Late-onset myopathy responsive to immunomodulatory treatment: sporadic late-onset nemaline myopathy without nemaline rods?

We propose that the diagnosis of SLONM should be considered even in the absence of nemaline rods in muscle biopsy, and this should not impede the consideration of immunomodulatory treatment. Future progress in understanding the pathogenetic basis of SLONM may reduce reliance on pathological findings in muscle biopsies for establishing the diagnosis.