INTRODUCTION

Pyoderma gangrenosum (PG) is a chronic and rare autoimmune dermatosis, first described by Brunsting and O Leary in 1930, highlighting the absence of an infectious nature. Histopathologically, it is characterized by a nonspecific, noninfectious, non-neoplastic dermal neutrophilic infiltrate, without evidence of primary vasculitis¹.

The etiological basis remains little understood, being idiopathic in 25 to 50% of cases. Other cases are associated with systemic autoimmune diseases, especially inflammatory bowel disease and mainly ulcerative colitis, but also arthritis, IgA gammopathy, and others^2,3. It may also appear as a paraneoplastic manifestation or after the use of certain medications (propylthiouracil and isotretinoin in particular) and illicit substances such as cocaine⁴.

PG has an incidence of 2 to 3 cases per 1 million per year^4,5. National data from a retrospective analysis indicated that in Brazil, this rate is 0.38 cases per 10,000 clinical visits⁵, with women between the second and fifth decades of life being most affected⁴.

The clinical presentation is variable, and a single or multiple ulcerous form, which appears on a prior scar, is the most prevalent⁶. The ulcers are well circumscribed, and have a violaceous halo and necrotic-hemorrhagic center, with characteristic purulent and accelerated centrifugal growth, ending with accelerated formation of granulation tissue⁷. In addition to the ulcerated form, PG has pustular and vegetative forms, which are less prevalent and have fewer postoperative complications⁸.

Histopathology and immunohistochemistry in PG are nonspecific, and no serological markers are available for laboratory diagnosis; thus, diagnosis is clinical by default^9,10.

Knowledge of the pattern of the cutaneous lesion is important, because diagnosis of post-surgical PG can be delayed. More commonly suspected diagnoses such as wound dehiscence and infection result in unnecessary debridement that tends to worsen the clinical presentation, since the pattern of the PG lesion is related to the phenomenon of pathergy in up to 50% of cases, with minor trauma triggering new lesions^6,11.

The plastic surgeon should include the diagnosis of PG in the differential diagnosis, since the knowledge of cutaneous lesions, predisposing factors, and surgical risk factors enables avoidance of exacerbation.

CASE REPORT

A 39-year-old, previously healthy Caucasian patient, with no surgical or obstetrical history, underwent reduction mammoplasty (Figure 1), and was discharged after 24 hours without complaints and in good general condition.

Figura 1 - Immediate postoperative appearance.

Figura 1 - Immediate postoperative appearance.

The patient received antibiotic prophylaxis with cefazolin 1 g every 6 h during hospitalization, followed by cephalexin 500 mg every 6 h, until the postoperative day (POD) 7. She was reassessed 72 h after the surgical procedure, still without complaints. The surgical wound had a good appearance, and a micropore dressing was in place.

On 15 POD 15, during routine follow-up, the surgical wound presented a necrotic ulcer in a vertical scar on the left breast, with drainage of moderate seropurulent secretions (Figure 2). Debridement of devitalized tissue was performed, together with antibiotic therapy with ciprofloxacin 500 mg every 12 h and local dressings with collagenase ointment, in addition to micropore dressings. The wound initially appeared improved. On POD 17, the patient was reevaluated for significant worsening, with centripetal progression, affecting segments of the scar in the inframammary groove. The patient denied systemic symptoms.

Figure 2 - Postoperative day 10 – evolving ulcerated lesion.

Figure 2 - Postoperative day 10 – evolving ulcerated lesion.

Due to the surprising change, PG was considered. Consequently, a systematic review was performed in the literature regarding the therapeutic management of PG (Table 1).

Table 1 - Clinical and therapeutic reports on PG, searched in databases of the last 10 years.

First-line treatment was initiated with oral and topical corticosteroids. Prednisone was administered at 60 mg/day for 7 days, 40 mg/day for 7 days, 20 mg/day for 7 days, and finally 10 mg/day for 4 days, ending with 10 mg/day on alternate days, for a total of 28 days (Figure 3).

Figure 3 - Postoperative day 21 - 4 days after initiation of oral and topical corticosteroids.

Figure 3 - Postoperative day 21 - 4 days after initiation of oral and topical corticosteroids.

The topical treatment comprised daily fludroxycortide 0.125 mg/g (Drenison^®), maintained from the beginning of oral therapy until the consolidation of the scar, which occurred at the end of the 2nd postoperative month, approximately 20 days after the end of oral corticosteroid therapy (Figure 4). The patient had a favorable course, with complete closure of the lesions after treatment for 1 month. Figure 5 shows the appearance in the 3rd postoperative month.

Figure 4 - Postoperative day 30 - 13 days after initiation of oral and topical corticosteroids.

Figure 4 - Postoperative day 30 - 13 days after initiation of oral and topical corticosteroids.

Figure 5 - 3 months postoperatively - healed lesion.

Figure 5 - 3 months postoperatively - healed lesion.

DISCUSSION

PG is a devastating complication both for the patient and the plastic surgeon, leading to questions about the technical quality of the surgical procedure¹². The absence of a supplemental exam that confirms the diagnosis of PG, combined with nonspecific findings on histopathology, requires clinical knowledge of this disease to enable diagnosis^1,2,4.

The objective of treatment is to limit tissue destruction, promote healing, and obtain a good esthetic result. Debridement and skin grafts are contraindicated^3-5.

First-line treatment with systemic corticosteroids is the most effective option for PG. Immunosuppressive doses are necessary in the majority of cases, with approximately 100-200 mg/day of prednisolone or 60-80 mg/day of prednisone ^4,6,7.

Alternatively, cyclosporine, at doses of 6-10 mg/kg/day, can produce significant improvement, with healing in 1 to 3 months, and is indicated for a minority of patients who do not respond to steroid therapy^7,8.

TNF-alpha inhibitors, such as infliximab, show good results in some patients^10,12.

Hyperbaric oxygen therapy may be indicated for patients who cannot tolerate or do not respond to high doses of systemic corticosteroids; however, the therapeutic result is less effective, as demonstrated in some case series¹¹. Topical therapy is indicated to complement systemic therapy; corticosteroids alone are the drugs of choice in selected cases of lesser severity^6,7,11.

Antibiotic therapy is not supported for PG cases, as demonstrated in all series studied; therefore, there are no clinical benefits from the use of antimicrobial agents in these patients^7,9.

With regard to future plastic surgery, the patient should be advised about the likelihood of recurrence of PG, and this point should be explained in an Informed Consent Form to be signed by the patient. Long-term follow-up with a rheumatologist is recommended, as other autoimmune disorders may be found^7,9,12.