eMedicine Specialties > Dermatology > Bacterial Infections

Necrotizing Fasciitis: Differential Diagnoses & Workup

Author: Robert A Schwartz, MD, MPH, Professor and Head, Dermatology, Professor of Pathology, Pediatrics, Medicine, and Preventive Medicine and Community Health, UMDNJ-New Jersey Medical School
Coauthor(s): Rajendra Kapila, MD, MBBS, Professor of Medicine, Department of Medicine, UMDNJ, New Jersey Medical School
Contributor Information and Disclosures

Updated: May 5, 2009

Differential Diagnoses

Acute Febrile Neutrophilic Dermatosis
Acute Hemorrhagic Edema of Infancy
Cellulitis
Erythema Induratum (Nodular Vasculitis)

Workup

Laboratory Studies

  • Examination by an experienced surgeon is critical. Necrotizing fasciitis may be associated with a WBC count more than 14,000/µL, a serum sodium less than 135 mmol/L, and a blood urea nitrogen level greater than 15 mg/dL; however, these parameters cannot be relied upon in a clinical setting.
  • Laboratory tests, along with appropriate imaging studies, may facilitate the diagnosis of necrotizing fasciitis.20
  • Although the laboratory parameters may vary in a given clinical setting, the following may be associated with necrotizing fasciitis:
    • The WBC count may be elevated. It may be more than 14,000/µL.
    • The blood urea nitrogen level may be elevated. It may be greater than 15 mg/mL.
    • The serum sodium level may be reduced. The level may be less than 135 mmol/L.
  • New techniques include rapid streptococcal diagnostic kits and a polymerase chain reaction (PCR) involving SPE genes (eg, SPE-B).

Imaging Studies

  • Standard radiographs are of little value unless free air is depicted, as with gas-forming infections.
  • Some authors believe CT scanning may be more sensitive than plain radiography in demonstrating subcutaneous air.
  • B-mode and possibly color Doppler ultrasonography, contrast-enhanced CT scanning, and the appropriate laboratory tests, may facilitate the rapid diagnosis of necrotizing fasciitis.
  • T2-weighted MRI may show well-defined regions of high signal intensity in the deep tissues.
  • More importantly, MRI or CT scan delineation of the extent of necrotizing fasciitis may be useful in directing rapid surgical debridement.
  • MRI can be used to identify necrotizing fasciitis, but its sensitivity exceeds its specificity.21
  • Bedside ultrasonography may be useful in patients with soft tissue infections, including cellulitis, cutaneous abscess, peritonsillar abscess, and necrotizing fasciitis. It may be superior to clinical judgment alone in determining the presence or the absence of occult abscess formation.22

Other Tests

  • Excisional deep skin biopsy may be helpful in diagnosing and identifying the causative organisms.
  • Cultures of the affected tissue obtained at initial debridement may be helpful.
  • Gram staining of the exudate may provide a clue as to whether a type I or type II infection is present; the type influences the antibiotic therapy.

Histologic Findings

Sections show superficial fascial necrosis with blood vessels occluded by thrombi. A dense infiltration of neutrophils may be observed in deeper parts of the subcutaneous tissue and fascia. Subcutaneous fat necrosis and vasculitis are also evident. Eccrine glands and ducts may be necrotic. Alcian blue or periodic acid-Schiff staining with diastase may show clusters of bacteria and fungi. Excisional deep skin biopsy may be helpful in diagnosing and identifying the causative organisms.23

More on Necrotizing Fasciitis

Overview: Necrotizing Fasciitis
Differential Diagnoses & Workup: Necrotizing Fasciitis
Treatment & Medication: Necrotizing Fasciitis
Follow-up: Necrotizing Fasciitis
Multimedia: Necrotizing Fasciitis
References
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References

  1. Kihiczak GG, Schwartz RA, Kapila R. Necrotizing fasciitis: a deadly infection. J Eur Acad Dermatol Venereol. Apr 2006;20(4):365-9. [Medline].

  2. Federman DG, Kravetz JD, Kirsner RS. Necrotizing fasciitis and cardiac catheterization. Cutis. Jan 2004;73(1):49-52. [Medline].

  3. Akcay EK, Cagil N, Yulek F, et al. Necrotizing fasciitis of eyelid secondary to parotitis. Eur J Ophthalmol. Jan-Feb 2008;18(1):128-30. [Medline].

  4. Anwar UM, Ahmad M, Sharpe DT. Necrotizing Fasciitis After Liposculpture. Aesthetic Plast Surg. 12 2 2004;[Medline].

  5. Bisno AL, Cockerill FR 3rd, Bermudez CT. The initial outpatient-physician encounter in group A streptococcal necrotizing fasciitis. Clin Infect Dis. Aug 2000;31(2):607-8. [Medline].

  6. Gibbon KL, Bewley AP. Acquired streptococcal necrotizing fasciitis following excision of malignant melanoma. Br J Dermatol. Oct 1999;141(4):717-9. [Medline].

  7. Sewell GS, Hsu VP, Jones SR. Zoster gangrenosum: necrotizing fasciitis as a complication of herpes zoster. Am J Med. Apr 15 2000;108(6):520-1. [Medline].

  8. Tung-Yiu W, Jehn-Shyun H, Ching-Hung C, Hung-An C. Cervical necrotizing fasciitis of odontogenic origin: a report of 11 cases. J Oral Maxillofac Surg. Dec 2000;58(12):1347-52; discussion 1353. [Medline].

  9. Morgan WR, Caldwell MD, Brady JM. Necrotizing fasciitis due to a methicillin-sensitive Staphylococcus aureus isolate harboring an enterotoxin gene cluster. J Clin Microbiol. Feb 2007;45(2):668-71. [Medline].

  10. Cheng NC, Chang SC, Kuo YS, Wang JL, Tang YB. Necrotizing fasciitis caused by methicillin-resistant Staphylococcus aureus resulting in death. A report of three cases. J Bone Joint Surg Am. May 2006;88(5):1107-10. [Medline].

  11. Fustes-Morales A, Gutierrez-Castrellon P, Duran-Mckinster C, Orozco-Covarrubias L, Tamayo-Sanchez L, Ruiz-Maldonado R. Necrotizing fasciitis: report of 39 pediatric cases. Arch Dermatol. Jul 2002;138(7):893-9. [Medline].

  12. Ford LM, Waksman J. Necrotizing fasciitis during primary varicella. Pediatrics. Jun 2000;105(6):1372-3; discussion 1373-5. [Medline].

  13. Dahm P, Roland FH, Vaslef SN, et al. Outcome analysis in patients with primary necrotizing fasciitis of the male genitalia. Urology. Jul 2000;56(1):31-5; discussion 35-6. [Medline].

  14. 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. [Medline].

  15. Zahar JR, Goveia J, Lesprit P, Brun-Buisson C. Severe soft tissue infections of the extremities in patients admitted to an intensive care unit. Clin Microbiol Infect. Jan 2005;11(1):79-82. [Medline].

  16. Tang WM, Ho PL, Yau WP, Wong JW, Yip DK. Report of 2 fatal cases of adult necrotizing fasciitis and toxic shock syndrome caused by Streptococcus agalactiae. Clin Infect Dis. Oct 2000;31(4):E15-7. [Medline].

  17. Sendi P, Johansson L, Dahesh S, et al. Bacterial phenotype variants in group B streptococcal toxic shock syndrome. Emerg Infect Dis. Feb 2009;15(2):223-32. [Medline].

  18. Dawar M, Russell B, McClean K, Levett PN, Tyrrell GJ, Irvine J. A case of necrotizing fasciitis due to Streptococcus pneumoniae serotype 5 in Saskatchewan. Can J Infect Dis Med Microbiol. Jan 2008;19(1):69-71. [Medline].

  19. Tang WM, Fung KK, Cheng VC, Lucke L. Rapidly progressive necrotising fasciitis following a stonefish sting: a report of two cases. J Orthop Surg (Hong Kong). Apr 2006;14(1):67-70. [Medline].

  20. Simonart T, Simonart JM, Derdelinckx I, et al. Value of standard laboratory tests for the early recognition of group A beta-hemolytic streptococcal necrotizing fasciitis. Clin Infect Dis. Jan 2001;32(1):E9-12. [Medline].

  21. Arslan A, Pierre-Jerome C, Borthne A. Necrotizing fasciitis: unreliable MRI findings in the preoperative diagnosis. Eur J Radiol. Dec 2000;36(3):139-43. [Medline].

  22. Ramirez-Schrempp D, Dorfman DH, Baker WE, Liteplo AS. Ultrasound soft tissue applications in the pediatric emergency department: to drain or not to drain?. Pediatr Emerg Care. Jan 2009;25(1):44-8. [Medline].

  23. Bakleh M, Wold LE, Mandrekar JN, Harmsen WS, Dimashkieh HH, Baddour LM. Correlation of histopathologic findings with clinical outcome in necrotizing fasciitis. Clin Infect Dis. Feb 1 2005;40(3):410-4. [Medline].

  24. Korhonen K. Hyperbaric oxygen therapy in acute necrotizing infections with a special reference to the effects on tissue gas tensions. Ann Chir Gynaecol Suppl. 2000;(214):7-36. [Medline].

  25. Korhonen K, Kuttila K, Niinikoski J. Tissue gas tensions in patients with necrotising fasciitis and healthy controls during treatment with hyperbaric oxygen: a clinical study. Eur J Surg. Jul 2000;166(7):530-4. [Medline].

  26. Krenk L, Nielsen HU, Christensen ME. Necrotizing fasciitis in the head and neck region: an analysis of standard treatment effectiveness. Eur Arch Otorhinolaryngol. Mar 6 2007;[Medline].

  27. Hsiao CT, Weng HH, Yuan YD, Chen CT, Chen IC. Predictors of mortality in patients with necrotizing fasciitis. Am J Emerg Med. Feb 2008;26(2):170-5. [Medline].

  28. Afifi RY, El-Hindawi AA. Acute necrotizing fasciitis in Egyptian patients. Int J Surg. Jan 28 2008;[Medline].

  29. Brandt MM, Corpron CA, Wahl WL. Necrotizing soft tissue infections: a surgical disease. Am Surg. Oct 2000;66(10):967-70; discussion 970-1. [Medline].

  30. Chan HT, Low J, Wilson L, Harris OC, Cheng AC, Athan E. Case cluster of necrotizing fasciitis and cellulitis associated with vein sclerotherapy. Emerg Infect Dis. Jan 2008;14(1):180-1. [Medline].

  31. Cox NH. Streptococcal necrotizing fasciitis and the dermatologist. Br J Dermatol. Oct 1999;141(4):613-4. [Medline].

  32. Elliott D, Kufera JA, Myers RA. The microbiology of necrotizing soft tissue infections. Am J Surg. May 2000;179(5):361-6. [Medline].

  33. Hassell M, Fagan P, Carson P, Currie BJ. Streptococcal necrotising fasciitis from diverse strains of Streptococcus pyogenes in tropical northern Australia: case series and comparison with the literature. BMC Infect Dis. Dec 16 2004;4(1):60. [Medline].

  34. Hsieh T, Samson LM, Jabbour M, Osmond MH. Necrotizing fasciitis in children in eastern Ontario: a case-control study. CMAJ. Aug 22 2000;163(4):393-6. [Medline].

  35. Urschel JD. Necrotizing soft tissue infections. Postgrad Med J. Nov 1999;75(889):645-9. [Medline].

  36. Wall DB, de Virgilio C, Black S, Klein SR. Objective criteria may assist in distinguishing necrotizing fasciitis from nonnecrotizing soft tissue infection. Am J Surg. Jan 2000;179(1):17-21. [Medline].

  37. Wall DB, Klein SR, Black S, de Virgilio C. A simple model to help distinguish necrotizing fasciitis from nonnecrotizing soft tissue infection. J Am Coll Surg. Sep 2000;191(3):227-31. [Medline].

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Further Reading

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Contributor Information and Disclosures

Author

Robert A Schwartz, MD, MPH, Professor and Head, Dermatology, Professor of Pathology, Pediatrics, Medicine, and Preventive Medicine and Community Health, UMDNJ-New Jersey Medical School
Robert A Schwartz, MD, MPH is a member of the following medical societies: Alpha Omega Alpha, American Academy of Dermatology, American College of Physicians, and Sigma Xi
Disclosure: Nothing to disclose.

Coauthor(s)

Rajendra Kapila, MD, MBBS, Professor of Medicine, Department of Medicine, UMDNJ, New Jersey Medical School
Rajendra Kapila, MD, MBBS is a member of the following medical societies: American College of Physicians, American Medical Association, Infectious Diseases Society of America, and Infectious Diseases Society of New Jersey
Disclosure: Nothing to disclose.

Medical Editor

Janet Fairley, MD, Professor and Head, Department of Dermatology, University of Iowa
Janet Fairley, MD is a member of the following medical societies: American Academy of Dermatology, American Dermatological Association, American Federation for Medical Research, and Society for Investigative Dermatology
Disclosure: Nothing to disclose.

Pharmacy Editor

Michael J Wells, MD, Associate Professor, Department of Dermatology, Texas Tech University Health Sciences Center
Michael J Wells, MD is a member of the following medical societies: Alpha Omega Alpha, American Academy of Dermatology, American Medical Association, and Texas Medical Association
Disclosure: Nothing to disclose.

Managing Editor

Van Perry, MD, Assistant Professor, Department of Medicine, Division of Dermatology, University of Texas Health Science Center
Van Perry, MD is a member of the following medical societies: American Academy of Dermatology and American Society for Laser Medicine and Surgery
Disclosure: Nothing to disclose.

CME Editor

Glen H Crawford, MD, Assistant Clinical Professor, Department of Dermatology, University of Pennsylvania School of Medicine; Chief, Division of Dermatology, The Pennsylvania Hospital
Glen H Crawford, MD is a member of the following medical societies: Alpha Omega Alpha, American Academy of Dermatology, American Medical Association, Phi Beta Kappa, and Society of USAF Flight Surgeons
Disclosure: Nothing to disclose.

Chief Editor

Dirk M Elston, MD, Director, Department of Dermatology, Geisinger Medical Center
Dirk M Elston, MD is a member of the following medical societies: American Academy of Dermatology
Disclosure: Nothing to disclose.

 
 
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