Characterizing organic mood syndrome, manic type.

The purpose of this study is to provide the first empirically based description of the clinical features of organic mood syndrome, manic type (OMS-M). During a recent 5-year period, 14,889 new patients presented for initial evaluation and care at our institute. Of these patients, a total of 12 cases of OMS-M were diagnosed. Evaluations were conducted using the Initial Evaluation Form, which was developed to be compatible with the DSM-III. The symptom profile of OMS-M was compared with that of "functional" manics (bipolar disorder, manic type [BD-M]). A variety of associated clinical factors were also assessed. The OMS-M patient demonstrated somewhat less severe acute symptomatology but more longstanding functional impairment than in BD-M. OMS-M patients also displayed a lower age at onset of illness and a higher level of perinatal problems and developmental delays compared with BD-M patients. The OMS-M group displayed a low family burden of mania. The most striking distinguishing feature of OMS-M was the prevalence of neurological disorders, with a surprisingly high prevalence of seizure disorders. Seizure disorders were more prevalent in OMS-M than in other organic brain syndromes (OBS).