Hello, welcome to health care magic. I am Dr Alok Sinha, MD Psychiatry from India. I will try my best to answer your query. I have carefully read your question. It is good that you want to know more about illness of your husband. I understand your concern. Diabetes is an illness in which our body fails to control the level of glucose because of inadequate insulin secretion. As a result there occurs a hyperglycemic state. There are various mechanisms of increased rate of infection in a diabetic. These are as below:- 1. This increased glucose level act as a good viable media for the growth of pathogens. 2. There is dysfunction of immune system (both cellular and humoral) thus body can not fight with bacteria fungus and virus etc. 3. Blood circulation to various organs and extremities gets compromised in advanced case of diabetes causing gangrene and other infections a potential complication. 4. Peripheral nerve damage causes sensation loss and thus making body susceptible to injury and infection. Red spots at end of penis may be due to some skin infection that may need management by a physician at the earliest. To avoid further infection your husband s blood sugar should be controlled well through diet control, regular exercise, and anti-diabetic drugs. I hope it answers your question. I wish your husband a better health.