Single red lump on knee.

For at least 2 years I have had a cirular red (not entirely symmetrical) mark on the inside of my knee measuring just under 1cm in diameter. It has two tiny red lumps in the middle. It is not painful to touch and does not get incredibly bigger but does change colour occasionally. I was diagnosed with ringworm on the first occasion when I visited my doctor. I then saught a second opinion from another doctor who said it wasn't ringworm but did not know what it was. Please advise.

[Bhupinder Kaur, MD]

Hello,
It can be due to nummular dermatitis or granuloma annulare. Granuloma annulare is a chronic disease consisting of a rash with reddish bumps arranged in a circle or ring. Usually it is asymptomatic but due to cosmetic disfigurement topical or oral steroids may be needed. Please discuss this with your dermatologist.

It is very difficult to precisely confirm a diagnosis without examination and investigations and the answer is based on the medical information provided. For exact diagnosis, you are requested to consult your doctor. I sincerely hope that helps. Take care and please do keep me posted on how you are doing.