Synonyms:
a.k.a. Adult from of nemalin myopathy a.k.a. acquired nemaline myopathy, rare:
Clinical features:
Adults a.k.a. late onset nemaline myopathy: usually >40 year olds, head drop, proximal >distal weakness, dysphagia, respiratory weakness, proximal and axial atrophy
Associated conditions:
- SPEP: monoclonal gammopathy.
- HIV associated nemaline myopathy.
Muscle biopsy:
HE fibre atrophy without grouping, subsarcolemmal increased eosinophilic staining. GMT subsarcolemmal purple/red nemaline rods in type 1 fibres. Often type 1 fibre hypertrophy, type 1 fibre predominance.
EM: nemaline rods= osmiophilic rods
Immunohistochemistry: Alpha actinin type 2 positive rods in a lot of cases, myotilin positive rods
Note: nemaline rods can occur in inflammatory muscle disease and in central core disease and nemaline myopathy (a form of congenital myopathy).
Findings on investigations:
NCS/EMG: Myopathic, fibrillation
CK: normal
Also see nemaline myopathy (a form of congenital myopathy)
Treatment:
Consider:
- Stem cell transplantation. [case reports]