[Systemic therapy with anti-infective agents. Principles of rational use of systemic antibiotics in dermatology]

Antibiotics are frequently prescribed and extremely valuable drugs, because they are curative. However, their often incorrect use is the main reason for the increase of multiresistant pathogens. Inappropriate prescription of broad spectrum antibiotics for skin and soft tissue infections favors the selection and spread of multiresistant bacteria not only in the skin, but also in remote visceral organs (e.g. in the intestines), due to their systemic distribution and effects in the body (so-called collateral damage). For this reason basic knowledge and special prudence when using antibiotics are just as desirable as an awareness of responsibility for the public welfare.

This article intends to convey basic knowledge on the indications and selection of suitable antibiotics as well as on the development of bacterial resistance and it gives recommendations for allergological procedures when patients report alleged drug reactions to antibiotics.

Systemic antibiotics for soft tissue infections are indicated when the infection spreads within the tissue so that it is no longer accessible for local antiseptics. In addition to the clinical symptoms, important parameters are high blood sedimentation rates (BSR) and high levels of C-reactive protein (CRP), leukocytosis with neutrophilia and fever (not always present in elderly or immunosuppressed patients). Certain constellations, such as the presence of severe underlying diseases, perfusion disorders or a particular localization (e.g. infection of the face) may necessitate early or parenteral administration. There is no need for systemic administration of antibiotics for uncomplicated wounds without soft tissue infections. Due to their curative effects, the decisive criterion for the use of antibiotics is their sufficient antimicrobial efficacy at the site of infection. An inappropriate administration increases both the selection pressure and costs of treatment and can have fatal consequences in serious situations. In dermatological patients the beta-lactam antibiotics penicillin V, penicillin G and cephalosporins of groups 1 and 2 are the antibiotics most commonly indicated for skin and soft tissue infections. If the patient's history arouses the suspicion of incompatibility to these antibiotics, allergological diagnostics should be carried out in order to avoid as often as possible the alternative use of antibiotics which result in more undesired effects and development of resistance.