[Vitamin D deficiency. Osteopathy after prolonged treatment with anticonvulsents (author's transl)].

Several substances with anticonvulsent activity can lead to hypovitamenosis D after prolonged use through their effect on vitamen D metabolism in the liver. This results in abnormal bone mineralisation and produces rickets or osteomalacia. Radiological examination of the skeleton should be performed on patients receiving prolonged anticonvulsent therapy, in order to arrive at an early diagnosis. This requires an accurate knowledge of the types of bone abnormality and of their most frequent localisation. Pathological findings such as Looser's zones, epiphyseolysis or delayed development must be considered in this context. Radiological examination provides an accurate diagnosis if combined with clinical findings and important biochemical results: reduced calcium and raised alkaline phosphatase. Treatment with vitamen D must then be instituted. Healing may be complete or leave residual changes, depending on the severity of the bone changes.