Necrotic cellulitis. A localized form of septic vasculitis

Area of Science:

• Dermatopathology
• Infectious Disease Pathology

Background:

• Necrotic cellulitis is a severe skin infection.
• Bacterial septicemia involves bacteria in the bloodstream.
• Distinguishing localized vs. systemic bacterial infections can be challenging.

Observation:

• Cutaneous biopsies from two patients with necrotic cellulitis revealed neutrophilic vasculitis and fibrin thrombi.
• These microscopic findings were identical to those in a patient with bacterial septicemia.

Findings:

• The histopathological changes in localized bacterial necrotic cellulitis are indistinguishable from those in bacterial septicemia.
• Neutrophilic vasculitis with fibrin thrombi is a key shared feature.

Implications:

• Definitive diagnosis of localized or systemic septic vasculitis requires integrating clinical information with biopsy findings.
• This highlights the importance of correlating histopathology with patient presentation in diagnosing severe bacterial infections.