PURPOSE: To evaluate the incidence of transitory monoclonal gammopathies (MG) defined as a narrow spike in serum electrophoresis disappearing after a variable period of time. MATERIAL AND METHODS: A follow up (1986-1992) in all the cases with "minimal" MG (< 10 g/L) to evaluate the transitory or permanent nature of the patients sera was performed along a 7-year period. Serum protein electrophoresis along with immunofixation electrophoresis were performed in order to identify and characterize the monoclonal components in all the cases. RESULTS: Thirty four out of 592 monoclonal gammopathies (5.7% of the total and 8.6% of the non-myelomatous monoclonal components) fulfilled the criteria of transitory monoclonal gammopathies. There was predominance of adult patients (88.2%), females (64.7%) and subjects over 40 years of age (67.6%). The monoclonal component was small in all the cases (mean 4.5 g/L). After immunochemical characterization, IgG was found in 23 cases and IgM in 9; the light chain was Kappa in 25 and lambda in 7; two patients had 2 or 3 monoclonal components. In 31 of the 34 cases the associated pathology was infectious; this being neoplastic in 2 and hypersensitivity to drugs in the remaining patient. The infectious agents could be identified in 24 instances as mainly gram-negative bacteria. CONCLUSIONS: 1) The appearance of a transitory monoclonal gammopathy is not an unusual finding. 2) This alteration does not have any prognostic significance. 3) The appearance of a small monoclonal component, especially in infectious diseases, should not elicit deeper studies.
PURPOSE: To evaluate the incidence of transitory monoclonal gammopathies (MG) defined as a narrow spike in serum electrophoresis disappearing after a variable period of time. MATERIAL AND METHODS: A follow up (1986-1992) in all the cases with "minimal" MG (< 10 g/L) to evaluate the transitory or permanent nature of the patients sera was performed along a 7-year period. Serum protein electrophoresis along with immunofixation electrophoresis were performed in order to identify and characterize the monoclonal components in all the cases. RESULTS: Thirty four out of 592 monoclonal gammopathies (5.7% of the total and 8.6% of the non-myelomatous monoclonal components) fulfilled the criteria of transitory monoclonal gammopathies. There was predominance of adult patients (88.2%), females (64.7%) and subjects over 40 years of age (67.6%). The monoclonal component was small in all the cases (mean 4.5 g/L). After immunochemical characterization, IgG was found in 23 cases and IgM in 9; the light chain was Kappa in 25 and lambda in 7; two patients had 2 or 3 monoclonal components. In 31 of the 34 cases the associated pathology was infectious; this being neoplastic in 2 and hypersensitivity to drugs in the remaining patient. The infectious agents could be identified in 24 instances as mainly gram-negative bacteria. CONCLUSIONS: 1) The appearance of a transitory monoclonal gammopathy is not an unusual finding. 2) This alteration does not have any prognostic significance. 3) The appearance of a small monoclonal component, especially in infectious diseases, should not elicit deeper studies.