheat)
- toxic or immunologic reaction
Clinical features
- presents at any age, usually 6-18 months
- FTT with poor appetite, irritability, apathy
- anorexia, nausea, vomiting, edema
- wasted muscles, distended abdomen and flat buttocks
- anemia, bleeding
- rickets
- clubbing of fingers
Diagnosis
- fat malabsorption studies
- small bowel biopsy: flat atrophic mucosa with resolution
- after trial of gluten-free diet (villous atrophy)
- antigliadin, antiendomysial antibodies, low D-xylose absorption
Treatment
- gluten-free diet for life
- avoid BROW
Complications if untreated
- small bowel lymphoma
- malnutrition
Milk Protein Allergy
- immune-mediated mucosal injury
- can be associated with soy protein, anemia, hypoalbuminemia
- often atopic individuals
Inflammatory Bowel Disease
- see Gastroenterology lectures
- incidence: increasing in North America, mostly older children, teenagers
Other
- specific enzyme deficiencies
- liver disease,
- biliary atresia
- a-Beta-lipoproteinemia
- short gut syndrome
- blind loop syndrome
- protein-losing enteropathy (Celiac, IBD, Giardia)
2. Pancreatic Insufficiency
Cystic Fibrosis (see Cystic Fibrosis lecture)
- loss of exocrine pancreatic function
Clinical features
- meconium ileus in the newborn
- FTT with good appetite
- rectal prolapse
- steatorrhea
- respiratory symptoms, nasal polyps
Diagnosis: elevated sweat chloride (> 60 mEq/L), increased fecal fat,DNA mutation
Management (GI)
- pancreatic enzyme replacement
- fat soluble vitamins (A,D,E,K)
Shwachman Syndrome
- pancreatic insufficiency (autosomal recessive)
- cyclic neutropenia
- skeletal abnormalities (metaphyseal dystosis leading to short stature)
- Dry skin, eczematous, chthyosiform lesions
3. Diet-Induced
- food allergy
4. Other
- diets rich in sorbitol, fructose (poorly absorbed CHO)
- metabolic/endocrine
- thyrotoxicosis
- Addison's disease
- galactosemia
- immune defects
- IgA deficiency, hypogammaglobulinemia
- SCID
- AIDS
- neoplastic
- pheochromocytoma
- lymphoma of small bowel
