[Convulsions in the fifth day of life. A critical study].

BACKGROUND: Cases of fifth day fits, first described in 1977, remain rare. Their cause is not known and each report contributes to knowledge of the phenomenon.

PATIENTS AND METHODS: Sixteen infants born between December 1971 and January 1992 were selected because they were admitted to our department for convulsions satisfying the criteria for fifth day fits. Their files were carefully analysed, with special attention paid to pregnancy, delivery, clinical status after birth, EEG during the crisis and some laboratory data. Follow-up was also considered.

RESULTS: The frequency of these fits remained stable until 1985; only 2 cases have been seen since then. There was no seasonal variation. The characteristic EEG pattern was seen in only 10 patients. All the laboratory data were negative. Follow-up with sufficient duration (1 to 12 years) provided only 8 cases satisfying all the classical criteria. The convulsions of one patient could be attributed to perinatal anoxia, 2 other patients developed epilepsy, and possible perinatal causes could have been neglected in 2 cases.

CONCLUSION: This study provides no new information on the cause of fifth day fits. Disturbances of brain maturation might be responsible.