Factors of error involved in the diagnosis of juvenile myoclonic epilepsy: A study from South India.

The study was aimed at finding possible factors for delay in the diagnosis of juvenile myoclonic epilepsy (JME) in a developing country. Data was analyzed retrospectively through the medical records and prospectively through a re-evaluation of the history and EEGs of patients with JME registered in a university hospital in south India. Of the 131 patients, 23 (17.5%) patients were seen by neurologists before registration in the clinic. Diagnosis of JME was established in 118 patients at the time of registration and in 13 (10%) patients during follow-up in the clinic. The mean interval between onset of disease and the diagnosis was 6.8 + 6.3 years. In 20 patients the diagnosis was established 10 years after the onset. The mean interval between the first evaluation and diagnosis was 24. 2 months in the 13 patients in whom the diagnosis was established during follow-up in the clinic. Lack of familiarity with the clinical syndrome was probably the factor for delay in the diagnosis in 108 patients seen by practising physicians. The factors for delay in the diagnosis in patients seen by neurologists included failure to ask about myoclonic jerks resulting in misinterpretation of EEGs in 28 patients, misinterpretation of absences and/or unilateral jerks in 4 patients, and failure to ask about myoclonic jerks and misinterpretation of focal EEG abnormalities in 4 patients. This study suggests that the possible factors of error in the diagnosis of JME among the neurologists were similar to the observations reported from the developed countries; whereas the factor for delay in the diagnosis of JME among practising physicians was lack of familiarity with the epileptic syndrome.