title: [IgM-lambda type monoclonal gammopathy of undetermined significance showing non-specific anti-streptolysin O activity by a latex immumoaggregation method].
abstract: We report a case of IgM-lambda type monoclonal gammopathy of undetermined significance showing non-specific anti-streptolysin O activity of extremely high level. An 83-year-old man developed high grade fever, cough and sputum. He was admitted to our hospital under a diagnosis of acute pneumonia by chest X-ray. He showed anti-streptolysin O (ASO) activity in extremely high level measured by a latex immunoaggregation method (LA-method). Although antibiotics cured the acute pneumonia, the ASO activity had remained in high level. Serum protein electrophoresis disclosed existence of M-protein and the M-protein was found to be IgM, lambda class by immunoelectrophoresis. The ASO activity measured by the LA method was ascribed to the M-protein because the level of M-component shown by the electrophoresis was decreased by absorption of the serum with streptolysin O-coated latex beads that were used in the LA-method. However, ASO activity measured by Rantzs-Randall method was in normal level. The ASO activity measured by the LA-method was absorbed with bovine serum albumin coated latex beads without streptolysin O. Therefore, it was concluded that the M-protein was not reacted with streptplysin O itself but was reacted with bovine serum albumin coated latex beads. The ASO activity of extremely high level in our case was non-specific reaction caused by the M-protein.
authors.affiliation: Division of Internal Medicine, Mikasa City Hospital.
authors.forename: Y
authors.initials: Y
authors.lastname: Hanai
authors.forename: T
authors.initials: T
authors.lastname: Takahashi
authors.forename: T
authors.initials: T
authors.lastname: Saito
authors.forename: Y
authors.initials: Y
authors.lastname: Kawahito
authors.forename: K
authors.initials: K
authors.lastname: Senga
authors.forename: F
authors.initials: F
authors.lastname: Kondo
authors.forename: M
authors.initials: M
authors.lastname: Isobe
authors.forename: K
authors.initials: K
authors.lastname: Imai
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000989:Antistreptolysin / Q000032:analysis*; D006801:Humans; D007075:Immunoglobulin M / Q000032:analysis*; D007146:Immunoglobulin lambda-Chains / Q000032:analysis*; D007841:Latex Fixation Tests; D008297:Male; D010265:Paraproteinemias / Q000276:immunology*
chemical_list: D007075:Immunoglobulin M; D007146:Immunoglobulin lambda-Chains; D000989:Antistreptolysin