NEUROPHYSIOLOGIC CORRELATES OF ORGANIC ACIDEMIAS - A SURVEY OF 107 PATIENTS

The files of 107 patients with 19 different types of organic acidemia were reviewed retrospectively. Approximately 50% of the patients had a bnormal electroencephalogram (EEG) at the time of initial study. In pa tients who had serial studies, the EEG deteriorated in 38% and improve d in 15%. The predominant EEG abnormality encountered was slowing of t he background activity in various degrees. Focal or generalized paroxy smal activity occurring in conjunction with slow background activity i ndicated a poor prognosis. Brainstem auditory evoked potentials (BAEP) , visual evoked potentials (VEP), and somatosensory evoked potentials (SEP) were analyzed. The VEP was abnormal in 44%, BAEP in 39%, and SEP in 29% of the patients. Given the magnitude and frequency by which ne urophysiological abnormalities occur in organic acidemias, neurophysio logy testing provides complementary functional information and has an important place in the clinical work-up of these diseases.