Muscular dystrophies and related skeletal muscle disorders in an Indian population--a prospective correlative study

Since most centers in developing countries have limited facilities for investigation of patients with muscular dystrophies and similar disorders, this study was conducted with the aim of assessing the correlation between clinical, electromyographic (EMG) and histopathological findings in this group. We included 100 patients with muscular dystrophy and clinically similar disorders and subjected them to detailed clinical, electrophysiological and histopathological as well as immunohistochemical evaluation. Sensitivity, specificity, positive and negative predictive values and concordance rates for clinical and EMG diagnosis compared to diagnosis after histopathological examination were analyzed. With histopathology as standard, clinical diagnosis and a concordant EMG have very high sensitivity and negative predictive value (100%), but low specificity (33.3%). We conclude that detailed histopathological evaluation with immunohistochemical analysis is essential for the work-up of patients with suspected muscular dystrophies, since occasionally treatable muscle disorders like inflammatory myopathies can be detected when not suspected clinically. Muscle biopsies should only be conducted at major centers where full histochemical facilities are available.