Systemic corticosteroid and isotretinoin treatment in cystic acne.

Prednisolone combined with erythromycin was given to 6 patients with cystic acne. The treatment responses were compared to those in 6 patients with cystic acne receiving isotretinoin and erythromycin and also to those in 3 patients with acne fulminans treated with prednisolone and erythromycin. During the first 4 weeks cystic acne showed a clear improvement in 5 out of 6 patients in both treatment groups. A similar improvement occurred in all 3 patients with acne fulminans. When corticosteroid was stopped, 2 out of 5 patients with cystic acne had a relapse and needed isotretinoin for complete control. In the isotretinoin-treated group, one patient with cystic acne needed prednisolone because the acne worsened to an ulcerative form. Slightly elevated liver enzymes, possibly due to erythromycin treatment, were observed in 2 patients with cystic acne and in one patient with acne fulminans. The present results show that prednisolone combined with erythromycin is an effective treatment during the early stages of cystic and febrile acne, but isotretinoin is needed for long-term control.