A possible pathogenic mechanism for rhabdomyolysis associated with multiple myeloma.

A case of a 44-year-old man in whom kappa light chain multiple myeloma and rhabdomyolysis (RDM) were diagnosed simultaneously is reported. Deposition of the kappa light chain in the cellular membrane of muscle fibers (observed with immunofluorescence techniques and ultrastructural examination) suggests a possible pathogenic mechanism for RDM.