Successful treatment of pyoderma gangrenosum that developed in a patient with myelodysplastic syndrome

We describe the successful treatment of pyoderma gangrenosum (PG) that developed in a patient with myelodysplastic syndrome (MDS). A 63-year-old Japanese man with MDS was admitted to our hospital because of a large skin ulcer on his neck in November 2001. The initial diagnosis was infectious dermatitis, and antimicrobial therapy was performed, using imipenem/cilastatin, isepamicin, and amphotericin B. However, this therapy was not effective, and the lesion worsened. Cultures of blood, throat swab, and ulcer pus yielded no microorganisms. A biopsy of the skin lesion revealed a severe infiltration of neutrophils in the dermis, without any evidence of infection. The lesion was finally diagnosed as PG, and systemic administration of corticosteroid hormone was started in December 2001. The patient was initially pulsed with 1 g methylprednisolone daily for 3 days. The dose was immediately reduced, and the treatment was maintained with 30 mg prednisolone daily. The skin lesion responded markedly to the therapy, and C-reactive protein became negative. The patient was discharged in February 2002 because the lesion was almost cured. Prednisolone administration was tapered after 6-month maintenance therapy. No recurrence of PG was seen, although his MDS transformed into leukemia in April 2003. Only 31 cases of MDS developing PG have been reported in the past 20 years in Japan. This report describes one such rare patient who was successfully treated with the use of high-dose pulse methylprednisolone and long-term maintenance therapy.