Systemic lambda light-chain deposition in a patient with myeloma

Systemic lambda light-chain deposition occurred in a 73-year-old man with myeloma. An initial renal biopsy specimen showed the features of myeloma kidney. When he died 22 months later lambda light chains were detected by immunofluorescence in kidneys, liver, spleen, and heart. They were probably responsible for cardiac dysfunction and the fatal arrhythmia. It is suggested that in this patient deposition was due to a structural alteration of the light chains, possibly induced by cyclophosphamide.