The clinical findings in nine patients with Apert's syndrome (acrocephalosyndactyly) revealed seven postpuberal patients to have widespread moderate-to-severe acne vulgaris on the face, chest, back, and in an unusual manner, the forearms. Since forearm acne is rare, the frequency of this finding without additional evidence of virilization in a group of patients with Apert's syndrome suggested they may have an abnormality of end-organ androgen disposition.
Solomon LM, Fretzin D, Pruzansky S. Pilosebaceous Abnormalities in Apert's Syndrome. Arch Dermatol. 1970;102(4):381-385. doi:10.1001/archderm.1970.04000100029007