A study of histopathological pattern of neuromuscular disorders with clinico-pathologic correlation

Neuromuscular disorders are frequently seen in our clinical practice, though no certain data are available in this regard. This prospective, observational study which was done as a partial fulfillment of M.Phil (Pathology) degree in BSMMU. The study was undertaken at the Department of Pathology of Bangabandhu Shiekh Mujib Medical University from August 1999 to December 2000 to study the histomorphological pattern of neuromuscular disorders in a selected group of patients attending the neuromedicine, paediatrics and medicine departments of BSMMU. Another purpose of this study was to evaluate the diagnostic utility of muscle biopsy and clinico-pathologic correlation in the diagnosis of neuromuscular disorders. In this study, 55 cases of clinically diagnosed neuromuscular disorders of different kinds were included. Detail clinical history was obtained in all the cases. Clinical diagnosis were made on the basis of history, physical examination, reports of routine and special laboratory tests whenever available. Muscle biopsy was performed in all the cases and histological changes could be identified in 42 cases. In the remaining thirteen undiagnosed cases; eight cases revealed 'essentially normal muscle tissue' and five cases were inadequate for histological evaluation. So, the later two categories were not included for further analysis. Among the histologically diagnosed 42 cases of neuromuscular disorders, basically two different classes of diseases were identified; 1) Dystrophic type of muscular diseases 64.28% and 2) Non dystrophic (acquired) type of neuromuscular diseases such as Inflammatory myopathy 21.82% and Neurogenic muscular atrophy 7.14%. Within the dystrophic group the maximum number of diseases were diagnosed as Duchenne muscular dystrophy 21.49%, Primary myopathy-unclassified 19.04%, Baker muscular dystrophy 4.76% and Limb girdle muscular dystrophy 4.76% etc. Properly executed muscle biopsy is usually the most useful and effective technique for diagnosis of neuromuscular diseases in cases where immunohistochemical, genetic and electron microscopic examination is not possible.