[Acne flare-up and deterioration with oral isotretinoin]

Isotretinoin treatment for acne can lead to inflammatory flare-ups or an aggravation, occasionally leading to acne fulminans. The purpose of this work was to examine our cases and to propose a classification system for management.

Over a 3-year period, we selected patients referred to our dermatology unit for paradoxical aggravation of acne under isotretinoin treatment. We recorded clinical data, drug prescriptions and the course of the flare-up.

Over 3 years (1995-1998) we observed 32 cases of acne flare-up in patients taking isotretinoin, 6 women and 26 men.

Four types of aggravation could be identified depending on their date of onset, the skin signs, and the presence or not of general signs. Systemic corticosteroids are generally required, together with a lower daily dose of isotretinoin and local care (excision of open and closed comedons). Factors predictive of aggravation are young age, male sex and sebaceous retention.

Acne fuminans is exceptional in patients taking isotretinoin compared with the number of patients treated. Clinicians should nevertheless be aware of the risk in order to make the diagnosis and provide appropriate care.