Faculty Bibliography

BACKGROUND & AIMS/OBJECTIVE:The clinical significance of "fullness" or enlargement of the pancreas (FP/EP) is not well established. The objective of this study was to report our experience with endoscopic ultrasonography (EUS) in evaluating patients referred for FP/EP found on computed tomography (CT). METHODS:Patients referred to our center for EUS evaluation of FP/EP between January 1998 and December 2003 were studied. Patient demographics, clinical history, endoscopic findings, and follow-up were recorded. Multivariate analysis was used to identify predictors of pancreatic malignancy. RESULTS:A total of 50 patients: 46% (23/50) male, mean age 59 years (range, 18-90) made up our studied population. EUS demonstrated normal findings in 42% (21/50), prominent ventral anlage (embryologic variant) in 14% (7/50), and chronic pancreatitis in 22% (11/50). In 22% (11/50), a suspicious mass was noted and fine-needle aspiration (FNA) was performed. Cytology revealed chronic inflammation in 7 patients, while adenocarcinoma was found in the remaining 4. Median follow-up was 27 months, and the diagnosis did not change in any of the 50 patients. There were no procedure-related complications. After multivariant regression analysis, the factors that were statistically associated with malignancy were a CA19-9 level >300 (P = .0002) and weight loss (P < .006). CONCLUSIONS:The majority of patients presenting with FP/EP had benign disease, but 8% had pancreatic cancer. Elevated CA19-9 and weight loss were predictive of pancreatic malignancy. EUS and EUS-FNA are safe and accurate diagnostic tests and can play an important role in evaluating patients with FP/EP.

BACKGROUND:Delayed gastric emptying (DGE) occurs in 14% to 61% of patients after pylorus-preserving pancreaticoduodenectomy, but its pathogenesis is unclear. We hypothesized that DGE may be due to pylorospasm secondary to vagal injuries at operation and may be preventable by the addition of pyloromyotomy. METHODS:Patients operated on consecutively between April 2000 and August 2003 were studied. Pyloromyotomy was of the Fredet-Ramstedt type combined with antroplasty. DGE-free recovery was defined as tolerance of a diet for three successive days by postoperative day 8. The symptom of nausea was used as a basis for nasogastric tube removal and diet resumption. A gastric emptying test (GET) with solid food was obtained. Patients with difficulty swallowing were fed via a feeding tube. RESULTS:There were 47 patients. Two patients were excluded because of death (n = 1) and ileus with pancreatic fistula (n = 1). Diagnoses were pancreatic cancer (n = 23), chronic pancreatitis (n = 11), ampullary cancer (n = 5), mucinous cystic neoplasm (n = 5), and duodenal villous adenoma (n = 3). Median times to nasogastric tube removal, start of liquid diet, and start of solid diet were postoperative days 2, 3, and 5, respectively. Two patients had tube feedings. Preoperative GET was abnormal in 51%, and postoperative GET was abnormal in 37%. The average length of stay was 9.5 days (median, 7 days). DGE occurred in only one patient (2.2%). There were no late complications during a 6-month follow-up. CONCLUSIONS:The addition of pyloromyotomy to pylorus-preserving pancreaticoduodenectomy is effective in preventing DGE. Results are supportive of the hypothesis that DGE may be caused by operative injuries of the vagus innervating the pyloric region.

A number of genetic mutations have recently been identified that appear to be important in the development of pancreatitis. Point mutations in the cationic trypsinogen gene are capable of initiating pancreatitis. These mutations also provide important insights into the pathophysiology of acute pancreatitis and into potential connections between acute and chronic pancreatitis. Mutations in the genes encoding for the pancreatic secretory trypsin inhibitor and the cystic fibrosis transmembrane conductance regulator more likely work in concert with other genes and environmental factors in affecting disease susceptibility. Although the subject so far has received only a limited amount of study, genetic polymorphisms in a wide range of genes relating to pancreatic function and to regulation of inflammation are likely to play major roles in determining each individual's susceptibility to developing pancreatitis, and its severity if it does develop.

BACKGROUND:EUS-guided fine-needle aspiration is rapidly becoming the procedure of choice for the diagnostic evaluation of pancreatic masses. Acute pancreatitis has been reported after EUS-guided fine-needle aspiration of the pancreas. This study evaluated the effect of EUS-guided fine-needle aspiration on the pancreas by serial measurement of amylase and lipase levels and determining the frequency of acute pancreatitis after EUS-guided fine-needle aspiration of pancreatic masses. METHODS:In 100 consecutive patients referred for EUS-guided fine-needle aspiration of a pancreatic mass, amylase and lipase levels were determined immediately before and within 2 hours after the procedure. Additionally, patients were questioned as to the occurrence of symptoms of acute pancreatitis within 48 hours after EUS-guided fine-needle aspiration. RESULTS:For 2 of 100 patients (2%) there was clinical and biochemical evidence of acute pancreatitis after EUS-guided fine-needle aspiration. Both patients had a history of recent pancreatitis. In addition, there was a significant increase in postprocedure lipase levels (p = 0.40) compared with amylase levels in this patient subset. CONCLUSION/CONCLUSIONS:The frequency of acute pancreatitis after EUS-guided fine-needle aspiration of the pancreas was 2% in this study. A history of recent pancreatitis appears to be a potential risk factor. Amylase and lipase levels can be elevated after EUS-guided fine-needle aspiration and in most cases have no clinical significance.

Cytomegalovirus (CMV) can be an important opportunistic infection in HIV-1-infected patients, particularly when the CD4+ T-cell count drops below 50 lymphocytes/mm3. CMV-associated disease, including retinitis, pneumonitis, gastroenteritis, and encephalitis, is estimated to affect up to 40% of AIDS patients. We have studied the cellular immune response to CMV in gut-associated lymphoid tissue (GALT) of HIV-1-infected patients. Two patients with chronic diarrhea of unknown etiology were examined by flexible sigmoidoscopy and upper endoscopy. Biopsy specimens were obtained from lymphoid-associated tissue sites in rectum and duodenum. Both patients were seropositive for CMV IgG, but had not been treated with ganciclovir, and neither had clinical signs of CMV disease. Mononuclear cell cultures were established from GALT and blood and assayed for the presence of CMV-specific CD8+ T cells. CD8+ T-cell phenotype and function were assessed by MHC Class I tetramer staining, using an HLA-A*0201 tetramer complex specific for peptide 495-503 (NLVPMVATV) of CMV lower matrix protein pp65, and by a standard 51Cr release assay. CMV pp65-specific cytotoxic lymphocytes (CTL) were detected in GALT and blood MNC from both patients. These results demonstrate that HIV-1-infected subjects seropositive for CMV, but without active CMV gastrointestinal disease, harbor CMV-specific CTL in intestinal lymphoid tissue. This is the first report of isolation of CMV-specific CTL in GALT and will lead to greater understanding of the pathogenesis of CMV disease in human mucosal tissue