The deoxyuridine suppression test in peripheral lymphocytes

The effects of different deoxyuridine (dU) concentrations on lymphocytes stimulated with phytohemagglutinin (PHA) were studied for use in a lymphocyte dU suppression test (L-dUST). High concentrations of dU were necessary to overcome the unspecific spontaneous pattern of folate deficiency, dU suppression tests with cells of bone marrow (BM-dUST) and with lymphocytes were carried out in 15 patients with vitamin B-12 deficiency, in 12 with folate deficiency, and in 10 with other pathological conditions. L-dUST was also carried out in 15 healthy reference controls. The BM-dUST was able to distinguish patients with vitamin B-12 or folate acid deficiencies from those without, while the L-dUST was unable to do so in most cases. L-dUST does not, therefore, appear to be a reliable method for the diagnosis of megaloblastic changes.

[Evaluation of methods for the detection of syncytial respiratory virus in nasopharyngeal secretions]

The screening for respiratory syncytial virus (RSV) in nasopharyngeal secretions with enzyme immunoassay (ELISA) and indirect immunofluorescence (IIF) has been evaluated in infants and young children with acute respiratory infection. Both methods were compared with viral isolation in HEp-2 cells and the investigation of fluorescent foci in cell cultures inoculated by centrifugation. 226 samples were evaluated by IFF, 182 of which were also evaluated by ELISA while 158 were inoculated into cell cultures. 20.35% of samples were positive with IFF and 19.23% with ELISA. Isolation of RSV was obtained in 25 of the samples inoculated into HEp-2 cells (15.8%). The cytopathic effect took a mean of 5.4 days to develop. The investigation of fluorescent foci in centrifugated cultures allowed to detect 76% of positive samples 24 hours after centrifugation and 84% of positive samples 48 hours after it. Considering the viral isolation as the reference method, IIF and ELISA had a 88% and 76% sensitivity, respectively, with very similar specifities (90.2% and 91.7%).

Shared HLA antigens between parents and recurrent spontaneous abortion

Ten couples with a history of at least three (mean 3.8) consecutive spontaneous abortions of unknown etiology and 57 normal fertile couples (means 2.6 children) were tested for HLA antigens. The frequencies of shared HLA-A, -B and -DR antigens among members of the couples were similar in both groups. Our results, as well as analysis of the data in the literature, contradict HLA antigens sharing between parents as a determinant of recurrent spontaneous abortion.

Generalized Castleman's disease with urinary elimination of heavy chain fragments

A generalized form of Castleman's disease of transitional type is reported in a 66-year-old male who was found in addition to have gamma heavy chain fragments in his urine. One portion of them was constituted by Fc fragments and the other ones by fragments which reacted with anti-Fab/IgG and anti-Fc/IgG antisera but not with anti-kappa and anti-lambda antisera. The findings of the present case support an immunological basis for Castleman's disease.