Diabetic patients suffer from recurrent episodes of infections. The ce
llular and the humoral elements of the defense system against germ inv
asion are disturbed by the diabetic metabolism. Neuropathy and vascula
r 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 di
agnosis and therapy. Dehydration, electrolyte disturbances, malnutriti
on, 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. Altere
d every-day-life with modified food intake and reduced physical activi
ty complicate diabetes therapy. Neuropathy, angiopathy, retinopathy, n
ephropathy and other diabetic complications can be triggered and aggra
vated during the course of an infection. To disrupt this vitious circl
e of hyperglycemia enforcing infections, which then raise blood glucos
e, it is necessary to know about the characteristic features of the in
teractions of diabetes and infection.