Coexistence of central nucleus, cores, and rods: Diagnostic relevance.
BACKGROUND
Congenital myopathies (CMs) though considered distinct disorders, simultaneous occurrence of central nucleus, nemaline rods, and cores in the same biopsy are scarcely reported.


OBJECTIVE
A retrospective reassessment of cases diagnosed as CMs to look for multiple pathologies missed, if any, during the initial diagnosis.


METHODS
Enzyme histochemical, and immunohistochemical-stained slides from 125 cases diagnosed as congenital myopathy were reassessed.


RESULTS
The study revealed 15 cases (12%) of congenital myopathy with more than one morphological feature. Central nucleus with cores (n = 11), central nucleus, nemaline rods and cores (n = 3), and nemaline rods with cores (n = 1). 4/11 cases were diagnosed as centronuclear myopathy (CNM) in the first instance; in addition, cores were revealed on reassessment.


CONCLUSIONS
The prevalence of CMs of all neuromuscular disorders is approximately 6 in 100,000 live births, with regional variations. Three main defined CMs include centro nuclear myopathy (CNM), nemaline rod myopathy (NRM), and central core disease (CCD). However, they are more diverse with overlapping clinical and histopathological features, thus broadening the spectra within each category of congenital myopathy.


CONCLUSIONS
Identification of cases with overlap of pathological features has diagnostic relevance.
Department of Neuropathology, National Institute of Mental Health and Neuroscience (NIMHANS), Bangalore, Karnataka, India.
Sathiyabama
S
Dhinakaran
Department of Neuropathology, National Institute of Mental Health and Neuroscience (NIMHANS), Bangalore, Karnataka, India.
Rashmi Santhosh
RS
Kumar
Department of Neuropathology, National Institute of Mental Health and Neuroscience (NIMHANS), Bangalore, Karnataka, India.
Ravindra
R
Thakkar
Department of Neuropathology, National Institute of Mental Health and Neuroscience (NIMHANS), Bangalore, Karnataka, India.
Gayathri
G
Narayanappa
Congenital myopathies (CMs); cores; nemaline rods