The Iatrogenic Afferent-Loop Syndrome

Abstract

Postgastrectomy physiology requires emptying of food material from the gastric pouch in a forward direction into the distal (efferent) limb of the jejunal anastomosis. Stasis in the proximal jejunal (afferent) loop after distal gastric resection and gastrojejunostomy (Billroth II) may result in intermittent bilious vomiting, malabsorption with steatorrhea, anemia, and weight loss (1–3). This symptom-complex has been termed the afferent-loop syndrome. It is similar to the blind-loop syndrome seen with side-to-side intestinal anastomosis (4). Aspiration from the distended proximal limb yields a high bacterial count, with Gram-negative organisms predominating and resembling colonic flora in both quantity and quality (5, 6). The macrocytic anemia appears related to binding of vitamin B12 by metabolites of Escherichia coli, and treatment with antibiotics frequently gives striking relief (7). Stasis in the proximal loop results from obstruction in either the proximal or the distal jejunal limb close to the gast...