Pulmonary manifestations of pyoderma gangrenosum: 2 cases and a review of the literature.

Pyoderma gangrenosum (PG) is a rare ulcerative neutrophilic dermatologic disease that occasionally is accompanied by extracutaneous manifestations, amongst these is pulmonary involvement. The etiology is unknown. More than 50% of PG cases are associated with an underlying systemic disease such as inflammatory bowel disease, rheumatoid arthritis, hematological disorder or malignancy. Extracutaneous manifestations are rare and only 29 cases of pulmonary involvement have been reported previously in the literature. Pyoderma gangrenosum is usually diagnosed in the third to sixth decade, but early debut in childhood is also described. Skin manifestations are usually evident before pulmonary involvement, although primary lung affection is seen. Pulmonary involvement is diagnosed simultaneously or from a few weeks up to several years after the diagnosis of cutaneous PG. The most important differential diagnoses are lung cancer, lung abscess and Wegener's granulomatosis. Histological specimens will exclude these diagnoses. The treatment of PG is immune modulation, but due to the rarity of the disease, only one randomized treatment trials exists [1] and the long term course of PG with pulmonary involvement is unknown. We present two cases of pulmonary manifestations of pyoderma gangrenosum and a review of the literature.