Pyoderma gangrenosum in a 2 1/2 year old boy

A 2 1/2 year old boy from Yatiyanthota presented with rapidly spreading leg ulceration of one month's duration. The large ulcer involving most part of the right calf had a characteristic violaceous, undermined edge surrounded by a peripheral zone of erythema. A diagnosis of Pyoderma gangrenosum was supported by a dense dermal neutrophilic infiltrate with few giant cells on histology. The condition improved dramatically to systemic steroids. Extensive investigations did not reveal any other associated disease.