The prevalence of and risk factors for Barrett's esophagus in a Korean population: A nationwide multicenter prospective study.

OBJECTIVE: The aim of this study was to evaluate the prevalence of Barrett's esophagus (BE) in the general Korean population by evaluating screening esophagogastroduodenoscopy. In addition, the risk factors for BE were identified. METHOD: An esophagogastroduodenoscopy examination was performed in 25,536 subjects who had upper endoscopy screening from January 2006 to July 2006. RESULTS: Two hundred and fifteen subjects were confirmed to have BE by pathology, thus the prevalence of BE was calculated to be 0.84%. The endoscopic findings were subdivided into 2 groups: BE without reflux esophagitis (RE), which included 167 (77.7%), and BE with RE, which included 48 (22.3%). The analysis of symptoms showed that only 60.1% of the subjects with BE had reflux symptoms. Chest pain [odds ratio (OR): 1.48, 95% confidence interval (CI): 1.04-2.11] and epigastric soreness (OR: 1.42, 95% CI: 1.05-1.93) were found more frequently in the subjects with BE compared with the normal subjects. The multivariate analysis showed that the risk factors for all subjects with BE were a male sex (OR: 1.82, 95% CI: 1.32-2.50), nonsteroidal anti-inflammatory drug use (OR: 2.02, 95% CI: 1.28-3.20), hiatal hernia (OR: 5.66, 95% CI: 3.70-8.66), and an age > or = 60 compared with an age < 40 (OR: 1.81, 95% CI: 1.07-3.09). There was no significant difference associated with RE. CONCLUSIONS: The prevalence of BE in Korean patients presenting for a routine health check-up was 0.84%, lower than reported in Western countries. Among the subjects with BE 77.7% did not have endoscopic erosions and there were no reflux symptoms in 39.9%. These results suggest that regular endoscopic screening with a high index of suspicion is necessary for the diagnosis of BE.

EMR for early gastric cancer in Korea: a multicenter retrospective study.

BACKGROUND: EMR has been accepted as a treatment modality for selected cases of early gastric cancer (EGC) in Japan. However, long-term outcomes after EMR for EGC have not been fully documented. OBJECTIVES: We reviewed the experiences of EMR for EGC in Korea, with emphasis on the long-term outcome. DESIGN: Multicenter, retrospective study. METHODS: Data were collected retrospectively by use of the on-line database registry system. From January 2000 to December 2002, 514 EGCs in 506 patients were treated by EMR in 13 institutions in Korea. Median age of the patients was 60 years (range 45-83 years). The resection was regarded as incomplete if histopathologic examination revealed a positive resection margin or submucosal invasion or positive lymphovascular invasion or undifferentiated histologic diagnosis. RESULTS: The most commonly used technique was circumferential precutting followed by snare resection (EMR-P, n = 269, 52.3%). Complete resection and incomplete resection after EMR were confirmed in 399 lesions (77.6%) and 103 lesions (20.0%), respectively. For completely resected mucosal cancers (n = 399), the median duration of follow-up was 23.5 months (range 5-70 months). In this group, local recurrence was detected in 24 cases (6.0%) with a median interval between EMR and recurrence of 17.9 months (range 3.5-51.7 months). There were 3 cases with perforation and 71 cases with bleeding. No deaths were related to recurrence of gastric cancer during the overall median follow-up period of 39 months. LIMITATIONS: Multicenter retrospective design, no controls. CONCLUSIONS: EMR is an effective therapeutic modality for selected cases of EGC in Korea.

Perivascular epithelioid cell tumor (PEComa) in the transverse colon of an adolescent: a case report.

Perivascular epithelioid cell tumor (PEComa) is defined as a very rare mesenchymal tumor of histologically and immuno-histochemically distinctive perivascular epithelioid cells. PEComa in the colon is very rare, with only a few reported cases so far. Because of its rarity, the clinical features and biological behavior of PEComa in the colon have yet to be established. A 16-year-old female patient with PEComa in the transverse colon was referred to our hospital for rectal bleeding. Laboratory data showed a hemoglobin level of 6.6 g/dL, WBC of 8,800/mm(3), and platelet count of 191,000/mm(3). Colonoscopy, barium enema, and abdominal computed tomography revealed a 2-cm, smooth-surfaced, round tumor with focal ulceration in the proximal transverse colon. The patient complained of abdominal pain one day after endoscopic polypectomy. She underwent a segmental resection for a perforated transverse colon. Immunohistochemically, the tumor cells showed strong diffuse positivity for HMB-45 while they were negative for c-kit, smooth muscle actin, cytokeratin, S-100, vimentin, desmin, chromogranin, synaptophysin, EMA, and CD-34. The diagnosis of PEComa was based on histological and immunohistochemical staining. The patient did not receive any adjuvant therapy and was discharged on postoperative day 11 without complications. Whole-body fluorine-18 fluorodeoxyglucose fusion positron emission tomography performed 2 months after surgery showed no signs of recurrence or metastasis. There was also no recurrence or metastasis at 24 months' follow-up.

[A case of colon obstruction developed during the recovery period of acute pancreatitis].

Complications of acute pancreatitis usually occur in pancreas and its contiguous organs. The prevalence of colonic invasion is rare, however, the consequence is fatal, with mortality above 50%. The initial symptoms and onset times are variable and major affected sites are transverse colon and splenic flexure. The spread of inflammatory exudates into the colon is the main mechanism of colonic invasion. If the colonic stenosis develops, it is necessary to manage it surgically. We report a case who arrived at the hospital with watery diarrhea and abdominal distension in the recovery period of acute alcoholic pancreatitis and was diagnosed as a colonic obstruction in the splenic flexure. The patient underwent loop ileostomy instead of the resection of the lesion because of severe adhesion around the splenic flexure. The patient died due to sepsis 5 days after the operation.

[Glutathione levels in Helicobacter pylori-infected gastric mucosa].

BACKGROUND/AIMS: Oxidative stress may contribute to gastric epithelial damage and mutagenesis caused by Helicobacter pylori (H. pylori). H. pylori induces recruitment and activation of inflammatory cells, which produces reactive oxygen species. H. pylori extract directly induces the synthesis of reactive oxygen species in gastric epithelial cells and causes DNA damage. The aim of this study was to investigate the association between the levels of glutathione (GSH) and H. pylori density, histological findings, endoscopic findings, clinical variables, and virulence factors. METHODS: Gastric biopsy specimens were obtained from 73 consecutive patients. The 5,5'-dithiobis-(2-nitrobenzoic acid) reaction was used to determine GSH levels. RESULTS: The infection rate of H. pylori was 68.5%. The GSH level was not related to age, sex, alcohol intake, and endoscopic findings. The GSH level was lower in patients infected with H. pylori. GSH levels were not correlated significantly with the grades of neutrophil, intestinal metaplasia, and atrophy. However, the GSH levels were significantly correlated with H. pylori density (r=-0.296, p=0.01) and monocyte grade (r=-0.257, p=0.02). The GSH levels were not related to CagA, VacA, and UreA. CONCLUSIONS: This study suggests that H. pylori causes oxidative stresses which deplete GSH in gastric mucosa of patients infected with H. pylori.

[Helicobacter pylori infection in the remnant stomach after radical subtotal gastrectomy].

BACKGROUND/AIMS: It was reported that the prevalence of Helicobacter pylori (H. pylori) infection decreased after gastrectomy, but persistent H. pylori infection may cause residual gastritis or stump cancer. We studied the prevalence of H. pylori infection in patients who had undergone subtotal gastrectomy for the treatment of gastric cancer and the factors that influence H. pylori positivity in the remnant stomach. METHODS: Ninety-eight patients who had undergone radical subtotal gastrectomy (RSG group) for the treatment of gastric cancer and eighty-four patients diagnosed as having gastric cancer (GC group) were enrolled. H. pylori status was diagnosed by rapid urease test, histological examination, and 13C-urea breath test. We evaluated whether there were differences in various clinical characteristics according to the H. pylori status in the remnant stomach. RESULTS: The prevalences of H. pylori infection in RSG group and GC group were 55% and 69%, respectively. In RSG group, the prevalence of H. pylori was 76.9% in patients aged 49 or less, and it decreased with age. The prevalence of H. pylori within 3 years of gastrectomy was 59.5% and it decreased to 28.6% after 3 years of gastrectomy. CONCLUSIONS: The positive rate of H. pylori in RSG group is lower than that in GC group and decreases with age and time interval after operation.

[Polymorphism in codons 10 and 25 of the transforming growth factor-beta1 gene in Korean population and in patients with liver cirrhosis and hepatocellular carcinoma].

BACKGROUND/AIMS: The genetic polymorphism of transforming growth factor-beta1 (TGF-beta1) at codons 10 and 25 which influences the production of TGF-beta1 is related to fibrogenesis in the lung and liver. We evaluated the genetic polymorphism at codons 10 and 25 in controls and in patients with liver cirrhosis (LC) and hepatocellular carcinoma (HCC). METHODS: Blood samples were collected from controls (n=35), patients with LC (n=64), and HCC (n=49). Genomic DNA was isolated and polymerase chain reaction (PCR) was done for a segment including codons 10 and 25. The results of direct sequencing for PCR products were compared between the controls and the patients. RESULTS: There was no genetic polymorphism at codon 25 and three types of genetic polymorphism at codon 10. The leucine homozygous genotype (CTG/CTG) at codon 10 was more common in patients with LC than the controls (p=0.01) and especially in patients with LC caused by HBV (p=0.004). The polymorphism at codons 10 in patients with HCC was similar to the controls. However, leucine homozygous genotype was more common in patients with HCC of uninodular morphology than those of massive morphology (p=0.007). CONCLUSIONS: The genetic polymorphism of TGF-beta1 at codon 10 might be associated with LC and morphology of HCC. The potential usefulness of TGF-beta1 genotyping needs further studies in large scale.

[Clinical usefulness of plasma activities of gelatinase (matrix metalloproteinase-2 and 9) in chronic liver disease].

BACKGROUND/AIMS: Gelatinase (matrix metalloproteinase (MMP) -2 and 9) has an important role in the pathogenesis of liver cirrhosis (LC) and hepatocellular carcinoma (HCC). In this study, we evaluated the relationship of gelatinase to chronic liver disease. METHODS: Four groups of subjects were examined; healthy control (10 cases), chronic hepatitis (18 cases), LC (15 cases), and HCC (28 cases). The plasma of each subject was obtained, and the equal quantification of plasma protein was done. The plasma activities of MMP-2 and 9 were measured by zymography. RESULTS: The activities of plasma MMP-2 in patients with LC were significantly higher than those in controls (p=0.009) and in patients with chronic hepatitis (p=0.011), but not different from those in patients with HCC. The activities of plasma MMP-9 in patients with LC were significantly higher than those in controls, but not different from those in patients with chronic hepatitis or HCC. In patients with LC (regardless of having HCC), the activities of MMP-2 correlated with total bilirubin (r=0.323, p=0.048) and Child-Pugh score (r=0.414, p=0.012). The activities of MMP-2 and 9 were higher in patients with LC (regardless of having HCC) caused by alcohol than caused by HBV (p=0.009 and 0.002 for each one). CONCLUSIONS: The plasma activity of MMP-2 may be a useful marker for the diagnosis and determination of the severity of LC. The plasma activity of MMP-9 was not useful for HCC, but may be a marker for alcoholic LC. Further study is needed to determine why the plasma activity of gelatinase was higher in patients with LC caused by alcohol than by HBV.

[Clinical and virologic characteristics of lamivudine resistance in HBV-associated chronic liver disease].

BACKGROUND/AIMS: Lamivudine therapy in chronic hepatitis B has been shown to be effective in inhibiting HBV replication. However, lamivudine resistance has been developed with prolonged use. We studied to determine the prevalence, predictive factors, and clinical outcomes of lamivudine resistance. Mutations in YMDD motif of HBV polymerase, which have been associated with lamivudine resistance, were also assessed. METHODS: 170 patients with HBV-associated chronic liver disease who have received lamivudine for at least one year, were studied. The clinical, biochemical, and virologic characteristics were analyzed and compared according to presence (resistance group) or absence (non-resistance group) of DNA breakthrough. Their clinical outcomes were regularly followed. Stored sera before treatment and after DNA breakthrough were examined for detection of HBV polymerase mutation by direct sequencing and/or RFLP. RESULTS: Cumulative rates of lamivudine resistance after one and two years of treatment were 11% and 34%, respectively. In the resistance group, as compared to the non-resistance group, age, the presence of HBeAg before treatment, and disappearance of HBeAg during treatment, were significantly different. The predictive factors associated with lamivudine resistance were not found. ALT and HBV-DNA level after lamivudine resistance was variable, but jaundice or hepatic failure was absent. Mutation in YMDD motif was detected in 73% and other variable mutations were detected before treatment and after DNA breakthrough. CONCLUSIONS: Lamivudine resistance increases the longer the duration of treatment and clinical outcomes are variable. The mutation in YMDD motif was found in about 2/3 of cases. Other causes for lamivudine resistance may be considered.