[Clinical patterns and treatment of pyoderma gangrenosum in a French department]

Pyoderma gangrenosum (PG) is a rare inflammatory neutrophilic dermatosis for which accurate epidemiological data are limited and therapy remains a challenge. The primary study aim was to examine all cases of PG observed in our regional department over a 15-year period in order to describe the relevant characteristics and outcome under therapy.

The medical records of all patients with PG from 1997 to 2012 in the Marne department of France were studied retrospectively. Clinical and histological characteristics, comorbidities, therapeutic modalities and outcome were analysed.

Forty-two patients were included (30 women, 12 men). A classical, ulcerative form was found in 39 cases and PG was multifocal in 28 cases. The number of lesions did not differ according to age or the presence of comorbidities. The most frequent first-line treatments were doxycycline (23 cases) and oral corticosteroids (15 cases), regardless of age, number of lesions or existence of comorbidities. Complete remission of PG was obtained in 38 cases (median time to remission: 3 months), with relapse occurring in 17 patients (median time to relapse: 12 months after treatment withdrawal). After a median follow-up of 46 months, 8 patients had died (median time to death: 26 months after treatment initiation).

This is the first large French series of patients presenting PG and enabling determination of the annual incidence within the Marne department at around 4.6 cases/1000,000 inhabitants. Our study illustrates the value of first-line treatment with tetracycline, which merits confirmation by further prospective, controlled studies.