title: Selective deficiency of C1s associated with a systemic lupus erythematosus-like syndrome. Report of a case.
abstract: We describe a patient who developed a systemic lupus erythematosus-like syndrome characterized by bilateral malar erythema, antinuclear antibody, and anti-double-stranded DNA antibody. He was started on hemodialysis (3 times/week) because of renal failure. He completely lacked total hemolytic complement (CH50) activity, which was subsequently determined to be due to the absence of the first component of complement (C1). The specificity was further defined, by Ouchterlony analysis using anti-C1s antiserum, and was found to be the C1 subcomponent C1s. There was no absence of C1r. We conclude that this is a case of selective deficiency of C1s.
authors.affiliation: Department of Internal Medicine, Toranomon Hospital, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Suzuki
authors.forename: Y
authors.initials: Y
authors.lastname: Ogura
authors.forename: O
authors.initials: O
authors.lastname: Otsubo
authors.forename: K
authors.initials: K
authors.lastname: Akagi
authors.forename: T
authors.initials: T
authors.lastname: Fujita
mesh_terms: D000328:Adult; D003173:Complement C1s / Q000172:deficiency*; D006801:Humans; D005779:Immunodiffusion; D007676:Kidney Failure, Chronic / Q000150:complications; D008180:Lupus Erythematosus, Systemic / Q000150:complications / Q000276:immunology*; D008297:Male; D013577:Syndrome
chemical_list: D003173:Complement C1s