Welcome and thanks for your question
I would be pleased to help you with your Question
Thanks for the history provided. It looks like an Fungal infection
, Contact dermatitis
, Intertrigo .
It will need to be examined by the Dermatologist
and you can discuss the above with him .
Possible treatment options include topical anti fungal creams prescribed by the Dermatologist . He might need oral anti fungals and anti itch anti histamines
as well .
Thanks and Take care