[Primary amyloidosis associated with kappa light chain myeloma]

The clinical spectrum of plasma cell dyscrasias includes primary amyloidosis and multiple myeloma. These two entities are present at the time of diagnosis in 10 percent of cases.

A 72 years old female was admitted to our Institution with oligoanuric renal failure. Renal ultrasonography revealed normal kidney dimensions, with a slight decrease in the normal parenchyma-sinus differentiation. The complementary study identified free kappa light chains in urine (73,9 mg/dL) and bone marrow study fulfilled the criteria for multiple myeloma. Search for amyloid fibrils in abdominal subcutaneous fat was positive. The serum beta-2 microglobulin level was elevated (26 mg/L). Transthoracic echocardiogram did not reveal pathologic findings. Treatment initiation was complicated by hemodialysis catheter-associated Staphylococcus aureus infection.

Primary amyloidosis associated with light chain myeloma is a rare, and often late, diagnosis with a dismal prognosis. Renal failure is a frequent initial presentation of the disease and infection an important cause of death.