Paraneoplastic visceral neuropathy as a cause of severe gastrointestinal motor dysfunction.

The purpose of this study was to define the cause of severe gastrointestinal motor dysfunction in 7 patients with lung cancer. Six patients had small cell carcinoma and 1 patient had pulmonary carcinoid. Their ages ranged from 58 to 74 yr. All had intestinal pseudoobstruction and obstipation/constipation; 6 of 7 patients had gastroparesis; 4 of 4 patients had esophageal peristaltic abnormalities; and 2 patients had neurogenic bladders, autonomic insufficiency, and peripheral neuropathy. Five of 7 patients had dilated small bowel with 4 of them showing slow transit of barium; 2 of 7 patients had dilated colons; and 3 of 7 patients had slow colonic transit. Five patients died 4-9 mo after onset of gastrointestinal symptoms, and 2 survived. Post-mortem or surgical samples of the esophagus, stomach, small bowel, and colon showed neuron and axon degeneration and dropout, lymphoplasmacytic infiltration, and glial cell proliferation within the myenteric plexus of 6 patients. The antrum from the seventh patient had inflammatory cells within the myenteric plexus but without neuron dropout. Neuron numbers were significantly less than normal in each area of the gastrointestinal tract. Thus, we conclude that lung cancer may be complicated by severe gastrointestinal motor dysfunction resulting from visceral neuropathy of the myenteric plexus, a paraneoplastic effect of the cancer.

Reticulate bodies as single antigen in Chlamydia trachomatis serology with microimmunofluorescence.

Formalin-fixed, purified reticulate bodies (RB) of Chlamydia trachomatis immunotype C/TW-3/OT were used as a serological test antigen in the microimmunofluorescence test. The sensitivity and specificity of the RB antigen were compared to elementary bodies (EB) used as antigens in the detection of C. trachomatis antibodies in human sera by microimmunofluorescence. RB reacted with all known C. trachomatis immunotypes with the same sensitivity as the homotypic EB. In routine serology with sera and endocervical secretions, the RB antigen had a sensitivity similar to that of the EB in detecting serum antibodies, endocervical secretion antibodies, and antibodies of immunoglobulin M and G classes. No false-positive reactions were detected with control sera. All positive reactions showed type-specific antibodies against an EB immunotype. RB seemed to demonstrate chlamydial group reactivity; sera from 10 psittacosis patients diagnosed clinically and serologically by complement fixation showed five positive, three equivocal, and two negative reactions. By immunofluorescence, RB appeared as distinct rings demonstrating uniform peripheral surface fluorescence at their rims. The EB appeared as pinpoint-sized dots. C/TW-3/OT RB used as a single test anitgen should provide a simple and sensitive serological assay for the detection of C. trachomatis antibody.