Cryoglobulin crystal arthropathy in a patient with multiple myeloma.

Joint involvement is unusual in patients with monoclonal gammopathies. It has been characteristically described as a rheumatoid-like seronegative polyarticular erosive arthropathy, which also has been related to crystal deposition of cryoglobulins in the synovium and several other tissues. This report describes the case of a 57-year-old African American woman with a seronegative polyarthritis associated with deposition of nonbirefringent or weakly positive birefringent rhomboid-shaped crystals in the synovial fluid.

Viral rhabdomyolysis.

Virus-induced myopathy can be an important cause of life-threatening rhabdomyolysis. We report the case of a 30-year-old patient who developed rhabdomyolysis and acute renal failure in association with herpes simplex virus infection.