What Causes Premature Greying Of Hair Along With Fungal Infection On Scalp?

Hello i have a 15-17 year old boy and i have noticed he has a dent on his head not big as well as hair loss in the region growing back white ? Should i be worried ? There also came a small fungus in the same region and on the right temple with hair growing white. We went to dermatologist and prescribe a shampoo with oral pills and to use selsum blue and it has not fully gone away.