Flow cytometric immunophenotyping and comparison with immunocytochemistry in small round cell tumors.

OBJECTIVE: To quantitate different antigens by flow cytometric immunophenotyping (FCI) in small round cell tumors (SRCTs) and to compare the FCI technique with immunocytochemistry (IC). STUDY DESIGN: IC and FCI were performed on 24 consecutive cases of SRCT on fine needle aspiration biopsy material using a panel of antibodies--e.g., cytokeratin (CK), leukocyte common antigen (LCA), desmin, epithelial membrane antigen, neuron-specific enolase, chromogranin, retinoblastoma gene product, neuroblastoma clone (NB84a (NB), vimentin and Mic-2 gene product. IC was done by indirect immunoperoxidase and FCI by indirect immunofluorescence onflow cytometry. RESULTS: In Ewing's sarcoma, with the help of FCI, positive results were obtained in an additional 4 samples in CK, 2 samples in actin and 3 samples in desmin. Similarly, one each sample was additional positive regarding Mic-2 and vimentin by IC. In cases of neuroblastoma with the help of FCI, additional positive results were obtained in one each sample of CK, LCA and NB and two in actin. Combined use of FCI and IC helped to show chromogranin positivity in an additional two cases. Divergent differentiation was noted in four cases of Ewing's sarcoma, one neuroblastoma and two peripheral neuroectodermal tumors. CONCLUSION: FCI technique is sensitive, more objective and quantitative in comparison with manual absorbance-based microscopic detection of enzyme immunohistochemistry products. FCI may determine divergent differentiation in SRCTs.     

Acute phase reactants in leprosy.

Serum levels of C-reactive protein (CRP) and plasma levels of fibronectin (Fn) were studied in 74 untreated leprosy patients. CRP was detected by latex agglutination in 25.6% of the patients. A significant increase in Fn levels was seen in all the groups of leprosy patients, as compared to the controls.     

Use of Polytomous Logistic Model in Matched Case-Control Studies

Binary logistic model has been found useful for estimating odds ratio in case of dichotomous exposure variable under matched case-control retrospective design. We describe the use of polytomous logistic model for estimating odds ratios when the exposure of prime interests, relative to disease incidence, has more than two levels. An illustrative example is presented and discussed.     

Anti-trichomonal IgA antibodies in trichomoniasis before and after treatment

Anti-trichomonal IgA antibodies were estimated by enzyme-linked immunosorbent assay (ELISA) in serum and vaginal secretions of 25 symptomatic and 25 asymptomaticTrichomonas vaginalis positive patients before and after treatment and in 25 age-matched controls. Significantly higher levels of antitrichomonad IgA antibodies were found inT. vaginalis positive patients when compared to control subjects, especially in vaginal secretions. In addition, a significant decrease in these antibodies was observed after treatment, which was more pronounced in vaginal secretions. It seems that anti-trichomonal IgA antibodies in serum and more so in vaginal secretions are directly related to and specific to the presence ofT. vaginalis in the urogenital tract.