scab. 1  An incrustation over a sore, wound, vesicle, or pustule, formed during healing. 2  The mange, especially when it appears on sheep. 3  Any of several different diseases of potatoes producing pits and other damage on their surface, caused by streptomyces bacteria (but formerly believed to be caused by a fungus).
Diabetes complications from fungus infections in the toenails and fingernails can lead to amputations of the entire limbs. To understand how serious fungal toenails can be to a diabetic, you must first understand how diabetes affects the body.
This is the case of people with HIV/AIDS, people under steroid treatments, and people taking chemotherapy. People with diabetes also tend to develop fungal infections. Very young and very old people, also, are groups at risk. Although all are at risk of developing fungal infections, the likelihood is higher in these groups.