A 26-year-old man started high-dose prednisolone 3 weeks ago for nephrotic syndrome. He now has numerous uniform small erythematous papules and pustules over the chest, upper back and shoulders. There are no comedones, cysts or scars. The most likely diagnosis is:

• A Acne vulgaris, moderate severity
• B Gram-negative folliculitis
• C Malassezia folliculitis
• D Steroid-induced acneiform eruption ✓

Explanation

Systemic corticosteroids classically produce a sudden monomorphic eruption of small papules and pustules on the trunk within weeks of starting therapy. The absence of comedones, the uniformity of lesions, and the temporal link to drug onset distinguish it from true acne vulgaris. Malassezia folliculitis gives itchy uniform papulopustules too but is linked to humidity and immunosuppression rather than a clear drug trigger; KOH scraping settles doubt. Gram-negative folliculitis occurs after prolonged antibiotic therapy for acne.

Reference: Fitzpatrick's Dermatology, 9th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.