Is this stubborn lesion a “callus” - or something else?

Case 2: A 42-year-old woman complains of a “callus” of 6 months’ duration on the thumb of her dominant hand. The persistent lesion responds to the use of a pumice stone and moisturizers but quickly returns.

What do you suspect?

1. Callus.
2. Wart.
3. Dyshidrosis.
4. Psoriasis.
5. Fungal infection.

Answer: Wart
The stubborn lesion was a wart, B, which responds to salicylic acid or cryosurgery. The patient opted for the more expeditious cryosurgery. The lesion did not have the clinical appearance of a callus. Psoriasis and fungal infection eruptions are erythematous and scaly. The lesions of dyshidrosis are vesicular.