Jejunal diverticulosis. A heterogenous disorder caused by a variety of abnormalities of smooth muscle or myenteric plexus.

We analyzed the clinical, radiographic, esophageal manometric, and pathological features of 10 patients referred with jejunal diverticulosis. Nine patients were over age 59 yr and had symptoms of intestinal pseudoobstruction of 5-43 yr duration. Seven had surgery for mechanical obstruction, although none was found. Eight had diarrhea, steatorrhea, and weight loss. Five had Raynaud's phenomenon and heartburn, and 2 had dysphagia. At radiography, 9 had jejunal diverticula with or without duodenal or ileal diverticula, or both. Two each had abnormal structure or motility of the esophagus or stomach. At manometry, 3 of 7 had a nonspecific motor abnormality, and 1 other had low amplitude peristaltic waves. Light microscopy of small intestinal tissue in 7 patients showed that 4 had fibrosis and decreased numbers of normal-appearing muscle cells, findings consistent with progressive systemic sclerosis. Two others had fibrosis associated with degenerated smooth muscle cells, findings consistent with a visceral myopathy. The seventh patient had neuronal and axonal degeneration and neuronal intranuclear inclusions, findings consistent with a visceral neuropathy. We conclude that (a) intestinal pseudoobstruction is a major clinical manifestation of jejunal diverticulosis, (b) jejunal diverticulosis is a heterogenous disorder associated with at least three abnormalities of the smooth muscle or myenteric plexus, (c) in contrast to intestinal pseudoobstruction without diverticulosis, the esophagus, stomach, and colon are less frequently involved in jejunal diverticulosis, and (d) some patients with jejunal diverticulosis probably have clinically inapparent progressive systemic sclerosis.