terrible rash

my husband has developed a serious rasg across his groin area. At one point it was clear down his thighs. It has spread under his buttocks and up his crack. Recently i have noticed a similar rash on my inner thighs and buttocks as well. Doctors have prescribed him with an antifungal cream and it helps but it never fully goes away and keeps coming back. What is it and what do we do?

[Bhupinder Kaur, MD]

Hello,
I cannot confirm anything without examination but it is important to rule out erythrasma. Erythrasma is a chronic superficial infection of the intertriginous areas of the skin.It is true that groins are effected but the typical appearance is well-demarcated, brown-red macular patches. The skin has a wrinkled appearance with fine scales.

The standard therapy of erythrasma is antibiotics and antifungals because it is caused by a bacteria C minutissimum.Erythromycin is the drug of choice.

Mild steroids are helpful in reducing the inflammation associated with it. But use it only after a dermatologist’s prescription.
I sincerely hope that helps. Take care and please do keep me posted on how you are doing or if you have any additional doubts. Warm regards.