What Causes Recurrent Boils On Thighs And Legs?

Doctor, I am a lady in chennai and 49 years old. I am getting boils regularly for the past few months and they develop quite deep, needing minor surgery and it takes about 3-4 weeks and several dressings to heal. I got boils quite deep, two times on my leg, near about same place and got cured. One more is developing near my thigh now. I want to know the reason for this ailment. And which specialist to consult to get permenant cure