Multiple abdominal nodules in a patient with ulcerative proctitis: a case of peritoneal splenosis

A 40-year old gardener was referred for ulcerative proctitis treated with topical mesalamine with rapid improvement of symptoms. Eighteen years before he had had a splenectomy for traumatic splenic rupture. At the end of 2010, he was admitted to another hospital because of abdominal pain. Computerized tomography (CT) scan and magnetic resonance imaging revealed multiple abdominal nodules but a definite diagnosis was not made. While being examined for the proctitis, the patient was admitted to our unit due to worsening of the abdominal pain. After another CT scan, a laparoscopy was performed: several reddish-blue nodules on the peritoneal wall were observed and biopsies were performed. Histological examination was consistent with splenosis. After the procedure, we observed an improvement in the abdominal pain. Splenosis is an acquired condition defined as autotransplantation of viable splenic tissue throughout different sites of the body. It occurs after splenic rupture via trauma or surgery. Splenosis is a benign condition that is usually found incidentally unless symptomatic. Since on radiographic examination it can mimic a neoplasia, extensive workup is usually needed. The diagnostic method of choice is nuclear scintigraphy. Splenosis usually occurs in the abdominal and pelvic cavities but patients have been described with splenosis in other intrathoracic, hepatic and subcutaneous sites. Splenosis is usually asymptomatic and treatment is not necessary. Most patients who have an exploratory laparotomy or laparoscopy for abdominal pain, such as in our patient, experience no more pain after the procedure, regardless of whether the splenic nodules have been completely removed or not. The reason for this spontaneous improvement is not known.