The absence of ganglion cells (GCs) is the primary anatomic abnormality in Hirschsprung disease. Light microscopy is the mainstay in establishing this diagnosis. However, establishing a condition of aganglionosis may be challenging on routine H&E-stained sections of colonic biopsies and resections. We studied the identification of GCs by retinoblastoma oncoprotein (ret) immunoreactivity and routine H&E light microscopy by evaluating 53 blocks from 34 patients demonstrating GCs on original H&E-stained sections and 55 blocks from 38 patients lacking GCs on original H&E-stained sections. All blocks demonstrating GCs on H&E-stained sections also were positive for GCs on ret staining (100%). In 3 blocks that were negative for GCs by H&E staining (5%), GCs were shown on ret-stained sections. Immunoreactivity for ret has comparable specificity but slightly higher sensitivity to routine light microscopic evaluation in identifying GCs. GCs are identified more readily by ret immunoreactivity than by routine morphologic examination.

A 46-yr-old man presenting with biliary obstruction from an intrapancreatic tumor underwent pancreaticoduodenectomy. The pathology report showed the tumor to be an enteric duplication cyst. Diagnostic imaging features and operative management are discussed.

In mice inoculated with murine cytomegalovirus (MCMV) an acute myopericarditis developed which varied from a focal lymphohistiocytic inflammation to intense inflammation with necrosis and cytomegalic inclusion-bearing cells. Sublethal doses caused focal transient nonspecific chronic inflammation, followed months later by an increased frequency and extent of dystrophic cardiac calcification. When such latently infected hearts were heterotopically transplanted into uninfected animals which were then immunosuppressed (IS), a fatal generalized CMV infection followed. Cytomegalic inclusion-bearing endothelial, fibroblastic, and myocardial cells were seen in the intense inflammation found in hearts taken from mice 4 days after lethal inoculation and transplanted into uninfected mice, which were then IS. These findings may be relevant to human cardiac transplantation because they show that MCMV regularly causes cardiac infection with both acute and chronic consequences; chronic injury may follow a morphologically nonspecific myopericarditis which might not be attributed to CMV infection.

Presentation of CaseA 21-year-old woman was admitted to the hospital because of abdominal pain and vomiting.She was well until seven years earlier, when she first experienced severe midepigastric pain that radiated to the back, accompanied by vomiting. During succeeding years she had repeated bouts of similar pain and vomiting and was admitted to a nearby hospital on 9 or 10 occasions. The attacks were accompanied by leukocytosis but never by documented elevation of bilirubin or amylase levels. Each episode resolved after three to six days on a clear-liquid diet and narcotics, and she felt well in the intervals. . . .