Periorbital Necrotizing Fasciitis

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Article initiated by:
James Chelnis, MD, Matthew Zhang, Viraj J. Mehta, MD, MBA, Matthew Hollar M.D., Sarah Tanaka M.D., Michael, Mercier, Jeanie Ling M.D.
All contributors:
James Chelnis, MD, Viraj J. Mehta, MD, MBA, Matthew Zhang, Michael T Yen, MD, Cat Nguyen Burkat, MD FACS
Assigned editor:
Michael T Yen, MD
Review:
Assigned status Up to Date
 by Michael T Yen, MD on October 13, 2024.


Periorbital Necrotizing Fasciitis
DiseasesDB
31119
ICD-10
[1]72.6


Disease Entity

Necrotizing fasciitis is a rare and severe soft tissue infection characterized by cutaneous gangrene, suppurative fasciitis, and vascular thrombosis. Periorbital necrotizing fasciitis is a rapidly progressive, highly destructive microbial infection involving the skin, subcutaneous and deep soft tissue, and muscle of the periorbital tissues.

Disease

Periorbital necrotizing fasciitis (ICD-10# M72.6).

Causative Organisms:

Periorbital necrotizing fasciitis is an invasive, synergistic, polymicrobial soft tissue infection. The disease is usually preceded by trauma in patients that have pre-disposing systemic risk factors, most commonly diabetes and alcoholism.[1]The most common organism responsible for necrotizing fasciitis is Group A beta hemolytic Streptococcus (GAS) which has been linked to 50% of cases.  Other organisms responsible for single as well mixed-flora infections were Staphylococcus aureus, Staphylococcus albus, Staphylococcus agalactiae, Streptococcus viridans, Staphylococcus epidermidis, Propionibacterium acnes, Arcanobacterium, Citrobacter, Enterococci, Serratia and Finegoldia.[2] [3] [4] Fungal infections such as Cryptococcus, Candida albicans and aspergillus were isolated in two immunocompetent cases following trauma.[5][6] One case of herpes zoster ophthalmicus complicated by a staphylococcal superinfection in the periorbital area causing necrotizing fasciitis has also been reported. [4]

Risk Factors

The most common inciting factor for periorbital necrotizing fasciitis is penetrating or surgical trauma. Sometimes the injury may be so trivial that the patient is not able to recall it.[7] Other risk factors include upper respiratory illness, acute or chronic bacterial sinusitis, recent ocular or periocular infection, or systemic infection.

General Pathology

Periorbital necrotizing fasciitis results from angiothrombotic microbial invasion and liquefactive necrosis.[8] Collagenases or hyaluronidases exuded from the bacteria are theorized to be involved in the spread of the infection.[9][10] [11][12]Edema and dissolution of the connective matrix in the papillary dermis occurs in the early phase of necrotizing fasciitis.[9] Progressive necrosis of the superficial fascia then develops with subsequent infiltration of deep dermis and fascia by neutrophils. Thrombosis of vessels and occasional suppuration of the veins and arteries coursing through the fascia occurs. Bacteria then proliferate within the resulting environment. Initially, tissue invasion proceeds horizontally due to the avascularity of fascial planes. As the condition progresses, ischemic necrosis of the skin develops, along with gangrene of the subcutaneous fat and dermis.[9][10][11][12] However, muscles, bone, and deeper tissues are usually preserved until advanced disease.

Pathophysiology

Periorbital necrotizing fasciitis is divided into two types on the basis of the results of microbial cultures. Type 1 necrotizing fasciitis is polymicrobial and caused by both aerobic and anaerobic organisms. Type 2 necrotizing fasciitis is caused by single organisms such as Streptococci or Staphylococci or a combination of the two. Type 1 necrotizing fasciitis occurs more often in an immunocompromised host, whereas patients with type 2 necrotizing fasciitis often have normal immune function.

GAS and Staphylococcus aureus are the most commonly implicated organisms. Various virulence factors produced by the offending agent contribute to the aggressiveness of the disease. For example, M protein in the cell wall of the GAS is a super antigen that inhibits antibody-mediated phagocytosis.[13] GAS also secretes exotoxins A and B, which results in protease-induced tissue destruction and toxic shock, thus contributing significantly to the mortality seen with necrotizing fasciitis.[7]

The microbial infection initially spreads along the fascial planes that separate adjacent orbital structures. The loose organization of fibrous connective tissue and neurovascular structures within these fascial planes poses little anatomic barrier to local dissemination. As organisms proliferate, there is a rapid influx of inflammatory cells. The combined action of many potent proteases and other degradative virulence factors expressed by invading organisms and the tissue-damaging enzymes released by host polymorphonuclear (PMN) leukocytes results in severe tissue damage. Ischemia from microvascular thromboses, a common histological feature of human GAS necrotizing fasciitis, may also significantly contribute to tissue damage. 

Diagnosis

The diagnosis of periorbital necrotizing fasciitis is a clinical diagnosis. The presence of pale-red, tense, and swollen periorbital skin in the setting of a febrile patient with a history of recent injury, as well as leukocytosis and associated tissue emphysema, strongly raises the clinical suspicion. However, diagnosis is difficult in the early course of periorbital necrotizing fasciitis because of the subtlety of cutaneous findings.[14][15] One clinical hallmark of necrotizing fasciitis is pain disproportionate to physical exam findings.

The LRINEC (Laboratory risk indicator for diagnosis of necrotizing fasciitis) is considered an effective way  to differentiate advanced soft tissue infections from necrotizing fasciitis. The scoring utilizes lab findings including total white blood count (WBC), C-reactive protein (CRP), hemoglobin level, serum sodium level, serum creatinine level and blood glucose level. A score greater than or equal to 6 indicates that necrotizing fasciitis should be seriously considered. It is worth noting, however, that the LRINEC score was derived from retrospective studies and has not been validated prospectively.[16]

History

The presence of pale-red, tense, and swollen periorbital skin in the setting of a febrile patient with a history of recent injury is typical.  Patients also frequently complain of progressively worsening severe pain. Patients may carry comorbidities causing immunosuppression, in particular alcoholism. 

Physical examination

The ocular examination should include:

  • Best-corrected visual acuity (BCVA).
  • Assessment of a relative afferent pupillary defect (RAPD).
  • Visual field assessment via confrontation.
  • Color vision assessment to assess optic nerve function.
  • Ocular motility and assessment for pain with eye movements. There might be involvement of cranial nerves III, IV, or VI in cases of cavernous sinus involvement.
  • Measurement of intraocular pressure (IOP).
  • Slit-lamp biomicroscopy of the anterior segment if possible to look for signs of exposure keratopathy.
  • Dilated fundus exam is important to exclude or confirm the presence of optic neuropathy or retinal vascular occlusion.


The orbital examination should include:

  • Thorough external examination of the orbital adnexa.
  • Proptosis measurements using Hertel exophthalmometry.
  • Documentation of the direction of any displacement of the globe, resistance to retropulsion on palpation, and whether there is unilateral or bilateral involvement

Signs

Periorbital necrotizing fasciitis first begins with the presence of pale-red, tense, and swollen periorbital skin. The infection then spreads subcutaneously and can progress to cyanosis of the skin. Superficial erythema is typically rapidly progressive and can evolve to supralesional bullae two to three days after the onset of constitutional symptoms such as fever and chills. Serosanguineous fluid may drain from the affected area. Painless ulcers may appear as the infection spreads along the fascial planes in later phases. A circumferential black necrotic eschar and cutaneous plaques may occur. Purpura may be found with or without bullae formation and occasionally with a lack of cutaneous erythema and heat. [17] Tissue emphysema may be evident upon examination. Tambe, et al., emphasize that periocular necrotizing fasciitis may become bilateral due to the minimal resistance offered by the subcutaneous tissue over the bridge of the nose.[18]

Symptoms

The hallmark of clinical diagnosis of necrotizing fasciitis is pain out of proportion to physical findings; the infiltration of microbial agents and their released exotoxins illicit a dramatic inflammatory response that coalesce as pain.[19]

The majority of infected individuals who develop periorbital necrotizing fasciitis also have an existing infection in the periorbital area in a wound or surgical site with delayed healing. The affected periorbital tissue may exhibit pronounced hyperesthesia with associated paresthesia in adjacent areas occurring later in the disease process.

Diagnostic procedures

CT with contrast is the modality of choice for the diagnosis of periorbital necrotizing fasciitis. Radiographic findings in the early stage of necrotizing fasciitis are similar to those of cellulitis. These findings include increased soft-tissue opacity and thickness. However, radiographic findings can also be normal until the infection becomes advanced.[20] [21]CT findings may show dermis thickening, soft-tissue attenuation, fat stranding, and possibly superficial or deep crescentic fluid or air in the subfascial planes.[21][22] [23] [24] [25] [26] The CT hallmark of soft-tissue air with deep fascial fluid collections is not always seen, and its absence should not exclude necrotizing fasciitis from the differential diagnosis.  In these cases, the patient may have early disease in which gas has not yet formed or reached detectable levels.[26]

CT is the most sensitive modality for soft-tissue gas detection, and compared with radiography, CT is superior to evaluate the extent of tissue or osseous involvement, to show an underlying infectious source, and to reveal serious complications such as vascular rupture. [22] [23] [24] [25] [26] Similarly, the rapidity of CT compared with MRI may be advantageous for an emergent necrotizing fasciitis evaluation.

MRI is the preferred modality for evaluation of soft-tissue infections. However, MRI is not often performed for necrotizing fasciitis evaluation as these scans are time consuming and may delay treatment.[26]MRI findings in necrotizing fasciitis include circumferential dermal and soft-tissue thickening that have variable signal intensity on T1-weighted sequences and increased signal intensity on fluid-sensitive sequences.[26][27]Fascial thickening is also hyperintense on fluid-sensitive sequences, such as T2-weighted fat-suppressed spectral presaturation with inversion recovery (SPIR). It typically begins in superficial fascia and extends along the length of the involved muscle compartment.[17] Late-stage gas collections dissecting superficial or deep fascia are seen as punctate or curvilinear T1- and T2-hypointense foci. IV gadolinium contrast material increases sensitivity for tissue necrosis and can be used for more detailed evaluation of soft-tissue involvement.[27][28] [29] [30] [31] [32] However, patients with periorbital necrotizing fasciitis may also present with renal failure; thus, administration of IV gadolinium may not be possible.

Laboratory test

The LRINEC (Laboratory risk indicator for diagnosis of necrotizing fasciitis can be a useful tool in differentiating advanced soft tissue infections from necrotizing fasciitis.

The scoring utilizes the following lab findings:

Total white blood count (WBC per mm3):

  • <15 =0
  • 15-25=1
  • >25=2


C-reactive protein (CRP):

  • 150 =0
  • >150=4


Hemoglobin level:

  • >13.5=0
  • 11-13.5=1
  • <11=2


Serum sodium level:

  • >135=0
  • 135=2


Serum creatinine level:

  • 1.6mg/dl/141mmol/L = 0
  • >1.6mg/dl/141mmol/L = 2


Blood glucose level:

  • 180 mg/dL / 10 mmol/L=0
  • > 180 mg/dL / 10 mmol/L=1


A score greater than or equal to 6 indicates that necrotizing fasciitis should be seriously considered. It is worth noting, however, that the LRINEC score was derived from retrospective studies and has not been validated prospectively.[16]

MD calc has a helpful calculator for the test:

https://www.mdcalc.com/calc/1734/lrinec-score-necrotizing-soft-tissue-infection

Differential diagnosis

Management

Early recognition and initiation of high-dose antibiotics combined with tissue debridement is associated with lower mortality. Mild cases may respond to antibiotic therapy alone.[33] [34]

However, due to vascular thrombosis and destruction seen with fascial involvement, antibiotics generally have limited penetration. Therefore, antibiotic therapy has to be combined with prompt surgical debridement of the affected tissue. Standard antimicrobial therapy should consist of a combination of beta-lactam antibiotics, such as penicillin or cephalosporin and clindamycin. Benzyl penicillin is effective against GAS. The concurrent use of protein synthesis inhibiting antibiotic like clindamycin has a synergistic effect. It deters the production of streptococcal toxins and enzymes even at subinhibitory concentrations. Of note, polymicrobial type I periorbital necrotizing fasciitis may require the addition of aminoglycosides and/or metronidazole. [35]

The role of hyperbaric oxygen therapy in the management of NF is controversial. It may help to limit the ischemic tissue affected by NF. Intravenous gamma globulins are also recommended in the management of NF. Intravenous pooled immunoglobulins and heparinization help by neutralizing superantigen activity and aiding antibiotic perfusion.[19]

Medical follow up

A multi-disciplinary approach is usually warranted for patients with periorbital necrotizing fasciitis under the care of pediatricians, ENT surgeons, ophthalmologists and infectious disease specialists.

After the patient is stabilized through the acute phase, reconstructive surgery can be planned for a later date.

Surgery

Emergency surgical debridement is the primary management modality for periorbital NF. Debridement, necrosectomy and fasciotomy are the principle aspects of surgical intervention. [36]

Surgical management is indicated especially for patients displaying intense pain and skin color change, such as edema and/or ecchymoses, or signs of skin ischemia with blisters and bullae. Patients must be operated on emergently if they present with altered mental status, hypotension, left shift or metabolic acidosis.[36]

Early surgical intervention is life-saving and must be performed as early as possible, since a delay in treatment beyond 12 hours in fulminant forms of NF can prove fatal. Numerous studies have suggested that timing and the extent of the first debridement are the most important modifying factors in terms of increased mortality rate.[36]

Additionally, studies of other types of NF have also reported that the mortality rate was nine times greater when primary surgery was performed 24 hours after the onset of symptoms.[37]

Surgical debridement itself functions to decrease the bacterial load. Fortunately, good blood supply of the eyelids spares the lid margin from necrosis. It has been suggested that surgical debridement should involve mainly the subcutaneous tissue that harbors the infection without extensive skin resection involving the head and neck.[38]

Retention of the maximum amount of viable skin and orbicularis oculi permits faster healing, assists in antibiotic delivery and reduces facial disfigurement. Repeated debridement may be necessary if there is a slow therapeutic response.[8][38]

Complications

The possible complications are ominous and include optic neuropathy, retinal vein occlusion, severe exposure keratopathy, cavernous sinus thrombosis, meningitis and death.

Prognosis

Periorbital necrotizing fasciitis carries a mortality of 8.5 to 10% .[4][8]

Additional Resources

  • https://www.mdcalc.com/calc/1734/lrinec-score-necrotizing-soft-tissue-infection

References

  1. ↑ Kronish JW, McLeish WM. Eyelid necrosis and periorbital necrotizing fasciitis. Report of a case and review of the literature. Ophthalmology. 1991 Jan;98(1):92-8.
  2. ↑ Stone LA, Harshbarger RJ 3rdOrbital Necrotizing Fasciitis and Osteomyelitis Caused by Arcanobacterium Haemolyticum: A Case Report. Ophthal Plast Reconstr Surg. 2014 May 5.
  3. ↑ Lee S, Roh KH, Kim CK, Yong D, Choi JY, Lee JW, Lee K, Chong Y.A case of necrotizing fasciitis due to Streptococcus agalactiae, Arcanobacterium haemolyticum, and Finegoldia magna in a dog-bitten patient with diabetes. Korean J Lab Med. 2008 Jun;28(3):191-5.
  4. ↑ 4.0 4.1 4.2 Amrith S1, Hosdurga Pai V, Ling WW. Periorbital necrotizing fasciitis: a review. Acta Ophthalmol. 2013 Nov;91(7):596-603.
  5. ↑ Doorenbos-Bot AC, Hooymans JM, Blanksma LJ. Periorbital necrotising fasciitis due to Cryptococcus neoformans in a healthy young man. Doc Ophthalmol 1990;75: 315–20.
  6. ↑ Rath S1, Kar S, Sahu SK, Sharma S. Fungal periorbital necrotizing fasciitis in an immunocompetent adult. Ophthal Plast Reconstr Surg. 2009 Jul-Aug; 25(4):334-5.
  7. ↑ 7.0 7.1 Amrith S, Hosdurga Pai V, Ling WW. Periorbital necrotizing fasciitis -- a review. Acta Ophthalmol. 2013 Nov;91(7):596-603.
  8. ↑ 8.0 8.1 8.2 Lazzeri D, Lazzeri S, Figus M, Tascini C, Bocci G, Colizzi L, Giannotti G, Lorenzetti F, Gandini D, Danesi R, Menichetti F, Del Tacca M, Nardi M, Pantaloni M. Periorbital necrotising fasciitis. Br J Ophthalmol. 2010 Dec;94(12):1577-85.
  9. ↑ 9.0 9.1 9.2 Shindo ML, Nalbone VP, Dougherty WR. Necrotizing fasciitis of the face. Laryngoscope 1997;107:1071–9.
  10. ↑ 10.0 10.1 Elner VM, Demirci H, Nerad JA, et al. Periocular necrotizing fasciitis with visual loss. Pathogenesis and treatment. Ophthalmology 2006;113:2338–45.
  11. ↑ 11.0 11.1 Kronish JW, McLeish WM. Eyelid necrosis and periorbital necrotizing fasciitis. Report of a case and review of the literature, Ophthalmology 1991;98:92–8.
  12. ↑ 12.0 12.1 Luksich JA, Holds JB, Hartstein ME. Conservative management of necrotizing fasciitis of the eyelids. Ophthalmology 2002;109:2118–22.
  13. ↑ Gates RL, Cocke WM & Rushton TC(2001): Invasive streptococcal infection of the periorbita and forehead. Ann PlastSurg47: 565–567.
  14. ↑ Wong CH, Chang HC, Pasupathy S, Khin LW, Tan JL, Low CO. Necrotizing fasciitis: clinical presentation, microbiology, and determinants of mortality. J Bone Joint Surg Am. 2003;85-A 8:1454–1460.
  15. ↑ Wong CH, Wang YS. The diagnosis of necrotizing fasciitis. Curr Opin Infect Dis. 2005;18 2:101–106.
  16. ↑ 16.0 16.1 Wong CH. The LRINEC (Laboratory Risk Indicator for Necrotizing Fasciitis) score: a tool for distinguishing necrotizing fasciitis from other soft tissue infections. Crit Care Med. 2004;32:1535–1541.
  17. ↑ 17.0 17.1 Iwata Y, Sato S, Murase Y, et al. Five cases of necrotizing fasciitis: lack of skin inflammatory signs as a clinical clue for the fulminant type. J Dermatol. Nov 2008;35(11):719-25.
  18. ↑ K Tambe, A Tripathi, J Burns, and R Sampath. Multidisciplinary management of periocular necrotising fasciitis: a series of 11 patients. Eye (Lond). 2012 Mar; 26(3): 463–467.
  19. ↑ 19.0 19.1 Williams SR, Carruth JA, Brightwell AP.Necrotizing fasciitis of the face without significant trauma.Clin Otolaryngol Allied Sci. 1992 Aug;17(4):344-50.
  20. ↑ Bakleh M, Wold LE, Mandrekar JN, et al. Correlation of histopathologic findings with clinical outcome in necrotizing fasciitis. Clin Infect Dis 2005; 40:410–414
  21. ↑ 21.0 21.1 Struk DW, Munk PL, Lee MJ, Ho SG, Worsley DF. Imaging of soft tissue infections. Radiol Clin North Am 2001; 39:277–303
  22. ↑ 22.0 22.1 Struk DW, Munk PL, Lee MJ, Ho SG, Worsley DF. Imaging of soft tissue infections. Radiol Clin North Am 2001; 39:277–303
  23. ↑ 23.0 23.1 Becker M, Zbaren P, Hermans R, et al. Necrotizing fasciitis of the head and neck: role of CT in diagnosis and management. Radiology 1997; 202:471–476
  24. ↑ 24.0 24.1 Wysoki MG, Santora TA, Shah RM, Friedman AC. Necrotizing fasciitis: CT characteristics. Radiology 1997; 203:859–863
  25. ↑ 25.0 25.1 Zacharias N, Velmahos GC, Salama A, et al. Diagnosis of necrotizing soft tissue infections by computed tomography. Arch Surg 2010; 145:452–455
  26. ↑ 26.0 26.1 26.2 26.3 26.4 Turecki MB, Taljanovic MS, Stubbs AY, et al. Imaging of musculoskeletal soft tissue infections. Skeletal Radiol 2010; 39:957–971
  27. ↑ 27.0 27.1 Souyri C, Olivier P, Grolleau S, et al. Severe necrotizing soft-tissue infections and nonsteroidal anti-inflammatory drugs. Clin Exp Dermatol 2008; 33:249–255
  28. ↑ Brothers TE. Magnetic resonance imaging differences between necrotizing and nonnecrotizing fasciitis. J Am Coll Surg 1998; 187:416–421
  29. ↑ Wu CM, Davis F, Fishman EK. Musculoskeletal complications of the patient with acquired immunodeficiency syndrome (AIDS): CT evaluation. Semin Ultrasound CT MR 1998; 19:200–208
  30. ↑ Yu JS, Habib P. MR imaging of urgent inflammatory and infectious conditions affecting the soft tissues of the musculoskeletal system. Emerg Radiol 2009; 16:267–276
  31. ↑ Seok JH, Jee WH, Chun KA, et al. Necrotizing fasciitis versus pyomyositis: discrimination with using MR imaging. Korean J Radiol 2009; 10:121–128
  32. ↑ Drake DB, Woods JA, Bill TJ, et al. Magnetic resonance imaging in the early diagnosis of group A beta streptococcal necrotizing fasciitis; a case report. J Emerg Med 1998; 16:403–407
  33. ↑ Balaggan KS, Goolamali SI 2006: Periorbital necrotising fasciitis after minor trauma. Graefes Arch Clin Exp Ophthalmol 244: 268–270.
  34. ↑ Lee Hooi L, Hou BAC & Lay Leng S (2011): Group A Streptococcus necrotising fasciitis of the eyelid: a case report of good outcome with medical management. Ophthal Plast Reconstr Surg28: e13.
  35. ↑ Seal DV (2001): Necrotising fasciitis. Curr Opin Infect Dis14: 127–132.
  36. ↑ 36.0 36.1 36.2 Misiakos EP, Bagias G, Patapis P, Sotiropoulos D, Kanavidis P, Machairas A. Current concepts in the management of necrotizing fasciitis. Front Surg. 2014 Sep 29;1:36.
  37. ↑ Roje Z, Roje Z, Matic D, Librenjak D, Dokuzovic S, Varvodic J. Necrotizing fasciitis: literature review of contemporary strategies for diagnosing and management with three case reports: torso, abdominal wall, upper and lower limbs. Word J Emerg Surg (2011) 23(6):46.10.1186/1749-7922-6-46.
  38. ↑ 38.0 38.1 Saldana M, Gupta D, Khandwala M, Weir R, Beigi B. Periorbital necrotizing fasciitis: outcomes using a CT-guided surgical debridement approach. Eur J Ophthalmol. 2010 Jan-Feb;20(1):209-14.
  1. Kronish  JWMcLeish  WM Eyelid necrosis and periorbital necrotizing fasciitis: report of a case and review of the literature. Ophthalmology. 1991;9892- 98
  2. Stevens  DL Invasive group A streptococcus infections. Clin Infect Dis. 1992;142- 11
  3. Jain D, Kumar Y, Vasishta RK, et al. Zygomycotic necrotizing fasciitis in immunocompetent patients: a series of 18 cases. Mod Pathol 2006;19:1221– 6.
  4. Elner VM, Demirci H, Nerad JA, Hassan AS. Periocular necrotizing fasciitis with visual loss, pathogenesis and treatment. Ophthalmology. 2006;113:2338–2345.
  5. Schmid MR, Kossmann T, Duewell S. Differentiation of necrotising fasciitis and cellulitis using MR imaging. Am J Roentgenol. 1998;170:615–620.
  6. Arslan A, Pierre-Jerome C, Borthne A. Necrotising fasciitis: unreliable MRI findings in the preoperative diagnosis. Eur J Radiol. 2000;36:139–143.
  7. Chaudhry AA1, Baker KS, Gould ES, Gupta R. Necrotizing fasciitis and its mimics: what radiologists need to know. AJR Am J Roentgenol. 2015 Jan;204(1):128-39.

Complication:

  1. Kaul R, McGeer A, Low DE, Green K, Schwartz B. Population-based surveillance for Group A streptococcal necrotizing fasciitis: clinical features, prognostic indicators, and microbiologic analysis of seventy-seven cases. Ontario. Group A Streptococcal Study. Am J Med 1997;103:18-24.
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