in 1952 , wilson1 coined the term " necrotizing fasciitis " ( nf ) for the necrotizing soft tissue infections in which the fascia and tissue death are invariably involved . nf is an infection that spreads along the fascial planes causing subcutaneous tissue death with relative sparing of skin and underlying muscles , characterized by rapid progression , systemic toxicity , and even death2 . histologically , obliterative vascular thrombosis and polymorphonuclear infiltration are initially confined to the deep dermis and superficial fascia3 . liquefactive necrosis of subcutaneous fat , air tracking along deep fascial planes , and vascular thrombosis with resultant skin changes eventually occur . the portal of bacterial entry may be trivial , and patients usually present with pain disproportionate to the visible skin changes2 . presenting symptoms are nonspecific and may include mild cellulitis , edema , and occasionally crepitation2 . at onset , nf can be difficult to differentiate from cellulitis and other superficial infections of the skin4 . studies have shown that only 15% to 34% of patients with nf have an accurate admitting diagnosis5 . patients with nf usually demonstrate systemic effects , initially presenting with fever ( temperature greater than 38 ) , tachycardia , diaphoresis , and possibly even an altered mental state or diabetic ketoacidosis . the physical examination should include all parts of the body in a search for skin inflammation . misdiagnosis and delayed treatment can result in death from sepsis , mediastinitis , carotid artery erosion , jugular vein thrombophlebitis , or aspiration pneumonia6 . nf is associated with systemic toxicity and high mortality rate if not treated timely and aggressively . our department experienced an nf patient who showed severe skin infection around the neck and required several operations . a 85-year - old female patient visited our emergency room due to painful swelling on the bilateral submandibular , submental , and upper neck areas . several days previous , she underwent endodontic treatment on a lower central incisor . after the treatment , however , her symptoms persisted , and swelling developed suddenly . she was febrile , with a body temperature of 39. no other medical condition was significant except a medical history of steroid due to arthralgia . laboratory findings were a white blood cell ( wbc ) of 10.2610/l , erythrocyte sedimentation rate ( esr ) of 3 mm / hr , neutrophil of 93.1% , activated partial thromboplastin time ( aptt ) of 45.9 seconds , and a c - reactive protein ( crp ) of 202.96 mg / l ( table 1 ) , suggesting an acute infected state . comuted tomography ( ct ) was performed and showed a disseminated deep neck abscess in the left submandibular space that extended into the upper mediastinum through the anterior neck space and to the supraclavicular and axillary areas.(fig . 3 ) by incising the submental and submandibular areas and dissecting with fingers and mesenbaum scissors . when the underlying fascia was opened , a small amount of pus was discharged , and the fascia was noted to be a discolored grayish color . these findings suggested fasciitis rather than odontogenic abscess . to drain the anterior neck and superior mediastinum , we incised the skin along the anterior border of the sternocleidomastoid muscle , revealing that that entire fascia along the anterior neck and carotid sheath was discolored to grayish . with a scissors and fingers , we detached the diseased fascia from the submental area to the upper mediastinum . to drain the supraclavicular and axillary areas , we incised the supraclavicular area and the anterior border of the trapezius muscle , and the infected areas were explored . silicon drains were inserted , and the patient was administered a triple antibiotic regimen of penicillin , aminoglycoside , and metronidazole . on microscopic examination , acute and chronic infection was found , and lymphocyte infiltrations were noted in the necrotic fascia . after 4 days , the patient 's condition was not improved , and ct showed that the infection had spread under the trapezius muscle . laboratory findings were wbc of 13.1810/l , esr of 15 mm / hr , neutrophil of 87.7% , aptt of 46.3 seconds , and a crp of 151.46 mg / l.(table 1 ) we drained the area under the trapezius muscle and obtained an artificial airway through tracheostomy.(fig . 4 ) we incised the anterior border of the trapezius muscle to a greater extent than in the original surgery , incised the suprascapular area , and inserted the drain through and through.(fig . after the operation , the patient was sent to the intensive care unit and and administered ventilator therapy for respiratory support . after 10 days , the skin infection had extended to the upper chest and shoulder area . follow - up ct images showed that the multifocal abscess around the left chest wall , shoulder area and carotid area had further deteriorated.(fig . 5 ) laboratory findings were a wbc of 12.2110/l esr of 11 mm / hr , neutrophil of 75.7% , aptt of 38.6 seconds , and a crp of 14.2 mg / l.(table 1 ) we suspected uncontrolled nf , as there was no significant gross interval change in the multispace abscess or nf . we immediately performed a third operation in which we incised the skin on the chest over the healthy area and dissected the infected skin . once the skin was elevated , we noted that the subcutaneous fat and superficial fascia were all necrotized . with finger dissection , the carotid space was dissected ; all necrotic tissue around the upper chest and trapezius area was dissected with messenbaum scissors . pus culture at this operation showed that the main microorganism was actinibacter baumanni , which is resistant to cabepenem and most antibiotics . 7 ) although the infection subsided after the third operation , the skin over the distal clavicular area was not able to be salvaged . using a bilobed rotational flap , the skin was closed on postoperative 37 days.(fig . 8) the tracheostomy tube was removed on postoperative 40 days . laboaratory findings on the day of discharge were a wbc of 10.0810/l esr of 5 mm / hr , neutrophil of 71.3% , aptt of 25.7 seconds , and a crp of 20.4 mg / l.(table 1 ) the wbc was not high , but crp and aptt were extremely high , suggesting a recovery pattern related to reduced crp and aptt . it is generally accepted that predisposing factors to nf include diabetes , alcoholism , tobacco abuse , immunosuppression , malnutrition , advanced age , peripheral vascular disease , renal failure , underlying malignancy , and obesity7 . precipitating events of nf include surgery , minor invasive procedures ( e.g. , joint aspiration and acupuncture ) , intravenous drug use , penetrating injuries ( e.g. , insect and animal bites ) , soft tissue infection , burns , and child birth4 . nf in the head and neck region is rare , with most cases having an odontogenic origin7 . other causes of nf reported in the literature are tonsillar or pharyngeal infections , trauma , cervical adenitis , salivary gland infections , and tumor infection8,9 . cervicofacial nf is rarely initially suspected because the disease is uncommon , the presenting signs and symptoms are often benign , and there is frequently a dental infection or pharyngitis thought to explain the findings6 . in the presented case , patient had been administered corticosteroid due to arthralgia , which reflected an immunocompromised state , and the infection was induced by minor endodontic treatment . the patient was initially diagnosed with odontogenic infection , but necrotic fascia confirmed fasciitis . according to quereshy et al.7 , oral streptococcal species are cultured from most nf , with staphylococcal and anaerobic organisms also occasionally identified . these infections appear to be caused by the same species of bacteria that cause chronic dental subapical infections , acute localized cellulitis , and tissue abscess . the classical infectious nf process usually begins 2 to 4 days after the initial insult . true nf features rapid , progressive liquefaction of the subcutaneous fat and connective tissue , while the overlying skin is spared . necrosis and liquefaction of fascia and fat occur early in the process , possibly mediated by the collagenase and hyaluronidase produced by group a streptococci . this liquefaction of fat results in separation of the skin from the underlying tissues , producing edematous fluid and the pathognomonic " dishwater pus , " which has an offensive odor in the presence of anaerobes . if not swiftly managed surgically , infectious spread along the fascial planes of the neck can widely undermine the skin into the face and thorax . further necrosis and liquefaction of the fat and fascia lead to arterial thrombosis , wet gangrene , and finally ischemic death of the skin . inflammatory factors lead to fever , tachycardia , and eventually , septic shock10 . in the presented case , although all of the subcutaneous fat and superficial fascia were necrotized , only a small portion of the skin was necrotized , though to be due to lack of blood supply . the incision is typically placed at the margin of the skin erythema area , where ample blood supply is difficult . clinicians must know that nf may accompany weakness , apathy , confusion , fever , tachycardia out of proportion to temperature elevation , hypotension , volume depletion , hypocalcemia due to calcium sequestration into areas of fat necrosis , and increased glucose level from increased gluconeogenesis from protein and hypoproteinemia11 . green et al.2 listed fever and signs and symptoms of systemic toxicity as diagnostic features of nf , including high fever , hypotension , prostration , and multiple organ failure . the condition is known as streptococcal toxin shock syndrome . the clinically diagnosis of nf in the head and neck can be very difficult , especially in the initial stage , as the symptoms may resemble those of simple cellulitis or erysipelas . the distinguishing features are fast progression , pain , systemic toxicity , and presence of subdermal gas . if muscle is primarily infected , then the diagnosis of streptococcal myositis or gas gangrene should be considered13 . examination of a patient with nf will often show a lack of integrity of the subcutaneous fat , offering little resistance to the exploring finger . the skin will often feel undermined by the progressive infection11 . when nf is suspected , prompt ct examination is mandatory . among the other diagnostic radiography techniques , ct scan is more sensitive than other imaging modalities because it shows inflammatory changes , such as fascial edema and thickening or abscesses . in contrast to abscess , nf shows an area of fluid accumulation without significant rim enhancement at the periphery14 . although gas accumulation is not a consistent finding , gas in the tissues had been considered a hallmark of nf . another ct feature that may be considered characteristic of nf is a bizarre - shaped hypodense area , often irrespective of the cervical fascia compartment , that does not show significant rim enhancement on contrast injection14 . this feature is distinguishable from an abscess , which appears as a single or multilobulated area of fluid attenuation , usually confined to one compartment and typically showing peripheral rim enhancement . the bizarre shape of the hypodense area has been suggested to be caused by rapid spreading of the liquefaction necrosis across multiple layers of cervical fascia15 . in the presented case , a hypodense area without rim enhancement was observed , which is not characteristic of odontogenic abscess , and showed a small amount of pus , again in contrast to abscess . treatment involved securing the airway , broad - spectrum antimicrobial therapy , intensive care support , and prompt surgical debridement , repeated as needed14 . airway management is critical with cervicofacial nf because the disease process may produce neck edema and necrosis , which increase the difficulty of intubation . often with nf , extended airway management is warranted ; in such situations , a tracheotomy is preferred over an endotracheal or nasotracheal tube11 . gram staining may be helpful for selecting first - line antibiotics , and results of blood culture will most often be positive10 . antibiotic therapy should be adjusted in response to culture results , but early triple - antibiotic therapy is the current standard of care11 . reducing mortality rests on early diagnosis and prompt aggressive treatment . the early incision and debridement of all involved spaces can salvage the skin , which may still succumb to necrosis later in the disease course due to thrombolization of feeding vessels12 . the initial goals of surgical debridement are to eradicate all necrotic tissue and drain loculated collections and fluid in the fascial planes . because of the rapid progression of this disease , serial debridement is often performed under general anesthesia in the operating room within the first 24 hours after the initial debridement2 . in addition , wounds should be irrigated each time the dressing is changed , and one should be observant for the redevelopment of necrosis16 . general agreement is that the defects should be kept open , and debridement should be repeated until completely healthy granulating tissue is obtained17 . on average , appropriate nutritional support , pain management , fluid resuscitation , and replacement of electrolytes are important measures for patient survival11 . unfortunately , septic shock can develop , which will lead to multiple organ failure and death18 . major complications from nf are mediastinal involvement , septic shock , pleural effusion , lung empyema , airway obstruction , rupture of major vessels , brain abscess , disseminated intravascular coagulopathy , sepsis , acute renal failure , and respiratory failure . usually , such complications in immunocompromised patients , such as diabtes mellitus and cancer patients , lead to death7,14 . banerjee et al.19 found that 44% of the cervical nf cases in their series had mediastinal involvement , 38% of whom died of the disease . infection can propagate from the head and neck to the mediastinum through the retropharyngeal or prevertebral space or can descend along the carotid sheath . direct downward extension of fasciitis involving the pretracheal fascia can also result in mediastinal or pleural involvement20 . primary closure can be performed with various local flaps , skin graft , regional flaps and even free vascularized flaps16 . in the presented case , the wound margin was necrotized ; after ample delay , the wound was reconstructed using a local flap .