Any diabetic has a risk of a grave problem whenever there is a injury
especially to the legs. In Diabetics the wound healing
is disrupted and infections tend to heal more slowly. In your friends case I would advice you to consult a doctor ASAP, and take necessary antibiotics and dressing as per doctors advice. Delay in this can lead to serious problems and yes amputations in rare cases as well.
Dr. Om Lakhani, MD