I'm a 22 years old male teenager. Since a year ago I've had this reddish (could be purplish) circular patch on the sole of my left foot, near the foot arch. It's about 3 cm in diameter, slightly raised and itchy, but it doesn't have any skin peeling or smell that's associated with fungal infections I used to have. It's aligned to the region between the sole and the normal skin that cover the top of the foot, and doesn't spread towards the top of the foot. I'm not sure if it can spread either, since the itchy region has remained about this size for several months. I've scratched it a lot so it's kinda hardened compared to other parts of my sole.
I've seen a few doctors, of which one carried out a skin scraping test (I think) and it was negative, and according to that doctor it's unlikely to be tinea keratosis. In fact, the itch appears to be more skin-deep, since blisters that formed directly on the patch as a result of scratching and eventually healed did not leave the area with an unaffected zone.
The doctor suspected that it could be fixed drug eruption, but the only drug I've taken, and on rare occasions when I fall sick, are normal paracetemol and chlorpheniramine tablets. Recently I noticed a new patch near the old one (about 2 cm away), with the same slight darkened skin tone of about 0.5 cm in diameter and itch.
The following creams are the ones I've used for around 2 weeks to a month each to no avail:
miconazole nitrate (micronised) 2% w/w
miconazole nitrate mixed with steroid
betamethasone valerate cream BP 0.025% w/w
betamethasone valerate cream BP 0.05% w/w
By no avail, I mean these cream doesn't remove the itch, and doesn't cure the problem.
Can anyone identify this skin problem of mine?