Nodulo-cystic eruption with musculoskeletal pain

A healthy 17-year-old white patient with mild acne was treated with isotretinoin (Accutane), 40 mg/day. After a month of treatment, the acne got worse and the patient complained of polymyalgia and arthralgia.

An examination revealed numerous nodules and cysts covered by hemorrhagic crusts on his chest and back (FIGURE). The patient had severe muscular tenderness with gait disability. Leukocytosis and elevated erythrocyte sedimentation rate (ESR) were found; creatinine phosphokinase was within the normal values.

FIGURE
Nodules and cysts on chest and back

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