Clinical and serological study of myasthenia gravis using both radioimmunoprecipitation and cell-based assays in a South Asian population.

Background: Identification of autoantibodies has defined distinct clinico-immuno-pathological subtypes of myasthenia gravis (MG) such as AChR-antibody-positive-MG and MuSK-antibody-positive-MG. The use of more sensitive assays such as the cell-based assay (CBA) is expected to reduce the proportion of seronegative-MG. We studied the seroprevalence of AChR and MuSK antibodies using both radioimmunoprecipitation (RIA) and CBA amongst MG patients in Sri Lanka and related their antibody status to their clinical subtypes and severity.