CASE REPORT:
A 45-year-old Nepalese female presented with 4 months history of moderately itchy erythematous plaque on bilateral soles with few discrete pustules and yellow brown crust. Three months after onset of lesions, she developed multiple pustules on erythematous base over the extensor aspect of left leg associated with moderate pain. These pustules ruptured to form ulcers over 3-4 days and coalesced rapidly over 1-2 weeks to forma a large ulcer of irregularly shape, undermined edge, measuring 10×8 cm2 and non-foul smelling scanty serous discharge on floor and hyperpigmented surrounding skin. There was no history of trauma prior to the onset of lesion, significant weight loss, fever, arthralgia or gastrointestinal symptoms and was nonsmoker.
The biopsy specimen from the edge of the leg ulcer showed a hemorrhagic ulcer adjoining an intact epidermis with large necrotizing suppurative dermal inflammation, leukocytoclastic vasculitis within central suppurative zone, angiocentric and intraneural lymphocyte infiltration and uninvolved zones showed normal hair follicles and adnexal structures surrounded by lymphocytes (Fig 1 a, b and c). Special stains were negative for organism, tuberculous bacilli, mucin or fibrin.
Other laboratory tests, including complete blood count, liver and renal functions, erythrocyte sedimentation rate and chest X-ray were unremarkable. A culture from the ulcer did not demonstrates any pathogenic organisms. A diagnosis of classical ulcerative type of pyoderma gangrenosum with palmoplantar pustulosis was made. She was treated with a tapering dose of oral prednisolone (50 mg/ day), and the ulcer healed within 1 and 1/2 months to leave an atrophic scar. Then the patient was lost to follow up.
Four months later, she developed again multiple pustules over previously healed atrophic scar with similar progression as in the previous episode to form a larger ulcer. On examination, an irregular shaped ulcer approximately 7×4 cm2 was present over lower 1/3rd of dorsum of left leg with undermined edge and hyperpigmented border with scanty serous discharge, granulation tissue and adherent yellowish crust on the floor. Similar smaller ulcers approximately 1-2 cm2 were present on the periphery of larger ulcer. The ulcer was tender with mild induration of the borders. An atrophic plaque with hyperpigmented margin was present on the dorso-lateral aspect of leg surrounding the ulcer (Fig. 2 a and b). Similarly, on bilateral soles, well defined erythematous plaque with semi adherent whitish scales with multiple adherent yellow brown crust and few pustules was present (Fig.2 c and d). Nail examination revealed yellowish discoloration, distal onycholysis, few pits on almost all nail plates of bilateral hands and feet with subungual hyperkeratosis of great toes (Fig 2 e and f).
Biopsy of the erythematous plaque on right sole showed hyperkeratosis with parakeratosis with munro’s micro-abscess and psoriasiform hyperplasia of epidermis (Fig 3 a, b and c).
laboratory tests including complete blood count, liver and renal functions, erythrocyte sedimentation rate and chest X-ray were unremarkable. The culture of wound swab was sterile. The patient was admitted in the dermatology ward and was given 8 mg dexamethasone intravenously for 5 days, which was later changed to oral prednisolone 80 mg per day along with wound care. The patient was also started on tablet methotrexate 15mg per week. The ulcer showed rapid improvement over 1 week with 30-40% improvement in pain and discharge and 15 % improvement in the size of the ulcer (Fig. 2 g and h). The ulcer of PG and lesions of PPP showed about 90% improvement after 4 weeks of treatment (Fig. 2 i and j). The dose of prednisolone was tapered weekly 10mg for 4 weeks and then every 2 weeks till 10 mg. The dose of methotrexate was increased to 20 mg per week after 6 weeks and then tapered to 17.5 mg/week dose which she continued for 4 weeks. The patient was unable to come for follow up and she stopped all medicines after 20 weeks of initiating treatment. However, she visited OPD after 9 months and was on complete remission with healed scar on the site of previous ulcer (Fig 2 k, l m and n) with significant improvement on nails (Fig 2 o and p).