New monoclonal antibody-based test for Helicobacter pylori urease in gastric tissue.

BACKGROUND/AIMS: To evaluate a new monoclonal antibody for Helicobacter pylori urease in gastric tissue. METHODS: A total of 107 volunteers were enrolled. All subjects underwent a (13)C-urea breath test and esophagogastroduodenoscopy. Gastric aspirates were analyzed for pH and ammonia. Six biopsy specimens in the gastric antrum and body were obtained for a rapid urease test and histology. The new monoclonal antibody-based H. pylori urease test (HPU) was performed to rapidly and qualitatively detect urease in two biopsy specimens. RESULTS: H. pylori infection was diagnosed in 73 subjects. The sensitivity and specificity of the HPU was 89% and 74%, respectively. The subjects were divided into two groups: one with true-positive and true-negative HPU results (n = 90) and the other with false-positive and false-negative HPU results (n = 17). Across all subjects, ammonia levels were 900.5 ± 646.7 and 604.3 ± 594.3 µmol/L (p > 0.05), and pH was 3.37 ± 1.64 and 2.82 ± 1.51 (p > 0.05). Sensitivity was higher in the presence of atrophic gastritis or intestinal metaplasia. CONCLUSIONS: HPU detected H. pylori in approximately 10 min. Gastric aspirate ammonia and pH levels did not affect the test results. Sensitivity was good in the presence of atrophic gastritis or intestinal metaplasia.

Detection of Helicobacter pylori in Gastric Aspirates Using a Monoclonal Antibody-Based Test.

BACKGROUND/AIMS: The objective of this study was to evaluate a monoclonal antibody-based test to detect Helicobacter pylori-specific antigen in gastric aspirates from humans. METHODS: Sixty-one volunteers were enrolled in the study. All of the subjects underwent a (13)C-urea breath test (UBT) before esophagogastroduodenoscopy. Gastric aspirates were analyzed for pH and ammonia and used for polymerase chain reaction (PCR), culture, and monoclonal antibody-based detection of H. pylori. Multiple biopsies of the gastric antrum and body were obtained for a rapid urease test (RUT) and histological evaluation. RESULTS: Thirty-six subjects were H. pylori-positive and 25 were H. pylori-negative according to the UBT results. Compared with the H. pylori-negative subjects, H. pylori-positive subjects had a higher pH (4.77±1.77 vs 3.49±1.30, p<0.05) and ammonia level (1,130.9±767.4 vs 184.2±126.3, p<0.0001). The sensitivities and specificities of the PCR test, RUT, culture test, and monoclonal antibody-based test were 100% and 72%, 89% and 100%, 47% and 100%, and 78% and 100%, respectively. CONCLUSIONS: The monoclonal antibody-based test for diagnosing H. pylori infection in gastric aspirates has increased sensitivity compared with the culture test and specificity as high as that of the RUT. The test may be useful as an additive test for examining gastric aspirates.

[Culture and polymerase chain reaction of Helicobacter pylori from rectal and terminal ileal fluid after polyethylene glycol (colyte) ingestion in healthy adults with positive urea breath test].

BACKGROUND/AIMS: Helicobacter pylori (H. pylori) transmission route is not yet clearly understood. Isolating H. pylori from stool, saliva, and vomitus is very difficult. However, H. pylori could be cultured from feces in the setting of rapid gastrointestinal tract transit. The aim of this study was to isolate H. pylori by culture and PCR in the rectum and terminal ileum during colonoscopy. METHODS: Twenty subjects with positive UBT (urea breath test) were included. We performed polymerase chain reaction (PCR) test and culture of H. pylori with the rectal fluid and terminal ileal fluid during colonoscopy. RESULTS: H. pylori was cultured with rectal fluid from 9 (45.0%) of 20 subjects and with ileal fluid from 11 (55.0%) of 20 subjects. H. pylori was a little more frequently cultured from the terminal ileal fluid than the rectal fluid without statistical significance (p>0.05). PCR test detected flaA (16/20, 80.0% and 17/20, 85.0%), 16S rRNA gene (16/20, 80.0% and 17/20, 85.0%), cagA (10/20, 50.0% and 12/20, 60.0%), and ureC (9/20, 45% and 11/20, 54.5%) from the rectal fluid and the terminal ileal fluid, respectively. The specificity and sensitivity of ureC were 100%. CONCLUSIONS: H. pylori could be cultured from the rectal fluid and terminal ileal fluid in the setting of rapid gastrointestinal tract transit. These results suggest of fecal-oral transmission of H. pylori.

[A case of macroscopically unvisualized mucin-hypersecreting biliary papillomatosis diagnosed by microscopy].

The mucin-hypersecreting biliary papillomatosis is a premalignant neoplasm characterized by intraductal papillary proliferation involving extensive areas of the intrahepatic and/or extrahepatic bile duct. We report a case of mucin-hypersecreting biliary papillomatosis manifested as obstructive jaundice and diagnosed only by microscopy, with a review of literatures. A 74-year-old female, who had a past history of cholecystectomy about 13 years ago, was admitted to our hospital with jaundice. A CT scan showed marked dilatation of intrahepatic and extrahepatic bile duct without intraductal filling defect or extrabiliary mass. During endoscopic retrograde cholangiopancreatography, mucin extrusion from the duodenal major papilla and dilated common bile duct with amorphous filling defects was noted. Percutaneous transhepatic biliary drainage for cholangioscopy was failed. In the operation field, there was a lot of mucin but was no visible mass at the common bile duct with bare eyes and cholangioscopy. However, papilloma was detected at the random biopsy specimen by microscopy. The patient underwent partial resection of common bile duct and choledocho-jejunal anastomosis.

[Three sporadic cases of acute hepatitis E].

Acute hepatitis E is an endemic disease, commonly reported in Indian subcontinent, China, Africa, Central America, and so forth. It is a self-limiting disease like other acute hepatitis except in pregnant patient. Although sporadic hepatitis E is noted all over the world, most of them are associated with travel history to HEV-endemic area. In Korea, Hepatitis E is rarely reported. Moreover, sporadic acute hepatitis E without travel history to HEV-endemic area is very rare. We experienced three sporadic cases of acute hepatitis E, without travel history. All of them presented acute hepatitis symptoms, elevated aminotransferase, and positive IgM HEV Ab. Symptoms and aminotransferase levels were normalized during hospitalization and IgM HEV Ab converted negative after 4-8 months. We report three sporadic cases of onset-acute hepatitis E without travel history to HEV-endemic area.

[Telomerase expression in colorectal tubular adenoma determined by immunohistochemical staining].

BACKGROUND/AIMS: Telomeres are simple repeat elements located at each chromosome end of eukaryotic cells. The main function of telomeres is to cap the chromosome end and protect it from enzymatic attack. Telomerase that facilitates the synthesis of telomere has been detected in not only cancer but also precancerous lesion. In this study, we compared the telomerase expression between low grade and high grade colorectal tubular adenoma. METHODS: Among tissues from forty eight patients with colorectal tubular adenoma (23 low grade and 25 high grade colorectal dysplasia), telomerase expressions were evaluated by immunohistochemical staining. RESULTS: We classified 48 patients into two groups by the extent of nuclei staining pattern. High telomerase expression was a group which showed staining nucleus pattern above 50% in tubular adenoma. Low telomerase expression was a group which showed staining pattern nucleus below 50%. Twelve in 25 high grade colorectal dysplasia showed high telomerase expression (48%). Only one in 23 low grade colorectal dysplasia showed high telomerase expression (4%). Telomerase expression was much higher in the tissues from the patients with high grade than in those with low grade colorectal dysplasia (p<0.05). CONCLUSIONS: Activation of telomerase may be related to the malignant potential in colorectal epithelial cells. Further studies are needed to define the role of telomerase in colorectal tumorigenesis.

[Clinical outcomes after discontinuation of Lamivudine in chronic hepatitis B patients with Lamivudine resistant HBV mutant].

BACKGROUND/AIMS: The therapeutic strategies of applying adefovir for treating lamivudine resistant HBV mutants are controversial. Thus, we observed the clinical outcomes after discontinuation of lamivudine to establish the timing to initiate adefovir therapy. METHODS: Fifty chronic hepatitis B (CHB) patients with lamivudine resistant HBV mutants who had received lamivudine for more than 12 months were included in the study. We investigated the clinical outcomes at 6 months after the end of treatment (EOT). We compared the serial clinical outcomes among respective groups based on serum ALT at the EOT and the clinical characteristics of patients with or without acute exacerbation (AE) and the HBeAg loss. We also investigated the predictive parameters of AE and HBeAg loss. RESULTS: Fifteen patients (30%) had experienced AE at 6 months after the EOT. Four patients received antiviral agents because of their hepatic decompensation. Patients with AE had higher serum ALT values and lower HBV DNA titers at EOT compared with those patients without AE. Serum ALT at the EOT was the predictive parameter of AE. Eight patients (21.6%) had newly developed HBeAg loss at 6 months after EOT. The total bilirubin at EOT was the predictive parameter of HBeAg loss. CONCLUSIONS: CHB patients with lamivudine resistant HBV mutants had favorable clinical outcomes at 6 months after EOT. Therefore, we can consider observing the clinical courses after discontinuation of lamivudine and it is not always required to overlap the adefovir for treating lamivudine resistant HBV mutants except for the treatment of patients with a high risk of developing decompensation.