6. Krieg:Umbruchvorlage 12.01.2009 9:39 Uhr Seite 35 January 28, 2009 EUROPEAN JOURNAL OF MEDICAL RESEARCH 35 100 % and a specificity of 86 % performed in a group of seventeen patients consisting of eleven cases of necrotizing fasciitis and six cases of cellulites [16]. Thus, supporting that MR imaging rather than CT scanning should be preferred as diagnostic tool in necrotizing fasciitis. To establish the diagnosis of necrotizing fasciitis the correlation of clinical, imag- ing, and laboratory findings is mandatory. As formerly described, a frozen-section or rapid embedding biopsy of suspicious lesions is useful for early definitive diag- nosis and can therefore reduce mortality significantly [22, 23]. Our operative strategy is aggressive debridement with complete removal of all necrotic areas until healthy tissue is exposed. Skin flaps are moderately trimmed and separated from the underlying tissue by surgical towels. Necrotic areas are resected. A daily ex- amination of the wound must be performed in order to asses the local conditions and to exclude a progres- sion of infection and necrosis. Most of our patients presented on admission with typical symptoms of early necrotizing fasciitis such as swelling, erythema, pain out of proportion to physical examination and fever. Signs of a more progressive stage of the disease such as skin necrosis, purulent se- cretion, hemorrhagic bullae formation, crepitus and signs of a compartment syndrome as well as sensory and motor deficiencies were observed only in a minor- ity of patients. Histopathologically, necrosis of the su- perficial fascia combined with angiothrombosis and suppuration are characteristic [11, 12]. Thereby subcu- taneous fat necrosis mostly without major changes of the epidermis occurs as well as inflammation of the dermis and subcutaneous fat with infiltrating leuco- cytes. Bakleh and associates [13] concluded from a group of 63 cases with necrotizing fasciitis that histopathological findings and clinical course may cor- relate and established a model of three stages. In our study the most common infection was a type I-polymicrobial infection with a prevalence of 53.8 %. In 30.8 % of our patients with type I infections, cul- tures grew also anaerobes. Patients with positive anaerobic cultures needed more surgical revisions, sug- gesting that especially these patients might profit from a hyperbaric oxygen therapy (HBO) in the adjuvant therapy of necrotizing fasciitis. A reduction of mortal- ity and a decreased need of debridements were report- ed [24-27]. In particular, patients suffering from infec- tions with anaerobes may benefit from HBO therapy because of the direct toxic effect of increased free radicals through increased oxygenation in the hypoxic tissue area [28]. The classification of physical status according to the American Society of Anaesthesiologists [18] corre- lates with perioperative mortality or postoperative out- come [29, 30]. So far, the prognostic value for patients suffering from necrotizing fasciitis had not been shown. We found a correlation between ASA status and days on the ICU, days on the respirator, and sur- vival. Necrotizing fasciitis remains a major challenge for several reasons. While it is of utmost importance to diagnose the disease early in its course, the signs may be very unspecific and less severe conditions such as cellulitis or may be considered. Once the suspicion of necrotizing fasciitis is raised immediate action is re- quired. The diagnosis and extent have to be estab- lished. Resection of all affected fascia may require the resection of large segments of viable skin and subcu- taneous tissue. The problems are particularly striking in type II necrotizing fasciitis, where typical foul- smelling dishwater pus is missing. In order to overcome these difficulties, we institut- ed a “necrotizing fasciitis alertness” team, including an experienced staff member, which is supposed to see all patients who are under suspicion immediately after admission. If immediate diagnosis cannot be estab- lished, diagnostic procedures like MR- or CT-imaging and fascial biopsy are initiated. In summary, the need for early diagnosis and ag- gressive therapy has been stressed before in the litera- ture [7, 8, 19, 20]. We confirm this approach. Our di- agnostics consisted of three steps: examination by a surgical infectious disease specialist, CT-or MR-scan and, if necessary, a biopsy, processed by rapid embed- ding. This allowed us to submit all patients to defini- tive therapy within 24 hours. In one case the diagnosis was substantiated by a biopsy prior to major surgery, in 10 cases the nature and extent of the disease was determined by CT-scan, showing a limited diagnostic validity. If anaerobes are isolated in necrotizing fasci- itis an early and aggressive second look is necessary. At the same time, however, the basis of timely therapy is a high level of suspicion with no diagnostic tool be- ing superior to clinical judgement. REFERENCES 1. Wilson B. Necrotizing fasciitis. Am Surg. 1952 Apr;18(4):416-31. 2. Singh G, Sinha SK, Adhikary S, Babu KS, Ray P, Khanna SK. Necrotising infections of soft tissues-a clinical pro- file. Eur J Surg. 2002;168(6):366-71. 3. Green RJ, Dafoe DC, Raffin TA. Necrotizing fasciitis. Chest. 1996 Jul;110(1):219-29. 4. Giuliano A, Lewis F Jr, Hadley K, Blaisdell FW. Bacteri- ology of necrotizing fasciitis. Am J Surg. 1977 Jul;134(1):52-7. 5. Chen JL, Fullerton KE, Flynn NM. Necrotizing fasciitis associated with injection drug use. 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