Significance of Immunohistochemical Study in Patients with Muscular Dystrophy

ABSTRACT

BACKGROUND: For the differential diagnosis between the various subtypes of muscular dystrophy, the analysis of the protein expression pattern from the biopsied skeletal muscle tissue is essential. Authors performed the immunohistochemical study (IHC) using sets of antibodies for the differentiation of subtypes of muscular dystrophy. METHODS: Antibodies against dystrophin C-terminal, dystrophin rod domain, dystrophin N-terminal, alpha-, beta-, gamma-sarcoglycans, laminin alpha2 chain, dysferlin, and beta-dystroglycan were used for the IHC study in 43 patients with muscular dystrophy. The reactivity against the specific antibodies was graded and the clinical findings were assessed. RESULTS: We found 15 cases of dystrophin deficiency and 7 cases of dysferlin deficiency. Those with dystrophin deficiency were clinically classified previously as follows, 11 cases with Duchenne's muscular dystrophy (DMD), two with congenital muscular dystrophy (CMD), one with Becker's muscular dystrophy (BMD), and a female patient with limb-girdle muscular dystrophy (LGMD). Those with dysferlin deficiency consisted of 4 cases with LGMD phenotype and 3 with distal myopathy. CONCLUSIONS: The results of our study confirm the dystrophin immunostain is essential for the identification of dystrophinopathies among the various subtypes of muscular dystrophy. Also, the identification of 7 cases with dysferlin deficiency suggests dysferlinopathy is the common cause of muscular dystrophy in Korea.