Sudulagunta et al listed 2 criteria for making the diagnosis of myasthenia gravis (MG). The authors are from Columbia Asia Hospital, Baptist Hospital, K.S. Hegde Medical College and Dr B.R. Ambedkar Medical College in Bangalore, India.
Criteria 1 - Both of the following
(1) presence of antibodies to acetylcholine receptor (AChR) or muscle specific kinase (MuSK)
(2) one or both of the following:
(2a) positive decremental response on repetitive nerve stimulation testing at 3 Hz
(2b) clinical exam consistent with MG
Criteria 2 - All 3 of the following:
(1) positive decremental response on repetitive nerve stimulation testing at 3 Hz
(2) clinical exam consistent with MG
(3) exclusion of other conditions causing similar clinical features (muscle weakness, fatigue)
Distribution of antibodies:
(1) antibodies to acethylcholine receptor (AChr): up to 90%
(2) antibodies to MuSK: up to 5%
(3) other ("double seronegative"): up to 10%
