CONGENITAL MYOTONIA, EPILEPSY and SCHIZOPHRENIA: AN UNUSUAL ASSOCIATION

We report on a 24-year-old adopted man, that since he was 8mounth-old, presented with inability to release a grasp. At 1 year of age he complained of epileptic seizures, successfully treated with phénobarbital and carbamazepine. At 15 years of age, because of his psychotic disturbances, he had a diagnosis of schizophrenia. When clinically examined, he showed a diffuse muscular hypertrophy with characteristic myotonic features al the hands. Intellectual evalutation revealed impaired cognitive functions. Cerebral SPECT with 99mTc-HMPAO evidenced a reduced perfusion at basal ganglia. Serum CK level was mildly increased. CNEMG was positive for myotonic discharges. Muscle biopsy revealed some atrophie fibers and an increased number of internal nuclei. Recent molecular studies have demonstrated a relationship between alterations of ionic channels (channellopathies) in muscle diseases as myotonic syndromes, diskaliemic paralyses, etc. A pathogenic role of these alterations has also been postulated in some forms of epilepsy and schizophrenia. In the light of these recent observations, we hypothesize that the three diseases affecting our patient may represent an unusual association, possibly dependent on a common pathogenic mechanism.