Resolution of pure red cell aplasia and lymphoma: response to intravenous gammaglobulin and combination chemotherapy.

Pure red cell aplasia (PRCA) rarely occurs in nonthymic lymphoproliferative disorders. This report describes the clinical course and therapy of a patient with a history of Sjogren syndrome who developed well-differentiated lymphocytic lymphoma associated with PRCA and severe hemolytic anemia. Life-threatening hemolytic anemia combined with the presence of multiple antibodies and lack of erythroid precursors was treated successfully with a single dose of intravenous gammaglobulin. A sustained, complete remission and normalization of the bone marrow was achieved following six courses of an aggressive chemotherapy regimen. Thus, occasionally low-grade lymphomas can produce life-threatening complications, requiring a more aggressive therapeutic intervention than those routinely applied.

Screening to detect asymptomatic shedding of herpes simplex virus (HSV) in women with recurrent genital HSV infection.

To investigate the asymptomatic shedding of herpes simplex virus (HSV) from women with recurrent genital herpes infection, and to assess whether inapparent shedding could occur, eight such women were examined thrice weekly for one month. At each visit colposcopy was performed and multiple sites sampled for HSV. During the study four women had no recurrence of HSV infection, but four had at least one positive viral culture. One of these patients was asymptomatically shedding HSV on nine of her 11 clinic visits. Two episodes of urethral shedding were detected. In this group of patients the presence of inguinal lymphadenopathy was appreciably associated with the isolation of HSV from the urogenital tract.

Structure-activity relationships of putative primaquine metabolites causing methemoglobin formation in canine hemolysates.

A rapid and reproducible in vitro test system was developed to measure the methemoglobin (MHb)-forming properties of various 8-aminoquinoline derivatives. Initial rates and extents of reaction were measured spectrophotometrically with either canine hemolysates from which ferrihemoglobin reductase was removed, or with purified human oxyhemoglobin (Hb). The results demonstrate that primaquine derivatives that can be oxidized to quinones or iminoquinones (5-hydroxy,6-desmethyl primaquine; 5-hydroxyprimaquine; 5,6-dihydroxy-8-aminoquinoline; and 5-hydroxy, 6-methoxy-8-aminoquinoline) are potent MHb-forming compounds. Studies on the extent of reaction in hemolysates and purified oxyhemoglobin suggest that the extent of MHb formation may be limited by the rate at which the corresponding iminoquinones or quinones arylate nucleophiles. The effects of glutathione, mannitol, ascorbate, and superoxide dismutase on the rate and extent of hemoglobin oxidation by 5,6-dihydroxy-8-aminoquinoline suggest that these compounds oxidize Hb similar to the mechanism known for dimethylaminophenol (DMAP), in which Hb oxidizes the quinoline to semiquinone radical and quinone species which are the oxidizing and arylating agents.