SARCOIDOSIS AND MYELOMA OF LAMBDA‐TYPE IgG

. This report is concerned with the combination of chronic sarcoidosis and myeloma. The myeloma, of lambda-type IgG, was diagnosed 6 years after the onset of sarcoidosis. A gradually increasing ESR during the interval provided an indication of gradual development of the plasma cell dyscrasy. Signs were observed of depressed cellular immunity, most probably attributable to the sarcoid disease. Phytohaemagglutinin-induced lymphocyte transformation in vitro was markedly depressed. In comparison with earlier test results the tuberculin skin reaction was depressed. The in vitro response, with PPD as stimulant, was compatible with the skin reaction. Lymphopenia was present, but the ratio of T and B lymphocytes was normal. A discussion bears upon the discrepancy between the poor PHA response and the normal number of T lymphocytes, and the possible relationship between sarcoidosis and myeloma, as compared with known disorders associated with monoclonal paraproteinaemia.