Hi,
There are many causes that needs to be ruled out. Are there other signs or symptoms present? Friction is the most common cause wherein skin rubbing against skin generates heat and sweat which could lead to redness and pain. Fungal infection, on the other hand, thrive in warm and moist areas.Diagnosis is usually through obtaining skin scrapings of the lesion and evaluating it under the microscope.
If caused by fungus, the redness and associated itch will be more gradual. This has a tendency to recur. Treatment of fungal infection may requires about 4 weeks of local antifungal medications. It would be best to have it evaluated by your doctor for proper management. Take careand keep us posted.
my 13 year old son has the exact same thing right now and I just spoke with his doctor and he told me to give him some benadryl and put cortisone cream on it. If it did not help within the hour , he wanted me to take him to a emergency clinic because he did not like the way it sounded. I thought I would look on the internet for information before I took him and I came across your post. maybe if I find any info. I will let you know.