Free fragments of gamma chain in the urine. A possible source of confusion with gamma heavy-chain disease.

With currently used microconcentrators, high-resolution electrophoresis, and immunofixation electrophoresis, relatively homogeneous free fragments of gamma chain (FFGC) unaccompanied by light chains, which cannot be found in the serum, may be discovered in the alpha-2 region during routine examination of the urine. The urinary alpha-migrating FFGC is of no apparent clinical significance and should not be confused with the antigenically related FFGCs of gamma heavy-chain disease. In gamma heavy-chain disease, the FFGCs are often demonstrable in the urine, but are always present in the serum and migrate in the beta-gamma region.

Chorioangiomas of intermediate size and intrauterine growth retardation.

Very large chorioangiomas are a rare but well recognized cause of neonatal morbidity, while small ones are clinically insignificant. This study emphasizes that some chorioangiomas of intermediate size may be causally related to intrauterine growth retardation, and that they may be surprisingly difficult to detect in the unfixed placenta.

Vulvovaginal polyps. Histologic appearance, ultrastructure, immunocytochemical characteristics, and clinicopathologic correlations.

A clinicopathologic study of 18 vulvovaginal fibroepithelial polyps with a comparison to normal stroma is presented. Twelve cases were analyzed by immunohistochemical methods for the presence of vimentin, desmin, muscle-specific actin, myoglobin, S-100 protein, alpha 1-antitrypsin (AAT), alpha 1-antichymotrypsin (ACHT), cytokeratin (AE1/AE3), and epithelial membrane antigen. Stromal cells reacted with vimentin antiserum in eight cases. Desmin reactivity was detected in five of 12 cases, four of which coexpressed vimentin. Two cases exhibited muscle-specific actin reactivity, and a single case weak AAT reactivity. The stromal cells were unreactive with S-100 protein, epithelial membrane antigen, cytokeratin, ACHT, and myoglobin. Ultrastructurally, the stromal cells of four fibroepithelial polyps resembled fibroblasts and myofibroblasts. Our immunohistochemical and ultrastructural data suggest that the stromal cells of fibroepithelial polyps are a collection of functional fibroblasts that may be capable of differentiating along two or more cell lines. Dramatically elongated cytoplasmic processes extend from both normal vulvovaginal stromal cells and the cells of the polyps. The cell attachments to each other and to bundles of collagen suggest a potential for a physiologic role in tissue contractility, especially in the immediate postpartum state. The common association with pregnancy may represent a local exuberant response to some presently unidentified trophic or stimulating factor.