Ecthyma gangrenosum of the scrotum: a case report

Abstract

A 43-year-old man with pancytopenia from chemotherapy for acute myeloid leukemia developed left scrotal pain, fever, and rigors. Physical exam revealed an ulcerating lesion with central necrosis and eschar surrounded by a halo of erythema on the inferior aspect of the left scrotum. The condition indicated an early necrotizing soft tissue infection. The patient was started on broad-spectrum antibiotics and taken to the operating room for a wound debridement. Blood and tissue cultures grew Pseudomonas aeruginosa, which confirmed the diagnosis of ecthyma gangrenosum of the scrotum. The fever resolved, and the wound healed without further progression after wet to dry dressing changes.

Keywords

ecthyma gangrenosum / scrotum / genitalia

Introduction

Ecthyma gangrenosum (EG) is an uncommon skin lesion first described by Barker in 1897. However, the term only became widely accepted in the 1950s [ 1]. This condition was postulated to be a pathognomonic of Pseudomonas aeruginosa septicemia that typically affects immunocompromised patients, particularly those receiving immune modulating agents for malignant diseases [ 2]. It can affect patients of any age, but it is usually observed in infants and elderly patients because of their underdeveloped or compromised immune systems. EG may affect both genders, although observational studies have found that males have a slight predisposition to EG in comparison with females [ 2].

Case report

A 43-year-old man with acute myeloid leukemia was receiving chemotherapy. He spontaneously started complaining of acute pain in the left scrotum, scrotal swelling, and fever with rigors. A physical exam revealed an ulcerating lesion with central necrosis and eschar surrounded by a halo of erythema on the inferior aspect of the left scrotum (Figs. 1 and 2). Further observations revealed minimal drainage from the wound and no lymphadenopathy. The testicles were palpable bilaterally, and a stat scrotal ultrasound showed no underlying fluid collection or testicular/cord involvement. The patient had been pancytopenic because of his treatment for leukemia. He was started on broad-spectrum antibiotics and taken to the operating room for a wound exploration and debridement. Postoperatively, his pain improved, and his fever resolved. Blood and tissue cultures grew P. aeruginosa, which confirmed a diagnosis of EG of the scrotum.

Discussion

EG is pathognomonic for superficial soft tissue infection that typically affects immunocompromised patients with bacteremia caused by P. aeruginosa. A review of 167 bacteremic patients with EG found P. aeruginosa in 73.65% of blood cultures. Occasionally, Escherichia coli, Klebsiella pneumonia, Morganella morganii and fungi bacteremia can cause EG [ 3, 4].

EG has also been observed in previously healthy children. However, these patients subsequently developed immune deficits [ 5]. Other risk factors associated with EG include diabetes, malnutrition, children with intra-abdominal or appendiceal abscesses, recent viral illnesses, hypogammaglobulinemia, and neutropenia [ 6]. The mortality rates of Pseudomonas sepsis in immunocompromised patients range from 18% to 96%, whereas the mortality rate of EG in non-bacteremic patients is 15.4% [ 2– 5].

The lesions of EG typically present as a painless red macule that rapidly evolves into an area of induration; this macule in turn develops into pustules and/or bullae that subsequently progress to develop gangrenous ulcers within 12 to 18 hours [ 7]. This progression is attributed to bacterial invasion of the media and the adventitia of arteries and veins, causing thrombosis of venules and arterioles, which leads to tissue edema and separation of the epidermis. This causes an erythematous macule to form, which eventually evolves into a necrotic ulcer with eschar.

A diagnosis of EG is a clinical diagnosis based of the clinical appearance of the characteristic lesions. Clinicians must remain vigilant because EG can affect any skin surface of the body. Blood and exudate cultures may also identify the causative pathogen. However, the presence of these lesions is indicative of the possibility of bacteremia, particularly bacteremia caused by P. aeruginosa. Pseudomonas septicemia carries a mortality rate ranging from 16% to 90% [ 8].

The differential diagnoses for necrotizing soft tissue infection of the scrotum include cellulitis, scrotal abscess, streptococcal necrotizing fasciitis, vascular occlusion syndromes, pyoderma gangrenosum, allergic vasculitis, Fournier’s gangrene, warfarin necrosis, and necrolytic migratory erythema. Other diseases associated with EG include Shanghai fever, which is a community-acquired enteric illness associated with sepsis caused by Pseudomonas. More than 50% of patients with Shanghai fever develop EG [ 9].

EG treatment involves a broad-spectrum antibiotic (piperazolin-tazobactam, cefepime, gentamicin, levofloxacin) that covers for Pseudomonas, followed by the surgical debridement of the necrotic tissue. Antibiotics can be narrowed once sensitivities from the wound culture return. Immediate source control is imperative, and clinicians should not delay treatment pending the results of cultures. In our case, the patient was placed on broad-spectrum antibiotics and underwent an immediate surgical debridement of the wound prior to the return of the blood and wound cultures. The patient tolerated the procedure well and underwent a full recovery. Follow-up after one month revealed a uniformly healed surgical scar.

Conclusions

Clinicians should be aware of the characteristics of EG because it is a pathognomonic of bacteremia, typically related to P. aeruginosa. Recognizing this skin lesion should prompt the initiation of broad-spectrum antibiotics and immediate surgical excision of the lesion prior to the results of blood cultures. This is the first reported case of EG of the scrotum in the English literature.

References

[1] Barker LF. The clinical symptoms, bacteriologic findings and postmortem appearances in cases of infection of human beings with the Bacillus pyocyaneus. JAMA 1897; 29(5): 213–216

[2] Vaiman M, Lazarovitch T, Heller L, Lotan G. Ecthyma gangrenosum and ecthyma-like lesions: review article. Eur J Clin Microbiol Infect Dis 2015; 34(4): 633–639

[3] Soria A, Francès C, Guihot A, Varnous S, Bricaire F, Caumes E. Etiology of ecthyma gangrenosum: four cases. Ann Dermatol Venereol 2010; 137(6-7): 472–476 (in French)

[4] Edelstein H, Cutting HO. Escherichia coli as cause of ecthyma gangrenosum. Postgrad Med 1986; 79(2): 44–45

[5] Zomorrodi A, Wald ER. Ecthyma gangrenosum: considerations in a previously healthy child. Pediatr Infect Dis J 2002; 21(12): 1161–1164

[6] Koo SH, Lee JH, Shin H, Lee JI. Ecthyma gangrenosum in a previously healthy infant. Arch Plast Surg 2012; 39(6): 673–675

[7] Kanj S, Sexton D. Pseudomonas aeruginosa skin, soft tissue and bone infections. UpToDate, Waltham, MA. (Accessed on<Date> September 30</Date> 2015)

[8] Maschmeyer G, Braveny I. Review of the incidence and prognosis of Pseudomonas aeruginosa infections in cancer patients in the 1990s. Eur J Clin Microbiol Infect Dis 2000; 19(12): 915–925

[9] Chuang CH, Wang YH, Chang HJ, Chen HL, Huang YC, Lin TY, Ozer EA, Allen JP, Hauser AR, Chiu CH. Shanghai fever: a distinct Pseudomonas aeruginosa enteric disease. Gut 2014; 63(5): 736–743

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