Necrotizing Fasciitis: Clinical Presentation, Diagnostic Evaluation, Management, and Outcomes – A Case Report

Abstract

Necrotizing fasciitis (NF) is a rapidly progressive, life-threatening soft tissue infection characterized by widespread fascial necrosis, severe systemic toxicity, and high mortality if not promptly recognized and treated. The condition commonly affects the extremities, perineum, and trunk and is often associated with diabetes mellitus, immunosuppression, trauma, or recent surgery. Early diagnosis remains challenging because initial clinical findings may resemble cellulitis or other superficial soft tissue infections.

We present the case of a 58-year-old male with poorly controlled diabetes mellitus who presented with severe pain, swelling, erythema, and fever involving the left lower limb. Clinical examination, laboratory investigations, and imaging findings raised suspicion for necrotizing fasciitis. Emergency surgical debridement, broad-spectrum intravenous antibiotics, intensive supportive care, and wound management resulted in gradual clinical recovery.

This case highlights the importance of early recognition, aggressive surgical intervention, multidisciplinary management, and prompt antimicrobial therapy in improving outcomes among patients with necrotizing fasciitis.

Introduction

Necrotizing fasciitis is a severe soft tissue infection involving the fascia and subcutaneous tissues with rapid progression to tissue necrosis, systemic toxicity, septic shock, and multi-organ dysfunction. Despite advances in medical care, mortality rates remain between 20% and 40%, particularly when diagnosis and treatment are delayed.

The infection may be polymicrobial (Type I) or monomicrobial (Type II), most commonly involving Group A Streptococcus, Staphylococcus aureus, anaerobes, Enterobacterales, and other opportunistic pathogens.

Several factors increase susceptibility to necrotizing fasciitis, including:

• Diabetes mellitus
• Chronic kidney disease
• Immunosuppression
• Obesity
• Peripheral vascular disease
• Alcohol abuse
• Malignancy
• Recent trauma or surgery

Important pathological mechanisms include:

• Rapid bacterial proliferation
• Production of tissue-destroying toxins
• Microvascular thrombosis
• Fascial necrosis
• Impaired tissue perfusion
• Systemic inflammatory response

Common clinical manifestations include:

• Severe pain disproportionate to physical findings
• Rapidly spreading erythema
• Swelling and edema
• Fever and chills
• Skin discoloration
• Bullae formation
• Crepitus
• Signs of sepsis

Early recognition and emergency surgical management are essential to reduce morbidity and mortality.

Case Report

Patient History

A 58-year-old male presented to the emergency department with:

• Severe pain in the left lower leg for 3 days
• Progressive swelling
• Redness of the affected limb
• High-grade fever with chills
• Difficulty walking
• Generalized weakness

The patient reported sustaining a minor abrasion to the lower leg one week prior while working outdoors. Initially, the wound appeared insignificant but progressively worsened.

Past medical history revealed:

• Type 2 diabetes mellitus for 12 years
• Hypertension
• Poor glycemic control

There was no history of:

• Recent surgery
• Deep vein thrombosis
• Autoimmune disease
• Malignancy
• Immunosuppressive therapy

Clinical Examination

General Examination

• Temperature: 39.2°C
• Pulse rate: 118/min
• Blood pressure: 96/62 mmHg
• Respiratory rate: 24/min
• Oxygen saturation: 95% on room air

The patient appeared toxic and dehydrated.

Local Examination

Examination of the left lower limb revealed:

• Diffuse swelling extending from ankle to knee
• Marked erythema
• Skin warmth
• Extreme tenderness
• Areas of dusky skin discoloration
• Multiple hemorrhagic bullae
• Foul-smelling serous discharge

Pain was disproportionately severe compared to visible skin findings.

Palpation demonstrated:

• Subcutaneous edema
• Areas of skin anesthesia
• Crepitus suggestive of gas-forming infection

Clinical Evaluation

Differential Diagnosis

The following conditions were considered:

• Severe cellulitis
• Deep vein thrombosis
• Gas gangrene
• Pyomyositis
• Necrotizing fasciitis

The rapid progression, severe pain, systemic toxicity, skin discoloration, and crepitus strongly suggested necrotizing fasciitis.

Investigations

Laboratory Findings

• White blood cell count: 24,500/mm³
• C-reactive protein: Markedly elevated
• Serum sodium: 130 mmol/L
• Serum creatinine: Elevated
• Random blood glucose: 312 mg/dL
• HbA1c: 9.8%
• Serum lactate: Elevated

Blood cultures were obtained before initiation of antibiotic therapy.

Imaging

Plain Radiography

• Presence of soft tissue gas within fascial planes

Contrast-Enhanced CT Scan

Findings included:

• Fascial thickening
• Extensive soft tissue edema
• Gas tracking along fascial planes
• Subcutaneous air pockets

These findings strongly supported the diagnosis of necrotizing fasciitis.

Microbiology

Tissue samples obtained during surgery demonstrated:

• Gram-positive cocci
• Mixed aerobic and anaerobic organisms

Culture later confirmed polymicrobial infection involving:

• Streptococcus pyogenes
• Escherichia coli
• Bacteroides species

Diagnosis

Based on clinical findings, laboratory abnormalities, imaging studies, and operative findings, a diagnosis of Acute Polymicrobial Necrotizing Fasciitis of the Left Lower Limb was established.

Management and Outcome

Initial Management

The patient was immediately admitted to the intensive care unit.

Resuscitative measures included:

• Intravenous fluid therapy
• Hemodynamic monitoring
• Glycemic control using insulin infusion
• Electrolyte correction

Broad-spectrum empirical antimicrobial therapy was initiated with:

• Piperacillin-tazobactam
• Clindamycin
• Vancomycin

Surgical Management

Emergency surgical exploration was performed within hours of diagnosis.

Intraoperative findings included:

• Extensive fascial necrosis
• Gray, nonviable tissue
• Thin foul-smelling exudate
• Easy separation of fascial planes

Aggressive surgical debridement was undertaken to remove all necrotic tissue.

The patient subsequently underwent two additional debridement procedures over the next week to ensure complete source control.

Follow-Up and Clinical Course

At 72 Hours

• Reduction in fever
• Improved hemodynamic stability
• Declining inflammatory markers

At 1 Week

• Healthy granulation tissue formation
• No further progression of infection
• Improved glycemic control

At 3 Weeks

• Wound bed suitable for reconstruction
• Split-thickness skin grafting performed

At 2 Months

• Complete wound healing
• Restoration of limb function
• No evidence of recurrent infection

The patient continued outpatient follow-up with surgical and diabetic care teams.

Discussion

Pathophysiology

Necrotizing fasciitis involves rapid destruction of fascia and subcutaneous tissues resulting from bacterial invasion and toxin production.

Key pathological processes include:

• Tissue ischemia
• Microvascular thrombosis
• Cytokine-mediated inflammation
• Fascial necrosis
• Systemic inflammatory response syndrome

Bacterial toxins contribute significantly to tissue destruction and systemic toxicity.

Epidemiology

Important epidemiological features include:

• Rare but highly fatal infection
• Incidence increasing worldwide
• More common in diabetic patients
• Higher prevalence among immunocompromised individuals
• Significant healthcare burden due to prolonged hospitalization

Clinical Manifestations

Common symptoms include:

• Severe pain
• Fever
• Swelling
• Rapid progression of skin changes

Characteristic signs include:

• Skin discoloration
• Bullae formation
• Crepitus
• Tissue necrosis
• Septic shock

Pain out of proportion to examination findings remains one of the earliest and most important clinical clues.

Diagnostic Considerations

Diagnosis is primarily clinical and should not be delayed while awaiting confirmatory investigations.

Useful diagnostic modalities include:

1. Laboratory evaluation
2. LRINEC scoring system
3. Plain radiography
4. Computed tomography
5. Magnetic resonance imaging
6. Surgical exploration

Surgical exploration remains the gold standard for definitive diagnosis.

Treatment Modalities

Surgical Therapy

The cornerstone of treatment includes:

• Immediate surgical exploration
• Aggressive debridement
• Repeat debridement when required

Delayed surgery significantly increases mortality.

Antimicrobial Therapy

Recommended broad-spectrum coverage should target:

• Streptococci
• Staphylococci
• Gram-negative organisms
• Anaerobic bacteria

Clindamycin is often added because of its toxin-suppressing effects.

Supportive Care

Supportive measures include:

• Intensive care monitoring
• Fluid resuscitation
• Vasopressor support when necessary
• Glycemic control
• Nutritional support

Complications

Potential complications include:

• Septic shock
• Multi-organ failure
• Limb loss
• Acute kidney injury
• Respiratory failure
• Prolonged hospitalization
• Death

Early intervention substantially reduces these risks.

Prognosis

The prognosis depends upon:

• Time to diagnosis
• Early surgical intervention
• Adequacy of debridement
• Presence of comorbidities
• Severity of sepsis

Patients receiving prompt surgical and medical management have significantly improved survival outcomes.

Conclusion

Necrotizing fasciitis is a rapidly progressive surgical emergency associated with significant morbidity and mortality. Early recognition of severe pain, rapidly spreading soft tissue infection, systemic toxicity, and characteristic skin findings is essential for timely diagnosis.

This case emphasizes the critical importance of prompt surgical debridement, broad-spectrum antimicrobial therapy, intensive supportive care, and multidisciplinary management in achieving favorable clinical outcomes. Early intervention remains the most important factor influencing survival and long-term functional recovery.

References

1. Stevens DL, Bryant AE. Necrotizing Soft-Tissue Infections. https://pubmed.ncbi.nlm.nih.gov/29236909/
2. Wong CH, Khin LW, Heng KS, Tan KC, Low CO. The LRINEC Score. https://pubmed.ncbi.nlm.nih.gov/15241098/
3. Goh T, Goh LG, Ang CH, Wong CH. Early diagnosis of necrotizing fasciitis. https://pubmed.ncbi.nlm.nih.gov/22179937/
4. Sartelli M, Guirao X, Hardcastle TC, et al. Management of skin and soft tissue infections. https://pubmed.ncbi.nlm.nih.gov/30737049/
5. Centers for Disease Control and Prevention. Necrotizing Fasciitis. https://www.cdc.gov/group-a-strep/about/necrotizing-fasciitis.html
6. World Health Organization. Sepsis and severe infections. https://www.who.int

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