title: [A case of selective IgM deficiency associated with systemic lupus erythematosus].
abstract: We report a case of selective IgM deficiency associated with systemic lupus erythematosus (SLE). A 34-year-old female suffering from SLE was admitted with proteinuria and general fatigue. Laboratory findings revealed a very low serum IgM level, almost lower than 12 mg/dl. Renal biopsy findings showed diffuse proliferative lupus nephritis (DPLN). In immunofluorescent microscopy, IgG was the most strongly stained followed by IgA, but IgM staining was only faint. As for the immunophenotype of the T cells, the OKT4/OKT8 ratio was normal. Response to both phytohemagglutinin (PHA) and concanavalin A (ConA) was normal. However, responses of B cells to both pokeweed mitogen (PWM) and Staphylococcus aureus Cowan strain I (SAC) were significantly reduced. Surface IgM-positive B cells were decreased. These results indicate that the patient had B cell dysfunction, involving impairment of B cell differentiation. In this report, we discuss selective IgM deficiency and SLE documented in the literature.
authors.affiliation: Department of Nephrology, Saiseikai Nakatsu Hospital, Osaka, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Tanaka
authors.forename: M
authors.initials: M
authors.lastname: Kasahara
authors.forename: T
authors.initials: T
authors.lastname: Miyawaki
authors.forename: K
authors.initials: K
authors.lastname: Yahata
authors.forename: H
authors.initials: H
authors.lastname: Hashimoto
authors.forename: A
authors.initials: A
authors.lastname: Sugawara
authors.forename: S
authors.initials: S
authors.lastname: Ueda
authors.forename: T
authors.initials: T
authors.lastname: Matsuo
authors.forename: T
authors.initials: T
authors.lastname: Kuwahara
mesh_terms: D000328:Adult; D001402:B-Lymphocytes / Q000276:immunology; D004406:Dysgammaglobulinemia / Q000150:complications*; D005260:Female; D006801:Humans; D007075:Immunoglobulin M / Q000172:deficiency*; D007668:Kidney / Q000473:pathology; D008180:Lupus Erythematosus, Systemic / Q000209:etiology* / Q000473:pathology
chemical_list: D007075:Immunoglobulin M