<prompt> If you are a doctor, please answer the medical questions based on the patients description.i have got stretch marks in purple red color since about 5 months...and it is very scratching...doctor says its not a fungus...and he prescribe me propygenta nf cream...its not about the stretch mark but i want to know why it has got infection only on my stretch mark and not anywhere else in my body  <response>: Hi, I understand your query. - Stretch marks appear due to overstretching of skin due to pregnancy, overweight. - The infection in stretch marks seems to be due to- - excessive scratching, the source of infection being from under nails. - try not to scratch, keep the nails clean properly cut. - Chat Doctor. I would suggest application of Newsprint H with moisturizer it will cover most of the organisms for infection. - Avoid excessive sweating, you can use Newsprint H dusting power in case its sweating a lot. -If this does not help, culture of the exudate swab sensitivity would help in selection of specific 