Sunday, May 16, 2010

-Malabsorption syndrome.

Malabsorption syndrome.
Def:-Interference of absorption of one or more of the nutrients from small intestine,however lipids almost always fail to be absorbed leading to steatorrhea (fatty stool).

1)Gastric causes:-
  • Cancer stomach.
  • Atrophic gastritis.
  • Gastrectomy.
  • Gastrojejunostomy.
  • Prenicious anemia.
  • Zolinger Ellison syndrome.
2)Pancreatic causes(decrease Pancreatic enzymes):-
  • Chronic pancreatitis.
  • Cystic fibrosis.
  • Pancreatic resection.
  • Cancer pancrease
  • Hemochromatosis.
3)Hepatobiliary causes:-
  • Liver cell failure(decrease bile salts).
  • Obstructive jaundice(decrease bile salts).
  • Interruption of enterohepatic circulation as in terminal ileum resection or inflammation.
  • Bacterial overgrowth:- which act by deconjugation of bile salts and compete with host for amino acids and vitamin B12.
  • Drugs precipitating bile as:-Neomycin,Calcium carbonate,Cholestyramine.
4)Intestinal causes (the most common):-
A-1ry steatorrhea:-
  • Tropical sprue.
  • Gluten-sensitive enteropathy.
  • Disarcharidase deficiency.
  • Peptidase deficiency.
B-2ry steatorrhea:-
  • Short gut syndrome:-due to multiple bowel resections so decreasing the absorptive surface.
  • Mucosal damage:- by inflammation,Amyloidosis,ischemia,drugs.
  • Lymphatic obstruction:-Whipple1s disease,Lymphangiectasia and Lymphoma.
  • Intestinal lumen:- Bacterial overgrowth and parasites.
  • Endocrinal:-D.M,hypothyroidism,Hyperthyroidism,Adrenal insufficiency and hypoparathyroidism.
  • Cardiovascular diseases:-Due to congestion and hypoxia of intestinal mucosa e.g. in cases of constrictive pericarditis and congestive heart failure.

Clinical Picture:-
a-Manifestations of the cause:-
e.g. Regional enteritis, Whipple's disease, Celiac disease, or
tropical sprue,T.B.
b-General manifestations:-
  • Children:- failure to thrive.
  • Adults:- weight loss,dehydration and low grade fever.
C-Gastrointestinal manifestations:-
  • Steatorrhoea:-bulky, offensive, greasy and glistening stool.
  • Diarrhoea:-due to impaired absorption with increased secretion of water as the unabsorbed bile acids and fatty acids decrease absorption of water and electrolytes.
  • Abdominal pain due to distention or inflammed bowel.
  • Flatus due to bacterial fermentation of unabsorbed carbohydrate.
  • Borborygmi.
C-Manifestations of nutritional deficinecy:-
1-Proteins:-Muscle wasting,osteoporosis and oedema due to hypoproteinemia.
2-Fat:-Loss of S.C fat and visceroptosis.
3-carbohydrate:-hypoglycemia unless the patient is diabetic.
  • vitamin A:-Night blindness,Hyperkeratosis and dermatitis.
  • vitamin D:-Rickets in children and osteomalacia in adults.
  • vitamin K:-Bleeding tendency.
  • vitamin C:-Scurvy.
  • vitamin B1:-Beri Beri.
  • vitamin B2:-Ariboflavinosis,Cheliosis,angular stomatitis and corneal vascularization.
  • vitamin B6:-Peripheral neuropathy.
  • vitamin B12 and folic acid:-Megaloblastic anemia.
  • Niacin:-pellagra.
  • Iron:-Iron deficinecy anemia.
  • Na: Muscle cramps and hypotension.
  • K:Abdominal distension,weakness and arrythmia.
  • Ca and Mg:tetany.
  • Cu:-Dermatitis,depigmentation,anemia.

A-Diagnosis of Malabsorption syndrome:-
1-Quantitative estimation of stool fat:-
If more than 6 gm/24h or more than 15 gm/3days.
2-Carotene in blood:-decreased down to 300mg/dl.

B-To differentiate between malabsorption and maldigestion:-
1-Qualtitative estimation of stool fat:-
  • If non split it is maldigestion.
  • If split it is malabsorption.
2-D-xylose test (absorption secretion test):-
We give 25 gm D-xylose (pentose) orally and 5 hours urinary
excretion of D-xylose is estimated.
- Normally: 5 hours urine should contain > 5 gm and peak
blood level more than 30 mg/dl.
-In malabsorption urinary and blood levels are below normal.

C-Investigation of the cause:-
  • Gastric function tests.
  • Pancreatic function tests.
  • Liver function tests.
  • Stool analysis for bacterial growth and parasites.
  • Jejunal biopsy showing the mucosal appearance.
  • US,CT and MRI
  • Barium follow through:-small intestine is dilated,segmented and loss of the normal feathery appearance of jejunum.
D-Investigation of the complications:-
1-Blood picture:-
- Iron deficiency leads to: Microcytic hypochromic anemia.
- B12 or folic acid deficiency leads to: Macrocytic
normochromic anaemia.
  • Plasma proteins:- is hypoproteinaemia.
  • Serum electrolytes:-Diminished Ca, P, Fe, Na, K, CI & magnesium.
  • Cholesterol:-Diminished.
  • Flat sugar curve.

A-Treatment of the cause:
Surgery for Diverticulosis,strictures or fistulae.
Antituberculous drugs for T.B enteritis.
Flagyl for giardia.
Antibiotics for whipple's disease and tropical sprue.
Antibiotics and surgery for stagnant lobe syndrome.
Gluten free diet for celiac disease.
Low fibers.
Low fat as medium chain triglycerides.
No irritant diet.
C-Parenteral fluids and feeding with supplements of the deficient
elements. Total parentral nutrition can be used.

Dr Ibrahim
Return to list of medical syndromes here

No comments:

Post a Comment

Nice to see your comment here........