Clinical, histological and radiological responses to methylprednisolone in HIV-associated rod myopathy

- HIV patients with proximal weakness must be evaluated for sporadic late-onset nemaline myopathy.
- MRI is helpful in identifying inflammatory process in HIV-associated rod myopathy.
- Rod myopathy in HIV patients might be caused by an immune dysregulation.

Skeletal muscle involvement as a neurologic manifestation in individuals with HIV is rare, especially as rod myopathy. We describe a 41-year-old male with HIV infection who presented progressive proximal muscle weakness and limb-girdle atrophy. A muscle magnetic resonance image showed bilateral fatty infiltration and post-contrast enhancement in the arm and thigh muscles. The muscle biopsy revealed intracytoplasmic aggregates with appearance of nemaline rod bodies with Gomori trichrome staining and electron microscopy in most fibers. The patient underwent six cycles of intravenous methylprednisolone pulses, presenting clinical improvement. Post-treatment muscle biopsy showed fewer nemaline bodies and muscle magnetic resonance image depicted a pronounced reduction of muscular edema. These findings corroborate that deposition of nemaline bodies in these patients might be related to an immune response triggered by the virus.