Definition Necrotizing fasciitis is a rare, often fulminant, rapidly progressive infectious process primarily involving the fascia and subcutaneous tissue. The pathophysiology involves the rapid spread of infection along the fascial planes, fascial necrosis and thrombosis of the subcutaneous blood vessels, leading to cutaneous gangrene. Approximately 500 to 1500 cases reported annually in the US. The most often associated comorbities are diabetes mellitus and peripheral vascular disease. It is most often peripheral, involving the lower limb. Delay to diagnosis is one of the most prominent predictors of mortality (along with diabetes). Prognosis for necrotizing fasciitis depends heavily on early recongnition and determination of the extent of necrosis in the preoperative planning. Clinical studies are lacking that compare different imaging modalities to the gold standard of fasciotomy. These series are typically small and only look at a handful of cases. Diagnostic Radiology/Musculoskeletal Imaging/Infection/Necrotizing fasciitis From Wikibooks, the open-content textbooks collection

E-Medicine 2005 Necrotizing Fasciitis Michael Maynor, MD, Clinical Assistant Professor, Department of Hyperbaric/Emergency Medicine, Louisiana State University School of Medicine For more than a century, many authors have described soft tissue infections. Their occurrence has been on the rise because of an increase in immunocompromised patients with diabetes mellitus, cancer, alcoholism, vascular insufficiencies, organ transplants, HIV, or neutropenia. Necrotizing fasciitis can occur after trauma or around foreign bodies in surgical wounds, or it can be idiopathic, as in scrotal or penile necrotizing fasciitis. Necrotizing fasciitis has also been referred to as hemolytic streptococcal gangrene, Meleney ulcer, acute dermal gangrene, hospital gangrene, suppurative fascitis, and synergistic necrotizing cellulitis. Fournier gangrene is a form of necrotizing fasciitis that is localized to the scrotum and perineal area. Necrotizing fasciitis is a progressive, rapidly spreading, inflammatory infection located in the deep fascia, with secondary necrosis of the subcutaneous tissues. Because of the presence of gas-forming organisms, subcutaneous air is classically described in necrotizing fasciitis. This may be seen only on radiographs or not at all. The speed of spread is directly proportional to the thickness of the subcutaneous layer. Necrotizing fasciitis moves along the deep fascial plane. These infections can be difficult to recognize in their early stages, but they rapidly progress. They require aggressive treatment to combat the associated high morbidity and mortality. The causative bacteria may be aerobic, anaerobic, or mixed flora, and the expected clinical course varies from patient to patient.

Necrotizing Fasciitis From Apophysomyces elegans Infection Following Trauma from Infections in Medicine Posted 08/08/2002 Lorraine M. Dowdy, DO, Jose G. Castro, MD, Carlos Duchesne, MD, Timothy Cleary, MD Abstract Following a motorcycle accident, a 29-year-old man had fixation of a femoral fracture with an intramedullary rod. After he was discharged, the wound deteriorated rapidly and did not improve despite multiple debridements and antibiotic therapy. Apophysomyces elegans grew on cultures, and treatment with amphotericin B was followed by healing and plastic reconstruction.

Necrotizing Fasciitis of the Upper Extremity Resulting From a Water Moccasin Bite from Southern Medical Journal Posted 12/30/2002 Michael F. Angel, MD, Feng Zhang, MD, PhD, Matthew Jones, BS, James Henderson, MD, Stanley W. Chapman, MD Abstract and Introduction Abstract Aeromonas hydrophila infection has been described as the cause of necrotizing fasciitis in patients with suppressed immune systems, burns, or trauma in an aquatic setting. We report a case in which severe necrotizing fasciitis involving hand, arm, chest, and lateral side of trunk, along with toxic shock, developed after the patient was bitten by a venomous snake. Mixed aerobic and anaerobic bacteria, including A hydrophila, were isolated from the wound culture. The patient was treated with antivenom, a diuretic regimen, broad spectrum antibiotics, and 18 separate surgical procedures. After the application of skin grafts, the wound completely healed. This case illustrates that a venomous snakebite may result in infection with A hydrophila and can cause severe necrotizing fasciitis. Early and aggressive surgical intervention should be implemented as soon as the necrotizing fasciitis is diagnosed.

Lisa Banks Presentation to New York College of Podiatric Medicine Surgical Club

Family Practice Notebook Necrotizing Soft Tissue Infection Necrotizing Fasciitis Fournier's Gangrene Definitions Necrotizing Fasciitis Deep subcutaneous infection Fournier's Gangrene Massive infection and swelling of scrotum and penis Extends into perineum or abdominal wall, and legs Pathophysiology Infection spreads between fascia and SQ tissue Fibrous bands prevent infectious spread Present in head and distal extremities Lacking in trunk and proximal extremities Risk factors Age over 50 years Malnutrition Hypoalbuminemia Alcoholism Immunocompromised state Cancer Corticosteroid use Poor vascular supply Peripheral Vascular Disease Diabetes Mellitus Skin trauma Burn Injury Trauma Intravenous Drug Abuse Recent surgery Miscellaneous risk factors Obesity Break in Gastrointestinal or Genitourinary mucosa Colon Cancer Diverticula Hemorrhoids or Anal Fissure Urethral tear Symptoms and Signs progression (in order of occurrence) Pain and Unexplained fever Swelling Brawny edema and tenderness Dark red induration Bullae filled with blue or purple fluid Skin friable, bluish, maroon, or black Extensive thrombosis of dermal blood vessels Extension to deep fascia leads to brown-gray appearance Rapid spread along fascial planes, veins and lymph Toxicity, shock, and multi-organ failure Signs: Distribution Extremities (53%) Perineum or buttocks (20%) Trunk (18%) Head and neck (9%) References Bosshardt (1996) Arch Surg 131:846-52 Etiologies Group A Streptococcus (Streptococcus Pyogenes) Begins deep at non-penetrating minor trauma Contusion seeded by transient bacteremia Gas production only if mixed infection Severe toxicity, renal Impairment may precede shock Myositis in 20-40% cases Creatine Phosphokinase (CPK) is markedly elevated Mortality: 20-50% despite Penicillin Mixed aerobic and Anaerobic Bacteria Break in Gastrointestinal or Genitourinary mucosa Fournier's Gangrene Comorbid conditions associated with mixed infection Diabetes Mellitus Peripheral Vascular Disease Staphylococcus aureus Clostridium perfringens Hyperbaric Oxygen treatment may help in Gas Gangrene Diagnosis: Findings Suggestive of Necrotizing Fasciitis Fever (Temperature over 100.4 F) Soft tissue erythema, edema and severe pain Vessicles, Bullae or Necrosis Crepitation is only variably present Labs Complete Blood Count White Blood Cell count over 16,300 per mm3 Hemoglobin less than 10 mg/dl Platelet Count <150,000 per mm3 Serum Electrolytes Serum Sodium under 135 meq/L Serum Calcium under 8.4 mg/dl Coagulation Studies Prothrombin Time (PT) prolonged Partial Thromboplastin Time (aPTT) prolonged Arterial Blood Gas Arterial pH <7.35 Differential Diagnosis See Skin Infection (Pyoderma) Cellulitis Erysipelas Necrotizing Insect Bite (e.g. Brown Recluse Spider) Management: Surgical exploration to fascia and muscle Early exploration within 12 hours is critical Observe for Necrotizing fasciitis Myositis Gangrene Technique Visualize deep structures Remove necrotic materials Reduce compartment pressure Send material for Gram Stain and Culture Management: Empiric Combination Regimen (3 drug therapy) Anaerobe coverage Clindamycin 600-800mg IV q8h or Flagyl 750mg q6h Gram Positive coverage Ampicillin or Penicillin Gram Negative coverage Gentamicin 1.0-1.5 mg/kg q8h (after 2mg/kg load) Single agent regimen Ceftriaxone 2 g IV every 12 hours Ampicillin-Sulbactam (Unasyn) 2-3g IV q6h Ticarcillin-Clavulanate (Timentin) Piperacillin-Tazobactam (Zosyn) Combination for Penicillin allergic patient Vancomycin and Gentamicin or Aztreonam Alernative combination protocol Ceftazidime (Fortaz) and Clindamycin or Metronidazole Other measures Maximize nutritional status References Elliott (2000) Am J Surg 179:361-6 Headley (2003) Am Fam Physician 68(2):323-8 Wall (2000) J Am Coll Surg 191:227-31

Necrotizing Soft Tissue Infections: A Guide to Early Diagnosis and Initial Therapy Posted 10/15/2003 South Med J 96(9):900-905, 2003. James A. Majeski, MD, PHD, Joseph F. John Jr., MD
Abstract and Introduction Abstract Necrotizing skin and soft tissue infections are caused by many different bacteria, are frequently polymicrobial, and may have a deceptively innocent early clinical presentation. Clostridial and nonclostridial necrotizing infections are frequently similar in their early presentation. The initial presentation of these infections can be insidious, which results in delay in diagnosis and the start of therapy. The clinician must use sound medical principles of clinical history and meticulous examination in each patient, combined with constant suspicion, to establish a timely diagnosis. This group of infectious diseases is associated with frequent morbidity and significant mortality rates, which increase with any delay in the diagnosis and the initiation of medical and surgical therapy. Also associated with these necrotizing infections is an excessive index of litigation. This review is intended as a guide for the clinician in making an early diagnosis of any necrotizing skin and soft tissue infection and initiating effective medical and surgical therapy.

Rapidly progressive necrotising fasciitis following a stonefish sting: report of two cases Journal of Orthopaedic Surgery 2006; 14(1): 67-70 (full text

The role and effectiveness of adjunctive hyperbaric oxygen therapy in the management of musculoskeletal disorders. Wang J, Li F, Calhoun JH, Mader JT Department of Orthopaedics and Rehabilitation, University of Texas Medical Branch, Galveston, TX 77555-1115, USA. The management of musculoskeletal disorders is an increasing challenge to clinicians. Successful treatment relies on a wide range of multidisciplinary interventions. Adjunctive hyperbaric oxygen (HBO) therapy has been used as an orthopaedic treatment for several decades. Positive outcomes have been reported by many authors for orthopaedic infections, wound healing, delayed union and non-union of fractures, acute traumatic ischemia of the extremities, compromised grafts, and burn injuries. Severe side effects have also been reported with this therapy. To aid in the use of HBO therapy in orthopaedics, we reviewed 43 papers published in the past four decades and summarised the mechanisms, effectiveness, indications and contraindications, side effects, and cost impact of adjunctive hyperbaric oxygen therapy in the management of difficult musculoskeletal disorders. Adjunctive HBO therapy is an effective treatment modality for the management of some severe and refractory musculoskeletal problems. If appropriate candidates are carefully identified, hyperbaric oxygen is a limb- and sometimes life-saving therapy. HBO therapy significantly reduces the length of the patient's hospital stay, amputation rate, and wound care expenses. Thus, it is a cost-effective modality. A clinician must understand the side effects and risks of HBO treatment. Close monitoring throughout the treatment is warranted to minimise the risk to the patients. (full text available)

Salvage of Limb and Function in Necrotizing Fasciitis of the Hand: Role of Hyperbaric Oxygen Treatment and Free Muscle Flap Coverage
South Med J 95(2):255-257, 2002 James C. Yuen, MD, Zuliang Feng, MD Division of Plastic Surgery, Department of Surgery, University of Arkansas
Abstract We report a case of necrotizing fasciitis of the hand treated by urgent debridement followed by serial debridements, hyperbaric oxygen, and delayed free muscle flap coverage. After control of the infection, a major soft-tissue defect remained on the dorsum of the wrist and hand, exposing all extensor tendons. A rectus muscle free flap was used for wound coverage and salvage of the exposed tendons; the muscle flap was covered with a delayed skin graft. The patient regained satisfactory function with ability to extend all digits. This case emphasizes the importance of aggressive debridement and hyperbaric oxygen treatment and shows the valuable role of free muscle flap wound coverage for preservation of function in cases of necrotizing fasciitis of the hand. (more, full text)

Severe necrotising soft tissue infections in orthopaedic surgery Journal of Orthopaedic Surgery10(2):108–13 JC Theis, J Rietveld, T Danesh-Clough Department of Orthopaedic Surgery, Dunedin School of Medicine, PO Box 913, Dunedin, New Zealand PURPOSE. To review all cases of necrotising infection managed in the Department of Orthopaedic Surgery of Dunedin Hospital in New Zealand between 1989 and 1998. METHODS. Hospital records were analysed for predisposing factors, clinical features, diagnostic results, treatment strategies, and outcomes. RESULTS. 13 cases (9 males and 4 females) of necrotising infection were identified. The mean age was 48 years (range, 8–76 years). Presenting symptoms included painful swelling, erythema, and necrosis. Most patients had predisposing factors and had received nonsteroidal anti-inflammatory drugs before presentation. 12 patients underwent surgical debridement including a total of 4 amputations. Septic shock developed in 9 patients who required dialysis for renal failure. Four patients died. The most common organisms identified were group A beta-haemolytic streptococci. CONCLUSION. Severe necrotising infections require a high index of suspicion and rapid medical and surgical intervention to reduce the mortality and morbidity.

Wheeless Textbook of Orthopaedics Discussion: - caused by non hemolytic Strep and hemolytic Staph aureus; - although staph alone may show up on culture, special attention may must be paid to isolating the microaerophilic Streptococceae; - necrotizing fascitis may occur, especially in diabetics; - any hand infection that does not respond to local drainage, wet dressings, and antibiotics should be suspected of having a symbiotic infection; - if special techniques are not used, the diagnosis of a symbiotic infection will be missed, and Staph aureus, Bacillus pyocyaneus, Proteus, and Enterococci will predominate on culture;

Wheeless' Textbook Synergistic Nonclostridial Anaerobic Myonecrosis - similar to gas gangrene - dishwater pus may be present; - Bacteroides and/or anaerobic streptococci may be present, together with aerobic or facultative grm neg. bacilli; Necrotizing Fasciitis: - serious infection that spreads rapidly along fascial planes and is commonly caused by Staphylococcus aureus or Streptococcus pyogenes; - anaerobes - especially clostridia and bacteroides can also be the cause;