Pyoderma gangrenosum, rare parietal complication after colorectal surgery

Pyoderma gangrenosum (PG) is a rare chronic destructive inflammatory skin disease characterized by the presence of nodules and pustules with progressively enlarging ulcers and orcutaneous necrosis. In most cases PG is idiopathic, but sometimes it is associated with conditions that often have vasculitis, such as gammapathies, inflammatory bowel diseases or chronic arthritis. PG is neither infectious nor gangrenous,but some authors advanced the theory that an infectious etiology (streptococci and staphylococci) could be incriminated.Recently, there are reports in the literature stating that PG is a condition that can occur after local trauma, especially surgery.We report the case of a 73 year old man who presented himself to the Surgery Department with rectal adenocarcinoma and postoperatively developed well-demarcated, vegetative plaques,ranging from 2 to 5 cm in diameter, with central ulceration associated with necrosis and a purulent secretion, delimitated by raised, dusky erythematous borders. These lesions were located on the abdomen and it is important to mention that the injuries occurred at the site of surgical stitches used during the rectum amputation surgery, with no other anatomical locations,pruritus or pain associated. We performed two different histopathological examinations for this patient, regarding the rectal specimens and the cutaneous specimen. The first examinations revealed rectal adenocarcinoma and nonspecific colitis. The second examination was concluded with the diagnosis of pyoderma gangrenosum, the ulcerative stage. The patient had a very good clinical response to systemic steroid therapy.