Myasthenia gravis and acetylcholine receptor antibodies: A clinico immunological correlative study on South Indian patients

Acquired myasthenia Gravis (MG), a disorder of impaired neuromuscular transmission is recognized as an autoimmune disorder, with a majority of the patients having antibodies against acetylcholine receptor (AChR antibodies) in the serum. AIM AND OBJECTIVES: To correlate the AChR antibody status with the clinical characteristics of patients with myasthenia gravis. STUDY DESIGN: Retrospective and prospective study. MATERIALS AND METHODS: This study was carried out in patients with definite MG, attending the Neurology services of the National Institute of Mental Health and Neurosciences, Bangalore, India, during the period 1999-2003. The AChR antibody status was determined using the direct and indirect enzyme linked immunosorbent assay (ELISA) technique. RESULTS: There were 165 patients in this study (M : F :: 1.5 : 1). The overall seropositivity rate was 59.4%. Seropositive patients had higher age of onset and presentation, and more frequent occurrence of crises, both at presentation and at any time during the course. Other parameters, viz. gender of the patient, Osserman staging, thymic enlargement on CT and remission during follow-up did not differ between the two groups. CONCLUSION: This communication reports the result of AChR antibody assay in a large cohort of patients, using a simple diagnostic tool, namely direct and indirect ELISA technique. In addition, the characteristics of a large cohort of patients with seronegative myasthenia gravis are described.