Protein Losing Enteropathy Information - symptom, cause, picture, treatment of
Protein Losing Enteropathy
Protein Losing Enteropathy Information
Protein-losing enteropathy comprises a number of conditions that result in excessive loss of serum proteins into the gastrointestinal tract. The essential diagnostic features are hypoalbuminemia and an elevated fecal 1-antitrypsin level.
The normal intact gut epithelium prevents the loss of serum proteins. Proteins may be lost through one of three mechanisms:
(1) mucosal disease with ulceration, resulting in the loss of proteins across the disrupted mucosal surface;
(2) lymphatic obstruction, resulting in the loss of protein-rich chylous fluid from mucosal lacteals; and
(3) idiopathic change in permeability of mucosal capillaries and conductance of interstitium, resulting in "weeping" of protein-rich fluid from the mucosal surface.
Hypoalbuminemia is the sine qua non of protein-losing enteropathy. However, a number of other serum proteins such as 1-antitrypsin also are lost from the gut epithelium. In protein-losing enteropathy caused by lymphatic obstruction, loss of lymphatic fluid commonly results in lymphocytopenia (< 1000/L), hypoglobulinemia, and hypocholesterolemia.
In most cases, protein-losing enteropathy is recognized as a sequela of a known gastrointestinal disorder. In patients in whom the cause is unclear, evaluation is indicated and is guided by the clinical suspicion. Protein-losing enteropathy must be distinguished from other causes of hypoalbuminemia, which include liver disease and nephrotic syndrome; and from congestive heart failure. Protein-losing enteropathy is confirmed by determining the gut 1-antitrypsin clearance (24-hour volume of feces x stool concentration of 1-antitrypsin ÷ serum 1-antitrypsin concentration). A clearance of more than 13 mL/24 h is abnormal.
Laboratory evaluation of protein-losing enteropathy includes serum protein electrophoresis, lymphocyte count, and serum cholesterol to look for evidence of lymphatic obstruction. Serum ANA and C3 levels are useful to screen for autoimmune disorders. Stool samples should be examined for ova and parasites. Evidence of malabsorption is evaluated by means of a stool qualitative fecal fat determination. Intestinal imaging is performed with an upper endoscopy with small bowel biopsy and a small bowel barium series. Colonic diseases are excluded with barium enema or colonoscopy. A CT scan of the abdomen is performed to look for evidence of neoplasms or lymphatic obstruction. Rarely, lymphangiography is helpful. In some situations, laparotomy with full-thickness intestinal biopsy is required to establish a diagnosis.
Treatment is directed at the underlying cause. Patients with lymphatic obstruction benefit from low-fat diets supplemented with medium-chain triglycerides. Case reports suggest that octreotide may lead to symptomatic and nutritional improvement in some patients.