Complicated skin, skin structure and soft tissue infections: Current therapy recommendations

Tissue infections or skin, skin structure, and deep seated soft tissue infections are general terms for infections of the entire skin layer including the subcutaneous and muscle tissue layers and their respective fascia structures. Infections of the different mediastinal fascias (mediastinitis) and retroperitoneal fascia infections also belong to this category. Due to the variety of their clinical presentation, skin and soft tissue infections can be classified according to different features. The term soft tissue infection is a general term for several disease processes of which some are totally different with regard to the clinical picture, the initiating bacteria and, of course, the surgical and antibiotic treatment. Diagnosis is easily made by the classic parameters of Galen: Pain, redness, warmth, swelling and reduced function. Infection parameters like fever, CRP and leucocytosis are elevated. A standardised technique used to obtain microbiologic cultures from the focus of the infection is pivotal for the accurate identification of pathogens. CT scan, MRT, Ultrasound- or Duplex sonography are only indicated in order to localise the extent of the infection. Overall staphylococci and streptococci are the leading bacteria in soft tissue infections, but infections due to Gram-negative bacilli and/or anaerobes occur in a lot of cases. Many different pathogens, alone or as a part of a polymicrobial infection are involved and will vary depending on the clinical situation, location of the infection and medical history of the patient. Several recent reports identified MRSA as the leading pathogen in SSTIs. It also causes 20% to 50% of diabetes-associated foot infections in several countries and is associated with worse outcomes than other pathogens. The management of soft tissue infections normally involves both surgical debridement and empirical antibiotic therapy. The goal of surgical intervention is to relieve the purulent infection via operative debridement. Necrotic tissue infection requires early radical excision. In special rare cases such as necrotising fasciitis, the principles of the planned re-debridement should be followed. Antibiotic treatment should only be initiated if inflammatory markers are elevated (CRP > 50mg/l, WBC > 10.000/ nl, temperature > 38,5°C) The antibiotic drug should cover Gram-positive and Gram-negative germs and in most cases the anaerobes. The physician has to take into account the pharmacodynamic and pharmacokinetic properties as well as the safety profile of the chosen drug. The surgical procedure should be followed by a standardised wound dressing. Wound dressing must be done according to the physiological phases of wound healing. In the beginning of the exudative phase the wound must be clean and moist. At the end of the treatment the wound should be closed with an aesthetic scar.