-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).

Causes:-

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.
4-Vitamins:-

• 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.

5-Minerals:-

• Iron:-Iron deficinecy anemia.
• Na: Muscle cramps and hypotension.
• K:Abdominal distension,weakness and arrythmia.
• Ca and Mg:tetany.
• Cu:-Dermatitis,depigmentation,anemia.

Investigations:-

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:-

1-Laboratory:-

• Gastric function tests.
• Pancreatic function tests.
• Liver function tests.
• Stool analysis for bacterial growth and parasites.
• Jejunal biopsy showing the mucosal appearance.

2-Radiological:-

• 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.
2-Chemicals:-

• Plasma proteins:- is hypoproteinaemia.
• Serum electrolytes:-Diminished Ca, P, Fe, Na, K, CI & magnesium.
• Cholesterol:-Diminished.
• Flat sugar curve.

Treatment:-

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.

B-Diet:-

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

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