Necrotising fasciitis of the neck: Unusual presentation with aggressive management – case report with review of literature

Abstract Tonsillitis and peri-tonsillar abscess are common conditions which account for a large proportion of hospital admissions. They may present in a similar way to supraglottitis and retropharyngeal collection. With adequate antibiotic coverage, admissions for tonsillitis have decreased compared to cases admitting with complications. This report shows an unusual presentation of necrotising fasciitis in the neck of a 71-year-old male who presented initially with tonsillitis and later developed into supraglottitis with retro- and parapharyngeal abscess complicated by necrotising fasciitis extending into pleural cavity. The patient required a prolonged stay in the Intensive Care Unit, with airway support including tracheostomy, and underwent repeated surgical drainage followed by sequential debridement (10 times). Radiological investigation and nasopharyngolaryngoscopy plays an important role in contributing to early diagnosis. Agressive debridements and necrotic tissue removal with antibiotic cover are mainstay of treatment.


Introduction
Necrotising fasciitis (NF) is a rare and life-threatening infection which spreads along the fascial planes and subsequently causes necrosis of subcutaneous fat, skin and sometimes muscle. [1] Infection primarily involves the superficial fascia and progresses into surrounding tissues; progress is often fulminant and may involve all soft-tissue components, it can occur after inadequate care of abscesses. Predisposing factors include diabetes, obesity, peripheral vascular disease, chronic renal failure, poor nutritional status, smoking or old age. [1] Head and neck is usually less common site for NF compared to limbs. It is usually secondary to dental, peritonsillar infection which can progress to para-or retropharyngeal abscess and to mediastinum. [2] Retropharyngeal abscess caused by supraglottitis is rare. Presenting features may vary from generalised erythema, oedema of neck or may progress rapidly to shock-like stage. [3] Case report A 71-year-old male was referred to emergency ENT service with a one week history of sore throat and increasing difficulty with swallowing. Other than feeling generally unwell, he had no other symptoms, such as weight loss or fever, neck swelling, reduced mouth opening (trismus) or restriction of neck movements. Breathing was not restricted. He had a background history of previous colorectal cancer, atrial fibrillation and mild mitral regurgitation; he was taking Bisoprolol, Aspirin and Lansoprazole. Otherwise, he usually kept well with no reduction in exercise tolerance.
On initial examination on the night of admission, he was found to have bilaterally enlarged tonsils with surrounding palatal oedema. A diagnosis of tonsillitis was made and he was admitted following the protocol of analgesia, intravenous fluid resuscitation and i.v. antibiotics (i.v. amoxycillin). Vital signs were monitored throughout.
Despite good antibiotic cover, there was no improvement in his symptoms over the next two to three days. A flexible nasopharyngolaryngoscopy on second day of admission revealed a swollen epiglottis with surrounding symmetrical oedema with normal finding on the posterior pharyngeal wall; the diagnosis of supraglottitis was made. The treatment plan was amended according to the microbiologist (gentamycin þ metronidazole added to amoxycilin). Regardless of these measures, the swallowing further deteriorated and the patient developed swelling around the submental and submandibular areas on both sides. Ultrasound examination showed midline swelling, suggestive of oedema and inflammation of the subcutaneous tissues with no obvious fluid/abscess collection identified.
Nasogastric feeding was commenced to improve nutritional status of the patient. Five days following this, respiratory distress was developed with continuous fall in saturations despite oxygen. He was then transferred to Intensive Care Unit for CPAP and was subsequently intubated, ventilated and managed for septic shock. See Table 1 for laboratory results throughout the disease.
Owing to worsening of his condition during nine days of admission and antibiotic cover, he underwent CT scan neck and thorax (Figures 1 and 2) which showed a large retropharyngeal abscess extending from skull base to C7/T1, right-sided pneumonia and large right-sided pleural effusion.
He was taken to theatre for trans-oral surgical drainage of the retropharyngeal abscess which revealed presence of smelly fluid with small amount of pus. The chest drain was inserted by thoracic surgeons draining pus and the patient remained ventilated. Over the next 5 days his breathing efforts did not improve significantly, so tracheostomy was performed followed by a repeat CT scan. The scan    showed collection in the anterior tissues of the neck ( Figure 3). The patient was then taken back to theatre for trans-cervical drainage of the abscess. Intraoperative findings revealed presence of soft tissues with the appearance of fragmented necrotic "cooked meat". Bilateral internal jugular veins were inflamed, but at the time of the surgical intervention still patent. Similar appearance of infection was on the strap muscles, sternocleidomastoid muscles on both sides and the thyroid gland. Both sides of the neck were involved from clavicles (in the natural interfacial spaces) levels IB and II under the skull base and reaching till retropharyngeal space. Skin was not involved. Based on the clinical appearance of tissue and intraoperative picture the diagnosis of necrotising fasciitis was made. All the affected facial planes opened and necrotic tissue was removed. Blood cultures remained negative throughout, initial being performed during the stage of supraglottitis. Neck swabs grew Pseudomonas aeruginosa. Microbiological advice was sought and the antibiotic treatment was changed accordingly to clindamycin þ meropenem þ vancomycin. A day later another CT scan was obtained and revealed locules of gas within the soft tissues as a result of previous surgery. No evidence of mediastinitis was seen. The patient was taken to theatre for daily neck debridement over the course of 10 days. The clinical picture of fasciitis with necrosis progressed for three days, on the 4th day the progression of necrosis stopped. Thereafter six more debridement's and washouts were performed daily.
Patient was weaned off gradually from the ventilator and inotropic support and was then transferred to the ward after 30 days stay in the intensive care unit.
In the ward he had a slow and prolonged recovery. Initially he was weaned off the tracheostomy and oxygen support and eventually underwent capping and decanulation in conjunction with a speech and language therapist.
Percutaneous enterogastric feeding tube (PEG) was inserted for long-term nutrition and feeding. The patient also underwent extensive physiotherapy in the ward, which was later completed in a local rehabilitation centre. PEG tube was removed 6 months after his discharge from the hospital. Twelve months after his discharge from the hospital patient was discharged from our care without any residual impairment.

Discussion
Retro-and parapharyngeal abscess can develop as a complication of tonsillitis, supraglottitis, tuberculosis or other infective conditions in the head and neck.
These deep neck space abscess can be caused by aerobic, anaerobic or Gram negative organisms; [4] in our case Pseudomonas was grown on culture. Since it can lead to life-threatening emergency with potential airway compromise, it is essential to diagnose it at an early stage. [5] Descending cervical mediastinitis is an uncommonly reported presentation of infection originating in the head or neck and descending into the mediastinum, which is fraught with impressive morbidity and mortality rates of 40% or more. [6] Clinical diagnosis of retropharyngeal abscess or necrotising fasciitis can be challenging in early stages. Nasopharyngolaryngoscpopy along with radiological imaging like USS or CT scan plays an important role in early diagnosis. [7] Retropharyngeal abscess turning into necrotising fasciitis in neck is rare because of good vascularisation in the area. [2] Symptoms start rapidly in terms of erythema, neck emphysema and rapid deteoration. [3] Serial wound debridements should be performed to avoid development of septic shock. [8] Drainage material should be examined by microbiologist to guide in empirical treatment. Following initial treatment, antibiotics need to be changed depending on results of aerobic and anaerobic cultures. [2] In our patient medication were changed from ceftriaxone to tazocin followed by meropenem and vancomycin based on culture sensitivity. Retropharyngeal abscesses can be drained via transoral or transnasal approach, and tracheostomy might be required due to the risk of airway compromise. [9,10] The necessity of external drainage has been controversial. If an obvious large abscess is found by a clinical examination, then only drainage should be planned. [4] In our case patient underwent drainage via trans-oral incision followed by trans-cervical drainage and tracheostomy in view of mediastinal extension. Previously a study done in 2003, however, has shown that patients with deep neck infections could be treated successfully with antibiotics alone. [11] Although retropharyngeal abscess is more common in children but there are a number of isolated case reports describing its presentation and management in adult patients. [7,10,[12][13][14] These studies reveal the difficulties in identifying abscess using lateral soft tissue neck X-ray compared to CT findings. [13] They also correlate the difference in terms of management of patients by surgical and non-surgical ways. There is little in the literature about the extension of this abscess into the chest. Trinidade et al. [15] have described a case of Citrobacter freundii pharyngitis infection progressing into retropharyngeal abscess with intrathoracic extension. That case was treated successfully with antibiotics and with a minimally invasive posterior pharyngeal wall incision. Case reports about necrotising fasciitis as a complication of retropharyngeal abscess are rare. Seyhan et al. [2] have described necrotising fasciitis along anterior wall of neck in female with diabetes which later developed into a retropharyngeal collection. We are not aware of any reports of cases of necrotising fasciitis as a complication of supraglottitis together with retropharyngeal collection. We are aware the supraglottitis in our case could have been a secondary phenomenon rather than primary cause of necrotising fasciitis. A recent review of admissions for tonsillitis and neck space abscesses by Lau et al. [16] suggests that there has been a 44% decrease in the tonsillectomy rate from 1991 to 2011 with a 310% increase (p ¼ .01) in admissions for tonsillitis and pharyngitis and a 41% increase (p ¼ .026) in admissions for retropharyngeal and parapharyngeal abscess.
Therefore, there seems to be an increasing trend which had been reflected in our institution over the past 12 months of retropharyngeal abscess requiring invasive surgical management and hence swift diagnosis and prompt appropriate management is vital.

Case literature review
We reviewed various article on Cervical Necrotising Fasciitis (CNF) and found 2627 articles of necrotising fasciitis on Clinical key databases, 408 articles from Pubmed 121 from Medline, 42 from Proquest, 3 from A to Z and 2 from Cochrane search. Our last search completed on 22nd September 2015, when we included cases of CNF leading to mediastinitis and we found out 22 articles (9 with review of literature on CNF) ( Table 2).
CNF is a fulminant infection of soft and connective tissues that spreads along the facial planes, inducing posterior venous and arterial thrombosis, followed by necrosis of the skin and other adjacent tissues. It is associated with a high-systemic toxicity and marked compromise of the general state of the patient, with elevated mortality and morbidity rate. It is an uncommon entity that generally presents in the abdomen or limbs, and much more rarely in the cervical region, with published reports of series of cases of no more than 40 patients. [15,17] Reports of Cervical Necrotising Fasciitis are sporadic, the largest series being 34 cases by Lanisnik et al. [17] Bahu et al. [18] reviewed the published data from 1973 to 1997 and noted a 35% mortality rate for 70 cases of CNF. Although many case reports and case series are available, no large studies exist, and large series have often mixed CNF data with lessaggressive infection cases. Banerjee et al. [19] and Djupesland [20] reviewed cases of head and neck NF and have also pushed to define CNF as a distinct entity with twice the mortality rate (30% to 38%).
A study from France reviewed 45 patients with CNF. Most of them (78%) were of dental origin; the remaining cases were of pharyngeal origin or had occurred after surgery or trauma. [21] This was confirmed by a report of 11 cases by Wong et al. [22] and a report of 12 cases by Whitesides et al. [23] in which all the cases were odontogenic in origin.

Conclusions
Adult patient presenting with acute tonsillitis without previous episodes of recurrent tonsillitis not improving within days on intravenous antibiotic, then one should think of other diagnosis such as supraglottitis or infectious complication in the neck. In such cases nasopharyngolaryngoscopy should be performed to directly visualise the airway and consider imaging of the neck. If there is failure to respond to full medical management early, then CT of the skull base to diaphragm is indicated to rule out the collection in the neck or chest. Early diagnosis of retro/para pharyngeal abscess by CT scan and its evacuation can prevent development of necrotising fasciitis. Failure to respond to treatment should warrant involvement of a senior clinician early in the process and never delay surgical intervention if required. One has to be aware of potential diagnosis of cervical necrotising fasciitis and its seriousness. Liaise closely with microbiology for appropriate anti-microbial management. In case of developed necrotising fasciitis repeated daily debridement of necrotic tissues in deep neck spaces with application of antiseptic solution to all exposed area is necessary for sufficient local control of infection.

Disclosure statement
The study was conducted at University Hospitals Coventry and Warwickshire. The author and co-authors are employed at the same institution. There are no financial interests involved. The article has not been presented before any (continued) professional otolaryngological association and is an original work.