Rheumatic masks of plasma cell dyscrasias

Objective: to consider clinical practice problems in the differential diagnosis of different types of plasma cell dyscrasias (PCD). Subjects and methods. Fourteen patients (8 men and 6 women) aged 52±12 years, in whom rheumatic diseases (RD) were ruled out and who were diagnosed as having primary PCD: different types of myeloma in 7 patients, myeloma + AL-amyloidosis in 2, AL-amyloidosis in 3, and Waldenstrom’s macroglobulinemia in 2, were examined. Results and discussion. The most common maldiagnosed RDs in patients with PCD were seronegative rheumatoid arthritis (RA), systemic lupus erythematosus, Sjogren’s disease, and different forms of vasculitis. The most frequent masks of RD were kidney (78%) and osteoarticular system (64%) lesions, vascular disorders (36%), peripheral polyneuropathies (36%), and enlarged salivary glands with xerostomia (28.5%). Serum and urine immunochemical study should be performed in all patients who have clinical manifestations of seropositive RA, spondyloarthritis, intensive bone pain syndrome, ulceronecrotic vasculitis, enlarged submandibular salivary glands with macroglossia in the absence of markers of autoimmune disease for the timely diagnosis of PCD and the exclusion of RD. The paper estimates the sensitivity and specificity of main methods used to diagnose different types of PCD.