Neuromuscular Disorders: A Histomorphological and Clinicopathological Evaluation in a Tertiary Care Centre

Abstract

Background: Neuromuscular disorders are rare, inherited progressive disorders leading to major disabilities over the years. As a group, there prevalence is not so uncommon and requires attention in view of their rising cases. Muscle biopsy forms an integral part of the diagnostic workup for patients with neuromuscular disorder but is performed in a very few institutes in Asia. In this study, we learn the spectrum of neuromuscular disorders presenting in a tertiary care centre of a developing country, India and evaluate the importance of open muscle biopsy. Material and Methods: 112 Muscle biopsies were reviewed and analysed for investigation of patients with suspected myopathy. Results: Of the 112 cases, 74% of the cases were adults. Mean age of presentation was 25 years and 57% of the cases were males. Pediatric cases constituted 26% of the total cases and 71% of them were male patients. Definitive diagnosis following muscle biopsy was made in 58% (n=65) of cases. Routine histological evaluation revealed the diagnosis of inflammatory myopathy 41% (n=46), muscular dystrophy in 34.8% (n=39),7.1% (n=8) neurogenic, 1.78%(n=2) mitochondrial and 0.8%(n=1) congenital myopathy of the cases. Conclusion: The burden of neuromuscular disorders has increased over the years. Molecular tests are not always helpful in diagnosing LGMD and not accessible to everyone. The role of muscle biopsy is inevitable in detecting false positive cases in mitochondrial myopathy, and for the management of Inflammatory myopathies. Awareness of the utility of muscle biopsy, expertise in diagnosing, and diagnostic challenges need more attention of the clinicians, pathologists and orientation of postgraduates to ease the journey of the patients and their families. Keywords: Muscle biopsy, Enzyme histochemistry, Neuromuscular disorders, Mitochondrial myopathy, Inflammatory myopathy, Morphology