Differential hepatotoxicity of two oral retinoids (etretinate and isotretinoin) in a patient with palmoplantar psoriasis.

A 64-year-old woman developed biopsy-proven hepatitis during oral treatment of severe pustular psoriasis of palms and soles with an aromatic retinoid, etretinate. The elevations in hepatic enzyme levels reappeared when etretinate was reinstituted 18 months later. Analysis of serum and subcutis showed normal therapeutic concentrations of the drug. Isotretinoin therapy, although apparently devoid of hepatotoxicity, was clinically only marginally effective. Evidence compiled from the literature suggests that etretinate-hepatitis is a drug-specific reaction.