[Susceptibility to infections in diabetes--effects on metabolism]

Diabetic patients suffer from recurrent episodes of infections. The cellular and the humoral elements of the defense system against germ invasion are disturbed by the diabetic metabolism. Neuropathy and vascular damage promote the development of wounds and inhibit their healing. Altered motility of the gastrointestinal and the urinary tract lead to increased penetration of bacteria even there. Rare bacteria, atypical courses and frequent complications of infections result in delayed diagnosis and therapy. Dehydration, electrolyte disturbances, malnutrition, and reduced general conditions even increase susceptibility to an infection. On the other hand, an infection deteriorates the metabolic situation in diabetes, resulting in the need for higher insulin doses, or insulin injections in patients normally on oral medication. Altered every-day-life with modified food intake and reduced physical activity complicate diabetes therapy. Neuropathy, angiopathy, retinopathy, nephropathy and other diabetic complications can be triggered and aggravated during the course of an infection. To disrupt this vitious circle of hyperglycemia enforcing infections, which then raise blood glucose, it is necessary to know about the characteristic features of the interactions of diabetes and infection.