Concomitant manifestation of systemic lupus erythematosus and low-grade non-Hodgkin’s lymphoma

We describe a patient presenting with systemic lupus erythematosus (SLE) and concomitant low-grade (lg) non-Hodgkin’s lymphoma of the B cell type (B-NHL). Although the association of autoimmune disorder and lymphoma is well conceived, there is only scarce information available as to the simultaneous occurrence of both disease conditions in one patient. As in this patient diagnosis of lg B-NHL was also based on the detection of a monoclonal population of CD5+ B lymphocytes, and given that the polyclonal expansion of CD5+ B cells has been previously reported in rheumatoid arthritis (RA), Sjögren’s syndrome (SS) and single cases of SLE, the observations we made in this patient led us to discuss the role of the CD5+ population in the development of rheumatic disorders and concomitant lymphoid malignancy. Moreover, since impaired production rates of interleukin 3 (IL-3) and interleukin 4 (IL-4) have been associated with an abnormal expansion of CD5+ lymphoma cells and seeing that soluble interleukin 2 receptor (sIL-2R) serum levels were found to be positively correlated with disease activity both in SLE and lg B-NHL, these parameters were investigated and related to the patient’s disease state throughout the entire clinical observation period.