Extensive Refractory Perineal Pyoderma Gangrenosum Treated with Infliximab, Fecal Diversion, and Negative-Pressure Wound Therapy

Pyoderma gangrenosum (PG) is a rare ulcerating skin disease often associated with inflammatory bowel disease (IBD), with an estimated incidence of 3–10 cases per million population per year [1, 2]. The etiology of PG is poorly understood but probably involves an interplay of genetic and environmental factors with loss of innate immune regulation and altered neutrophil chemotaxis [2, 3]. Diagnosis is challenging since this condition can exhibit different clinical presentations (namely in morphology and affected sites), may overlap with other conditions, and is associated with several systemic diseases [1, 4].

Recently a group of international experts defined criteria for its diagnosis – the Delphi criteria – yielding a sensitivity and specificity of 86 and 90%, respectively. They include 1 major criterion (biopsy with neutrophilic infiltrate) and 8 minor criteria (exclusion of infection on histology; pathergy; personal history of IBD or inflammatory arthritis; papule, pustule or vesicle that rapidly ulcerates; peripheral erythema, undetermined borders, and tenderness at the site of ulceration; multiple ulcerations [at least one occurring on an anterior lower leg]; cribriform or wrinkled paper scars at healed ulcer sites; and a decrease in ulcer size after immunosuppressive treatment) [4].

We report a case of a 57-year-old female patient receiving 5-ASA who was diagnosed with ulcerative colitis (UC) 8 years ago. She was admitted to the emergency department due to the appearance of a profound ulcer on the inside of the thigh, extending from the left large vaginal lip to the perianal area (Fig. 1a) and a rapidly progressive painful ulcer in the right foot with peripheral erythema and undetermined borders (Fig. 2a). She had two bowel movements/day with blood in the stool, and sigmoidoscopy showed lesions compatible with Mayo 3 UC.

Biopsy of the lesion from the foot was obtained, showing neutrophilic infiltration compatible with PG. Infections were excluded by serology and skin biopsy. The patient performed a pelvic computed tomography scan that showed a perianal collection lateralized to the left with extension to the vulva with fistulization of the large left vulvar lip and the possibility of rectal fistulization.

Based on the diagnosis of PG, the patient was started on corticosteroids (oral prednisolone 1 mg/kg/day followed by endovenous hydrocortisone 400 mg/day) with no significant clinical improvement. Taking into account the extent of the perineal lesions and after multidisciplinary consultation (gastroenterology, dermatology, and surgery) it was decided to initiate infliximab 5 mg/kg and to perform derivation ileostomy and negative-pressure wound therapy (NPWT). There was marked improvement of the lesions, and the patient was discharged after 2 months. At 4 months, there was almost complete resolution of the lesions (Fig. 1b, 2b).

Considering the excellent evolution of the lesion with complete healing and also the healing of the colonic mucosa on follow-up colonoscopy, the patient was proposed for reconstruction of the intestinal transit, which was uneventful.

PG algorithm treatment is controversial and remains poorly characterized due to limited knowledge of its pathophysiology combined with its rarity [1, 2, 5].

It is generally based on wound care, analgesia, topical or intralesional therapy with corticosteroids, and systemic therapy with corticosteroids, cyclosporine, or anti-TNF agents. A randomized, placebo-controlled study found that infliximab had a beneficial clinical response in 69% of the patients and a remission rate of 21% at week 6 [6]. A systematic review with 60 cases found that 92% of the patients had response to anti-TNF [5].

The role of surgical treatment in PG is controversial as 25–50% of the PG lesions demonstrate pathergy and theoretically could worsen with surgical intervention [3].

Nevertheless, NPWT has demonstrated efficacy in the treatment of chronic wounds in a variety of circumstances. The rational of the use of subatmospheric pressure therapy includes increased tissue perfusion, control of the advancing ischemic process, production of a healthy granular wound bed, reduced bacterial load, and pain relief. Some reports show its safety and efficacy in PG, but only if combined with proper immunosuppression^.[7-10].

Ileostomy for fecal diversion as in other perianal septic and ulcerative conditions (such as perianal Crohn’s disease or Fournier’s gangrene) is also controversial but was made to decrease wound contamination and to promote faster wound healing, especially taking into account the possibility of fistulization to the rectum [11].

In this study, we show an extensive perineal PG in a patient with UC that was successfully treated with infliximab, derivation ileostomy, and NPWT.

Informed patient consent was obtained for publication of the case details.

The authors have no conflicts of interest.

M.S. wrote the manuscript, M.A.C., A.C.S., J.L., A.R., and J.C. reviewed the manuscript and followed the patient.