Monitoring of monoclonal gammopathies: rational use of densitometry and rate nephelometry.

The follow-up of patients with monoclonal gammopathies at our institution includes serial serum protein electrophoresis (SPE) with densitometry and IgG, IgA, and IgM quantitative immunoglobulin (QIG) determinations by rate nephelometry. This retrospective audit compares monoclonal protein concentration as estimated by SPE versus QIG in 456 serial serum specimens from 105 patients to determine whether any of the tests provide redundant information. A comparison of the methods demonstrated good correlation between SPE (x-axis) and QIG (y-axis) quantitation for each immunoglobulin class: IgG had a slope of 1.45 and an intercept of 1.60 (Sy/x = 7.46, r = 0.96, n = 250); IgA had a slope of 1.30 and an intercept of -1.37 (Sy/x = 6.85, r = 0.96, n = 78); and IgM had a slope of 1.95 and an intercept of 2.06 (Sy/x = 5.16, r = 0.98, n = 128). The data for individual patients showed similar good correlations. Exceptions included IgA peaks "buried" in the beta region of the SPE (resulting in invalid SPE estimates of monoclonal protein concentration), and IgG peaks of less than 10 g/L (when background polyclonal IgG immunoglobulin skews the QIG estimate of monoclonal protein concentration). An algorithm is proposed whereby monoclonal protein concentration is measured by the specific QIG (i.e., IgG, IgA, or IgM) determination for the routine monitoring of patients, except for those with IgG peaks of less than 10 g/L that are followed by SPE.

Physician reported patient response to immunotherapy: a retrospective study of factors affecting the response.

This study assessed physician evaluation of immunotherapy derived from questionnaires completed at specified intervals during the course of each program in 901 randomly selected patients in the Allergy Clinic, Kingston General Hospital, (1975 to 1985). The objective was to determine safety and efficacy and factors contributing to these from this information. Approximately ninety-six percent of completed questionnaires and 97.5% of patients reported symptomatic improvement. The requirement for supplemental medication was reported in 21.6% of questionnaires and by 35.6% of patients. This requirement was greater in females, in patients with asthma, and in patients with greater numbers of antigens administered. Single antigen programs provided the best response. Systemic reactions were reported in 6.7% of patients treated. In 1% of patients these reactions were severe and required adrenalin for management. Severe reactions occurred when higher concentrations of antigens were injected and frequently developed without warning of prior milder episodes. It was concluded that immunotherapy programs are safe and effective given in appropriate circumstances and with proper safeguards. A monitoring system, however, would provide valuable information on patient progress and collectively may indicate trends in response.