Question:

This is the right sole of a 34-year old lady. She complains of some mild pain over the sole for the past two months. She noted that there was a skin rash which thickened and was enlarging gradually. She has tried to pare herself to remove the skin rash without success.

Answer: C. Mosaic wart

This lady is suffering from plantar mosaic wart. These plaque like hyperkeratotic lesions are often extensive. They are made up of multiple, tightly packed but discrete individual viral warts on the soles. Unlike the solitary hyperkeratotic plantar wart, the pain may be minimal. There are fine black dots on the surface of mosaic warts. They are the end-on view of fine capillaries of the wart. Plantar corn has a whitish central core without black dots especially after paring off the thickened skin. Malignant melanoma of the extremities - the acral-lentiginous type is the commonest type of melanoma found locally. If in doubt, a skin biopsy is justified. Black heel often develops after some blunt trauma or shearing stress over that part of skin at the heels e.g. playing volleyball, tennis etc. There will be a sudden shower of minute black punctate macules. They are often found on the posterior edge of the plantar surface of one or both heels. It will disappear with time and treatment is not necessary.