Pyoderma gangrenosum: a report of 21 cases

Background Pyoderma gangrenosum (PG) is an uncommon, destructive, cutaneous ulceration, belonging to the neutrophilic disease spectrum. It is associated with systemic disease in 50% of cases. Methods We report a retrospective study of 21 cases of PG. All cases studied fulfilled the following criteria: (i) clinical features of PG; (ii) histopathology consistent with a diagnosis of PG, and excluding other specific dermatoses. Results The average age of our patients was 41.8 years. The male to female ratio was 1.1. The typical ulcerative variant was found in 17 patients, bullous PG in two patients, and the granulomatous variant in two patients. Sixty-two per cent of our patients had lesions on their lower legs. Two patients had neutrophilic pulmonary involvement concurrent with the ulcers. An association with other internal diseases was noted in 12 patients. Histopathologic study showed vasculitis in 13 patients. Of these, 11 were leukocytoclastic and the others predominantly lymphocytic. Conclusions PG is a rare disease, with the ulcerative variant being most frequent. The lower legs are the most commonly affected sites. The recurrence rate in our study was about 46% regardless of the treatment prescribed. Pulmonary involvement was fatal in two patients.