Hello and welcome to healthcaremagic I would keep a possibility of fungal infection/tinea cruris. Clinically fungal infection comonly presents as red rings with central clearing and peripheral spreading and scaly rim. Closely opposing body folds e.g finger webs, thighs and groin, axilla, submammary folds etc can trap sweat, heat and moisture, therefore making the area favorable for fungal proliferation. If I was the treating doctor I would have asked to use a topical antifungal like clotrimazole/sertaconazole/luliconazole cream, twice daily, regularly for 4 weeks. An OTC antihistamine e.g cetrizine syp, once daily would help in symptomatic itch relief. regards