Radiographic bone surveys after isotretinoin therapy for cystic acne

Seven patients underwent retrospective radiographic examination 10 to 16 months after high dose isotretinoin therapy for severe cystic acne. One patient, who received the highest isotretinoin dose (approximately twice the average dose taken by the remaining patients), had multiple small hyperostoses of the thoracic spine and tarsi navicular. These findings were identical to the skeletal changes known to occur during retinoid administration. Prospective studies are needed to ascertain the risk of developing hyperostoses during isotretinoin therapy for acne at the lower doses currently employed. In this preliminary study, clinically significant hyperostoses were not a late sequela of high dose isotretinoin treatment for acne.