Brief Answer:
Pityriasis Versicolor

Detailed Answer:
Hello and welcome to healthcaremagic

I am Dr. Kakkar. I have gone through your query and I have understood it. I have also looked at the pictures

I would like keep a possibility of Pityriasis Versicolor, which is a superficial fungal infection caused by a yeast Malassezia Furfur, characterized by variably colored patches of brawny scaling and post-inflammatory hypopigmentation.

This infection is common on the chest, shoulder, back as these areas are rich in sebaceous glands on whose secretions the yeast feeds upon. The infection is common in hot humid conditions.

Treatment is single oral dose of an antifungal e.g Fluconazole 400 mg.

OR

Apply a 2% Ketoconazole shampoo over the affected area during bath, lather it well, leave on for 5 minutes, once daily for 5 days

The patches resolve leaving behind post-inflammatory hypopigmentation, which may persist for a few weeks post treatment but would eventually resolve.

Hope this helps

Regards

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