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What is A 36 years old factory worker developed itchy annular scaly plaques in both groins. Application of a corticosteroid ointment led to temporary relief but the plaques continued to extend at the periphery.The most likely diagnosis is – and explain in detail?
In this question :-


Annular lesion in groins
Scaly
Itching
Extending peripherially


All suggest the diagnosis of dermatophyte infection.
Dermatophyte infection of groin is known as T. cruris.