Sporadic Late-onset Nemaline Myopathy Associated with Multiple Myeloma.

Sporadic late-onset nemaline myopathy (SLONM) is a rare, acquired myopathy that is frequently associated with monoclonal gammopathy, most commonly monoclonal gammopathy of undetermined significance (MGUS). However, its association with overt multiple myeloma (MM) has been rarely reported. We present a case of SLONM associated with MM in which chemotherapy targeting the underlying MM led to mild-to-moderate improvement in muscle symptoms. This case underscores the potential pathogenic role of MM in SLONM and highlights the importance of treating underlying hematologic malignancies.