Enteritis necroticans 'pigbel' in a Japanese diabetic adult.

Enteritis necroticans 'pigbel' is caused by Clostridium perfringens type C but has rarely been reported in developed countries. A 50-year-old Japanese man with untreated diabetes mellitus (DM) presented with diarrhea and abdominal pain. Intraoperative endoscopic and macroscopic examination disclosed segmental annular mucosal lesions characteristic of clostridial enteritis. Clostridial infection type C was verified on pathological, and immunohistochemical analysis. Although rare, the disease is likely to be underdiagnosed. Hence, the pathology and immunohistochemistry of segmental enteritis with annular mucosal lesions should be examined to establish a diagnosis of enteritis necroticans even in mildly affected patients, and especially those with DM.

Pancreatic cancer initially presenting with a pseudocyst at the splenic flexure.

Pancreatic cancer and pancreatitis associated pseudocyst are not uncommon disorders. However, occurrence of the cancer with an initial manifestation of pseudocyst has been rarely reported. Surgery was performed on a 44-year-old male patient for an abscess-like cavity situated at the mesenteric side of the colon and extending from the splenic flexure to the descending colon. The lesion was verified as a pseudocyst with fat necrosis due to leakage of pancreatic fluid. When further surgery was carried out 1 month later in order to manage the drainage site of the pancreatic fluid, cancer of the pancreas body was detected proximal to the drainage site. The cancer was a moderately differentiated ductal adenocarcinoma with wide peripancreatic infiltration. It is thought that the cancer-associated duct obstruction caused a local pancreatitis resulting in a large communicating pseudocyst, although the exact mechanism remains unresolved. The present case may be instructive in showing physicians that a pseudocyst may obscure the presence of pancreatic cancer.

Small bowel strangulation caused by parasitic peritoneal strand.

A 51-year-old woman with a history of eating raw fish over a period of 2 weeks developed a progressive abdominal pain and leukocytosis with signs of small bowel obstruction. Eosinophilia was not detected in the peripheral blood. The patient underwent surgery to clarify the possibility of ileus. Partial small bowel near the ileum was trapped by a peritoneal strand and was strangulated for approximately 30 cm in length with congestion and edema. The removal of the strand easily released the strangulation and the small bowel returned to a normal appearance. Pathologically, the strand consisted of granulomatous inflammation with a wide zone of necrosis containing a dead ghost feature of a parasite in its center. The necrosis was surrounded by palisading spindle cells with largely lymphocytic infiltration and a few eosinophils. In the parasite, there presented the polymyalian type muscle layer, ventricles and Renette cells, which suggested that the parasite is compatible with the third stage larva of Anisakis type I, leading to the diagnosis of ectopic anisakidosis. It should be noted that, on rare occasions, Anisakis larva migrans can form a peritoneal strand with a wide zone of necrosis and cause strangulation ileus, especially in populations with the habit of eating raw fish.