Year: 2014
Type: article
Study design: Case Report
Abstract: A 55-year-old Caucasian man with a history of polycythemia vera and subsequent progression to myelofibrosis underwent an open splenectomy for symptomatic splenomegaly and cytopenias. On postoperative day 6, two areas of necrosis developed along the midline incision site. The areas of necrosis expanded over two days and did not respond to empiric broad-spectrum antibiotics. Although the patient remained afebrile, peri-incisional pain intensified. Intraoperative sterile technique had been maintained, and postoperative cultures were negative. A dermatologist was consulted because of an "unusual wound breakdown" on day 8. At consultation, the patient reported extreme pain and tenderness around the involved areas of the incision. Physical examination showed two peri-incisional necrotic and indurated plaques with violaceous bullous borders (Fig. 1). Superficial skin dehiscence was noted. Histopathologic analysis of a skin biopsy from the edge of the ulceration demonstrated dense dermal neutrophilic inflammation with intraepidermal neutrophilic abscess formation and papillary dermal edema (Fig. 2). Pyoderma gangrenosum (PG). Pyoderma gangrenosum is a neutrophilic, inflammatory, ulcerative dermatosis that can localize to any site of trauma and is often associated with systemic disease. The four clinical subtypes of PG are classic ulcerative, pustular, bullous, and vegetative superficial (granulomatous) PG. Classic ulcerative PG presents as a rapidly evolving ulcer with a necrotic undermined border and may begin as a pustule on an erythematous or violaceous base. The pustular form presents as a generalized pustular eruption without eventual ulceration and is commonly seen in association with inflammatory bowel disease (IBD). Bullous PG presents as painful superficial blisters with associated necrosis and erosion, especially in the setting of myeloproliferative disease. Vegetative PG is a chronic form of PG characterized by painless, superficially ulcerative, verrucous lesions commonly occurring on the trunk.1, 2 The clinical differential diagnosis of PG includes infections, vasculitis, vasculopathies, neoplasms (e.g. leukemia and lymphoma cutis, squamous cell carcinoma, and other malignancies), and factitious ulcerations. A cutaneous biopsy will aid in distinguishing among these clinical entities. The histopathologic hallmark finding of PG is dermal neutrophilic abscess formation, although the histopathologic features are nonspecific; therefore, the diagnosis of PG is one of exclusion. The histopathologic differential diagnosis of PG includes infections and other neutroph-ilic dermatoses, including Sweet syndrome, neutrophilic dermatosis of the dorsal hand, and bowel bypass syndrome. These diagnoses are distinguished by clinicopathologic correlations, tissue cultures, and special microorganism stains on skin biopsy sections including those for bacteria, mycobacteria, and fungi. In the ulcerative form, there is associated overlying ulceration. Pustular PG is characterized histologically by intraepidermal neutrophilic abscesses and perifollicular neutrophilic inflammation. In bullous PG, as illustrated in our case, intraepidermal blister formation and intraepidermal neutrophilic abscesses are seen. Vegetative PG is characterized by epidermal hyperplasia and dermal granulomas.3-6 Typically, half of patients with PG have an underlying systemic illness, such as IBD, rheumatoid arthritis, or a myeloproliferative disorder.7 Although IBD is often associated with PG, the relationship is not exclusive. As the present case demonstrates, myelodysplastic syndrome, myelofibrosis, and other myeloproliferative disorders may be present.8 Our patient had myelofibrosis secondary to polycythemia vera, which has also been described in association with PG.9-11 Pyoderma gangrenosum associated with bullous blue–gray margins, as in the present patient, is designated atypical and often occurs concomitantly with hematologic malignancies such as myelodysplastic syndrome.7, 12-14 Interestingly, PG may herald the diagnosis of a myeloproliferative malignancy years in advance and may subsequently be used as a prognostic factor.15-17 An unusual, but not pathognomonic, phenomenon illustrated in PG is pathergy. Similarly to symptoms seen in Behçet's disease, pustular and subsequently ulcerative PG lesions may develop at sites of trauma, a type of phenomenon known as "pathergy".7, 18 Camargo et al.19 recently clarified the distinction between the Koebner phenomenon and pathergy. They noted that the isomorphic Koebner phenomenon generates a lesion of the specific disease in an area of trauma. By contrast, pathergy refers to the formation of nonspecific lesions, not unique to skin, exemplified by application of a test such as a needle stick test, without formation of a specific lesion of the underlying disease. Pathergy is often associated with Behcet's disease, PG, Sweet syndrome, and IBD. A clinician's awareness of pathergy in cases of PG is particularly crucial in the perioperative period. Postoperative PG, which has been described in the multidisciplinary literature including in the fields of orthopedic, cardiothoracic, general, and gynecologic surgery,15, 20-24 can lead to slow wound healing, dehiscence, and the possible misclassification of PG as a wound infection. Surgeons may then choose to initiate antibiotic therapy and debride the wound, which, in turn, would lead to further progression of the PG. Inappropriate debridement can cause additional pathergy, wound breakdown, and adverse reactions to antibiotics administered, which could potentially be devastating. Hence, recognition of this phenomenon and early consultation with a dermatologist can lead to a diagnosis and the initiation of proper treatment. The treatment of PG is controversial and varies depending on the associated systemic disease, the setting, and the extent of involvement. Typically, PG is treated with corticosteroids and steroid-sparing agents; however, only infliximab in the setting of IBD has been prospectively studied.25 A prospective trial comparing the effects of oral prednisolone and cyclosporine is currently underway.26 Corticosteroids are used in the overwhelming majority of idiopathic PG cases; steroid-sparing agents can include tetracyclines, dapsone, mycophenolate mofetil, intravenous immunoglobulin, tumor necrosis factor-α inhibitors, and other immunomodulatory or immunosuppressive agents. In the roughly 50% of PG cases associated with systemic illnesses, disease-specific therapy may be used with adjunctive corticosteroid therapy. Although controversial, surgical intervention, such as split-thickness skin grafting with concomitant immunosuppressive therapy, can be considered in order to accelerate wound healing.27, 28 Our patient was treated with oral prednisone 60 mg daily, as well as minocycline 100 mg twice daily and tacrolimus 0.1% ointment applied to the violaceous edges. The corticosteroids were then tapered over several weeks, paralleling the patient's response to therapy, which was gauged by a decrease in pain and the resolution of the ulceration (Fig. 3). Perioperative corticosteroid or anti-inflammatory therapy may be considered in high-risk patients with previously reported postoperative PG. In summary, PG is a neutrophilic dermatosis often associated with systemic diseases. Pathergy is an important phenomenon demonstrated by trauma-induced cutaneous lesions of PG and can occur at incisional sites in the postoperative setting.29 The present report describes a patient with myelofibrosis, a condition infrequently associated with PG, with pathergy at the site of splenectomy, and an excellent response to systemic immunomodulatory and anti-inflammatory therapy. Additional studies describing the relationship between PG and myeloproliferative disorders, as well as postoperative PG, might better illuminate these associations and educate physicians on their recognition and treatment.
DOI: 10.1111/ijd.12697
Institution: Mayo Clinic
Language: English
Subfield: Epidemiology
Field: Medicine
Domain: Health Sciences
Open Access status: bronze
OpenAlex ID: W2074475371