Thanks for posting your query to HCM.
After reading your query the diagnosis I can make out is Pityriasis
versicolor or Tinea versicolor
which is superficial fungal infection
of the skin caused by yeasts. It is characterized by scaly patches of different color which later on becomes discoloured or depigmented areas and is mainly present over the upper trunk.
The most common factor for predisposition of the condition is hot, humid climate. As your sister is residing in Asiatic country so it is quite obvious to have predisposition and recurrence of the problem.
The treatment of this condition is quite simple with Topical antifungals in form of shampoos and cream. If not responding, then can take oral antifungal
drugs such as fluconazole
or een higher and latest drugs under medical guidance.
The main problem remains with patients is of the whitish discoloration or hypopigmentation
which may take several months for repigmentation or to become normal.
The other problem is of recurrence for which your sister can follow a regular hygiene maintenance by avoiding hot and humid environment, wearing loose cotton clothes, ironing the clothes from inside and daily two time bath.
Hope to have provided the best information regarding your sister’s problem.
Dr Sanjay K Kanodia
MD (Dermatology & STD/Venereology)