Enteropathy, Protein-Losing

Key Features

• Any condition causing excessive loss of serum proteins into GI tract

• Causes include

  • Mucosal disease with ulceration

  • Lymphatic obstruction

  • Idiopathic change in permeability of mucosal capillaries

Clinical Findings

• Hypoalbuminemia

• Lymphocytopenia (< 1000/mcL [1.0 × 10⁹/L]), hypoglobulinemia, hypocholesterolemia in lymphatic obstruction

Diagnosis

• In most cases, protein-losing enteropathy is secondary to a previously established GI disorder

• When etiology of GI protein-loss is uncertain, evaluation should be guided by clinical suspicion

• Exclude nephrotic syndrome, chronic liver disease, heart failure

• Gut α₁-antitrypsin clearance (24-h volume of feces × stool concentration of α₁-antitrypsin/serum α₁-antitrypsin concentration) of > 27 mL/24 h is diagnostic of a protein-losing enteropathy

• Obtain lymphocyte count, serum albumin, protein electrophoresis, cholesterol, antinuclear antibody (ANA), and C3 levels

• Stool samples for ova and parasites

• Small bowel enteroscopy

• CT enteroscopy or wireless capsule endoscopy of small intestine

• Colonoscopy

• CT scan of the abdomen

• Lymphangiography (rarely needed)

• Laparotomy with full-thickness intestinal biopsy

Treatment

• Treat underlying disease

• Low-fat diets supplemented with medium-chain triglycerides for cases caused by lymphatic obstruction

• Octreotide may benefit some patients