Ecthyma gangrenosum is a cutaneous manifestation of Pseudomonas aeruginosa septicemia occurring in an immunocompromised or neutropenic patient. A toxic appearance with fever, abnormal vital signs, and altered consciousness is common. The initially erythematous macules develop bullae or pustules surrounded by violaceous halos. Bullae become hemorrhagic and rupture (pustules breakdown), becoming necrotic ulcers with central black or gray eschars. The time course from macule to eschar can occur within 12 to 24 hours. The lesions primarily affect the anogenital areas (> 50%) but may appear anywhere on the body. Ecthyma gangrenosum is seen in up to 13% of patients with P aeruginosa septicemia and rarely in nonbacteremic patients. Other bacteria causing septicemia (Aeromonas hydrophila, Aspergillus, Burkholderia cepacia, Candida, Citrobacter freundii, Escherichia coli, Fusarium, Pseudomonas stutzeri) may present with similar ecthyma gangrenosum–like lesions.
Management and Disposition
Ecthyma gangrenosum is associated with life-threatening P aeruginosa sepsis and a high mortality. Appropriate supportive care measures and rapid initiation of antipseudomonal antibiotics are required; delaying antibiotics can increase mortality. Dermatology consultation for diagnosis confirmation and infectious disease for antibiotic guidance can be helpful. Patients with oncologists should consult the oncology service and follow oncology protocols.
Patients with ecthyma gangrenosum are severely immunosuppressed, and many other bacteria and fungi can cause similar lesions.
Without examining the entire patient, these lesions can be completely missed.
Multiple lesions, delayed diagnosis, and delayed institution of appropriate antibiotics portend a poor prognosis.
Ecthyma Gangrenosum. A typical hemorrhagic bulla of ecthyma gangrenosum secondary to pseudomonal sepsis. (Photo contributor: James Mensching, DO.)
Pseudomonas aeruginosa Infected Ulcerations. Note the green colored crusting. (Photo contributor: J. Matthew Hardin, MD.)