Optimal Methods for the Management of Iatrogenic Colonoscopic Perforation.

BACKGROUND/AIMS: Colonoscopic perforations have been managed with exploratory laparotomy, and have resulted in some morbidity and mortality. Recently, laparoscopic surgery is commonly performed for this purpose. The aim of this study was to compare the outcomes of several management strategies for iatrogenic colonoscopic perforations. METHODS: We retrospectively reviewed the medical records of patients who had been treated for colonoscopic perforation between January 2004 and April 2013 at CHA Bundang Medical Center in Korea. RESULTS: A total of 41 patients with colonoscopic perforation were enrolled. Twenty patients underwent conservative management with a success rate of 90%. Surgical management was performed in 23 patients including two patients who were converted to surgical management after the failure of the initial conservative management. Among 14 patients who underwent surgery at 8 hours after the perforation, there was no considerable difference in adverse outcomes between the laparotomy group and the laparoscopic surgery group. The medical costs and claim rate were 1.45 and 1.87 times greater in the exploratory laparotomy group, respectively. CONCLUSIONS: Conservative management of colonoscopic perforation could be an option for patients without overt symptoms of peritonitis or with a small defect size. If surgical management is required, laparoscopic surgery may be considered as the initial procedure even with a delayed diagnosis.

TWIST1 and SNAI1 as markers of poor prognosis in human colorectal cancer are associated with the expression of ALDH1 and TGF-ß1.

Epithelial-mesenchymal transition (EMT) is an important factor in cancer invasiveness and metastatic progression. During EMT, cancer cells acquire stem cell properties. The role of EMT and stemness in colon cancer has not been fully understood. We aimed to demonstrate the clinical significance of EMT and the stem cell phenotype in colorectal cancer. Two hundred and thirty-one surgically resected colon cancer cases were included in the present study. mRNAs of E-cadherin, TWIST1 and SNAI1 were analyzed by quantitative real-time polymerase chain reaction (qRT-PCR) (n=109). Immunohistochemical staining was performed for six markers (ALDH1, TGF-ß1, E-cadherin, ß-catenin, TWSIT1 and SNAI1) (n=231). We assessed clinicopathological characteristics according to the expression of the stem cell phenotype and EMT markers. Based on the results of qRT-PCR, TWIST1 and SNAI1 significantly influenced node metastasis (P=0.04 and P=0.02, respectively). High TWIST1 and SNAI1 mRNA expression was associated with poor overall survival according to the univariate analysis (P<0.01 and P=0.01, respectively) and the multivariate analysis (P=0.04 and P=0.04, respectively). ALDH1 expression as detected by immunohistochemical staining was associated with high nodal stage, advanced clinical stage, lymphatic invasion and poor survival (P=0.01, P=0.04, P<0.05 and P<0.01, respectively) and with the expression of TGF-ß1 and ß-catenin. In conclusion, in human colorectal cancer, the EMT markers TWIST1 and SNAI1 are suggested as important markers of poor prognosis. Their expression is associated with the expression of putative stem cell marker ALDH1, and ALDH1 is associated with the expression of TGF-ß1.

Polymorphisms of the pri-miR-34b/c promoter and TP53 codon 72 are associated with risk of colorectal cancer.

The microRNA (miR)-34 family is a direct transcriptional target of tumor-suppressor TP53 and loss of miR-34 function may impair TP53-mediated cell cycle arrest and apoptosis. In the present study, we investigated whether the single nucleotide polymorphisms (SNPs) rs4938723 (T>C) in the promoter region of miR-34b/c and Arg72Pro (G>C) in codon 72 of TP53 are independently or complementarily associated with the risks and clinical outcomes of colorectal cancer (CRC) and whether the combined effect of these SNPs and metabolic risk factors are related to CRC. We evaluated the SNPs in 545 CRC patients and 428 healthy controls using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and DNA sequence analysis. We found that the GC and GC/CC genotypes of TP53 Arg72Pro were associated with decreased risk of CRC (adjusted OR = 0.727 for GC; OR = 0.735 for GC/CC). The combined genotypes of TT-GC and CC-GG were significantly associated with reduced CRC risk (adjusted OR = 0.628 for TT-GC; OR = 0.381 for CC-GG, respectively). The SNP rs4938723 and diabetes mellitus (DM) together were associated with an increased CRC risk, but the SNP TP53 Arg72Pro CC with DM showed a protective effect against CRC. These findings indicate that rs4938723 in the promoter region of pri-miR-34b/c and the SNP in TP53 codon 72 were related to decreased risk of CRC in the population studied and those metabolic diseases and genetic variants influence each other with regard to CRC susceptibility.

Gastrointestinal cancers in a peutz-jeghers syndrome family: a case report.

A 17-year-old man was diagnosed as Peutz-Jeghers syndrome (PJS) because of pigmented lip and multiple gastrointestinal polyps. He had anemia and underwent polypectomy on the duodenum and colon. His maternal family members were patients with PJS. His mother used to be screened with endoscopy to remove large polyps. One and half years later, he underwent jejunal segmental resection due to intussusceptions. He underwent endoscopic polypectomy every 2 to 3 years. When he was 23 years old, high-grade dysplasia was found in colonic polyp and his mother underwent partial pancreatectomy due to intraductal papillary mucinous carcinoma. When he was 27 years old, diffuse gastric polyps on the greater curvature of corpus expanded and grew. Therefore, wide endoscopic polypectomy was done. Histological examination revealed focal intramucosal carcinoma and low-grade dysplasia in hamartomatous polyps. We report cases of cancers occurred in first-degree relatives with PJS.

Endoscopic resection of giant colonic lipoma: case series with partial resection.

Colonic lipoma, a very rare form of benign tumor, is typically detected incidentally in asymptomatic patients. The size of lipoma is reported variously from 2 mm to 30 cm, with higher likelihood of symptoms as the size is bigger. Cases with symptom or bigger lesion are surgically resected in principle; endoscopic resection, which has developed recently with groundbreaking advance of endoscopic excision technology, is being used more often but with rare report of success due to high chance of complications such as bowel perforation or bleeding. The authors report here, together with a literature review, our experiences of three cases of giant colonic lipomas showing complete remission after aggressive unroofing technique, at certain intervals, using snare catheter at the origin of the lipoma so that the remaining lipoma could be drained out of the exposed surface spontaneously, in order to reduce complications.

Endoscopic treatment of refractory gastroesohageal reflux disease.

Though efficient acid suppression with proton pump inhibitors (PPIs) remains the mainstay of treatment of gastroesophageal reflux disease (GERD), some of the patients showed refractory response to PPIs, necessitating further intervention. After increasing dose of PPIs and other kinds of pharmacological intervention adopting prokinetics or others, variable endoscopic treatments are introduced for the treatment of these refractory cases. The detailed introduction regarding endoscopic treatment for GERD is forwarded in this review article. Implantation of reabsorbable or synthetic materials in the distal esophagus was tried in vain and is expelled from the market due to limited efficacy and serious complication. Radiofrequency energy delivery (Stretta) and transoral incisionless fundoplication (EsophyX) are actively tried currently.

Promoter polymorphisms of pri-miR-34b/c are associated with hepatocellular carcinoma.

BACKGROUND: Numerous studies have focused on the association between miR-34 family members, which are direct p53 targets, and carcinogenesis of many cancers, including hepatocellular carcinoma (HCC). This study aimed to assess whether polymorphisms in the single-nucleotide polymorphism miR-34b/c T>C (rs4938723) and TP53 Arg72Pro (rs1042522) increase the risk of HCC and influence outcome in patients with HCC. PATIENTS AND METHODS: We enrolled 157 HCC patients and 201 cancer-free control subjects from the Korean population. MicroRNA polymorphisms were genotyped using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. RESULTS: We found that the miR-34b/c TC+CC frequency was significantly higher in HCC patients than in controls (adjusted odds ratio [AOR]: 1.580; 95% confidence interval [CI]: 1.029-2.426). The miR-34b/c CC-TP53 Arg/Arg combination significantly increased the risk of HCC (AOR: 13.644; 95% CI: 1.451-128.301). The SNPs miR-34b/c T>C and TP53 Arg72Pro(G>C) had no influence on survival of HCC patients. CONCLUSIONS: Our findings suggest that loss of the T allele in miR-34b/c T>C, and the miR-34b/c CC-TP53 Arg/Arg combination increases the risk of HCC in the Korean population.

Prevalence of occult hepatitis B virus infection in hemodialysis patients.

BACKGROUND/AIMS: The prevalence of occult HBV infection depends on the prevalence of HBV infection in the general population. Hemodialysis patients are at increased risk for HBV infection. The aim of this study was to determine the prevalence of occult HBV infection in hemodialysis patients. METHODS: Total of 98 patients undergoing hemodialysis in CHA Bundang Medical Center (Seongnam, Korea) were included. Liver function tests and analysis of HBsAg, anti-HBs, anti-HBc and anti-HCV were performed. HBV DNA testing was conducted by using two specific quantitative methods. RESULTS: HBsAg was detected in 4 of 98 patients (4.1%), and they were excluded. Among 94 patients with HBsAg negative and anti-HCV negative, one (1.1%) patient with the TaqMan PCR test and 3 (3.2%) patients with the COBAS Amplicor HBV test were positive for HBV DNA. One patient was positive in both methods. Two patients were positive for both anti-HBs and anti-HBc and one patient was negative for both anti-HBs and anti-HBc. CONCLUSIONS: The present study showed the prevalence of occult HBV infection in HBsAg negative and anti-HCV negative patients on hemodialysis at our center was 3.2%. Because there is possibility of HBV transmission in HBsAg negative patients on hemodialysis, more attention should be given to prevent HBV transmission.

[Effect of proton pump inhibitor in patients with acute pancreatitis - pilot study].

BACKGROUND/AIMS: Oxygen free radicals play an important role in acute pancreatitis. Pantoprazole as a proton pump inhibitor (PPI) has pancreatic anti-secretory effect and a pronounced inhibitory reactivity towards hydroxyl radicals. The objective of the study was to investigate the effect of pantoprazole on the course of acute pancreatitis. METHODS: We conducted a prospective randomized trial involving 40 patients with acute pancreatitis. Patients were divided into two groups. One group received PPI and the other group did not receive PPI. In the PPI group, patients received pantoprazole 40 mg intravenously twice a day for fasting time, and then 40 mg orally twice a day until discharge. RESULTS: There were no significant differences in baseline characteristics and laboratory markers between two groups. In the pantoprazole group, mean hospital stay was 7.4 days, time to start oral intake was 69.0 hours, and time to pain relief was 59.7 hours. Acute physiology and chronic health evaluation (APACHE) II score was 3.15 at admission day and 2.35 at discharge. On the other hand, in the non-pantoprazole group, mean hospital stay was 7.6 days, time taken to start oral intake was 71.4 hours, and time taken to pain relief was 61.8 hours. APACHE II score was 4.4 at admission and 2.85 at discharge. However, there were no significant differences between two groups. CONCLUSIONS: Treatment with pantoprazole did not have influence on the clinical course of acute pancreatitis. But, considering it was a pilot study, large scale prospective trials will be needed.

Rifaximin Plus Levofloxacin-Based Rescue Regimen for the Eradication of Helicobacter pylori.

BACKGROUND/AIMS: This study assessed the efficacy of a rifaximin plus levofloxacin-based rescue regimen in patients that had failed both triple and quadruple standard regimens for the eradication of Helicobacter pylori. METHODS: We treated patients for H. pylori between August 2009 and April 2011. The triple regimen consisted of combined treatment with amoxicillin, clarithromycin, and pantoprazole for 1 week. For failed cases, a quadruple regimen of tetracycline, metronidazole, bismuth dicitrate, and lansoprazole for 1 week was administered. The rescue regimen for persistently refractory cases was rifaximin 200 mg t.i.d., levofloxacin 500 mg q.d., and lansoprazole 15 mg b.i.d. for 1 week. RESULTS: In total, 482 patients were enrolled in this study. The eradication rates associated with the first and second regimens were 58% and 60%, respectively. Forty-seven out of 58 patients who failed with the second-line regimen received rifaximin plus levofloxacin-based third-line therapy. The eradication rate for the third regimen was 65%. The cumulative eradication rates were 58%, 85%, and 96% for each regimen, respectively. CONCLUSIONS: A rifaximin plus levofloxacin-based regimen could be an alternative rescue therapy in patients with resistance to both triple and quadruple regimens for the eradication of H. pylori.

An impacted pancreatic stone in the papilla induced acute obstructive cholangitis in a patient with chronic pancreatitis.

Obstructive jaundice is very rarely caused by impaction of a pancreatic stone in the papilla. We report here on a case of obstructive jaundice with acute cholangitis that was caused by an impacted pancreatic stone in the papilla in a patient with chronic pancreatitis. A 48-year-old man presented with acute obstructive cholangitis. Abdominal computed tomography with the reconstructed image revealed distal biliary obstruction that was caused by a pancreatic stone in the pancreatic head, and there was also pancreatic ductal dilatation and parenchymal atrophy of the pancreatic body and tail with multiple calcifications. Emergency duodenoscopy revealed an impacted pancreatic stone in the papilla. Precut papillotomy using a needle knife was performed, followed by removal of the pancreatic stone using grasping forceps. After additional sphincterotomy, a large amount of dark-greenish bile juice gushed out. The patient rapidly improved and he has remained well.

Association study of microRNA polymorphisms with hepatocellular carcinoma in Korean population.

BACKGROUND: Recent studies have suggested that common genetic polymorphisms alter the processing of microRNA (miRNA) and may be associated with the development and progression of cancer. PATIENTS AND METHODS: The association of miRNA polymorphisms with HCC survival was analyzed in 159 HCC patients and 201 controls by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. RESULTS: The risk of HCC was significantly lower for the miR-499A>G, AG+GG in HCC patients (AOR=0.603, 95% CI=0.370-0.984) and hepatitis B virus (HBV)-related HCC patients (AOR=0.561, 95% CI 0.331-0.950). In addition, the risk of HCC was significantly lower for the miR-149C>T, CT and CT+CC in HCC patients (CT; AOR=0.542, 95% CI=0.332-0.886, CT+CC; AOR=0.536, 95% CI=0.335-0.858) and HBV-related HCC patients (CT: AOR=0.510, 95% CI 0.305-0.854, CT+CC: AOR=0.496, 95% CI 0.302-0.813). The miR-149C>T polymorphism was also associated with survival rate of HCC patients in OKUDA II stage. CONCLUSIONS: miR-149C>T and miR-499A>G were associated with HBV-related HCC. Further studies on larger populations will need to be conducted to confirm these results.

The role of 18F-FDG PET/CT in the evaluation of gastric cancer recurrence after curative gastrectomy.

PURPOSE: (18)F-fluorodeoxyglucose positron emission tomography/computed tomography ((18)F-FDG PET/CT) scans are frequently performed for the screening or staging of malignant tumors. This study aimed to assess the usefulness of (18)F-FDG PET/CT in detection of gastric cancer recurrence after curative gastrectomy. MATERIALS AND METHODS: Eighty nine patients who had undergone curative gastrectomy due to gastric cancer and had (18)F-FDG PET/CT and contrast CT scans within 2 weeks for surveillance in asymptomatic patients (n = 11) or to clarify suspected recurrence (n = 78) were consecutively collected and retrospectively analyzed. They had clinical follow-up for at least 12 months after PET/CT and CT scans. RESULTS: Fifteen of the 89 patients (16.9%) were diagnosed with recurrent gastric cancer in 21 organs. Forty one organs showed an increase in FDG uptake, and only 9 of these organs were diagnosed with recurrent gastric cancer by (18)F-FDG PET/CT. The sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of the (18)F-FDG PET/CT were 42.9%, 59.7%, 29.3%, 78.2%, and 57.3%, respectively. On the CT scan, 18 of 21 recurrent gastric cancers were detected, and 7 cases were in agreement with the (18)F-FDG PET/CT. The sensitivity and specificity of the CT scan were 85.8% and 87.3%, respectively, which are superior to the (18)F-FDG PET/CT. When we diagnosed a recurrence based on either (18)F-FDG PET/CT or CT scans, the sensitivity increased to 95.2% and the specificity decreased to 45.6%, when compared with the contrast CT scan alone. CONCLUSION: (18)F-FDG PET/CT is an insufficient diagnostic method in detection of recurrence after curative gastrectomy, and even less accurate than contrast CT scan alone.

Colonoscopic clipping as a treatment for appendiceal bleeding.

Bleeding from the appendix has been reported very rarely in patients with lower-gastrointestinal-tract bleeding. In general, after a colonoscopic diagnosis of appendiceal bleeding, laparoscopic or surgical appendectomy would be recommended. Two patients with continuous bleeding from the appendix were treated with partial occlusion of the appendiceal orifice by colonoscopic clipping. In neither case was there evidence of further active bleeding over the following 12 months. This is the first report of such a treatment in the English literature.

Fatal biliary-systemic air embolism during endoscopic retrograde cholangiopancreatography: a case with multifocal liver abscesses and choledochoduodenostomy.

We report a rare case of a massive fatal embolism that occurred in the middle of endoscopic retrograde cholangiopancreatography (ERCP) and retrospectively examine the significant causes of the event. The patient was a 50-year old female with an uncertain history of previous abdominal surgery for multiple biliary stones 20 years prior. The patient presented with acute right upper quadrant pain. An abdominal computed tomographic (CT) scan revealed the presence of multiple stones in the common bile duct (CBD) and intra-hepatic duct (IHD) with biliary obstruction, multifocal liver abscesses, and air-biliarygram. Emergency ERCP showed a wide and straight opening of choledochoduodenostomy, which may have been created during a previous surgery, and multiple filling defects in the CBD. With the use of a forward endoscope, mud stones were extracted through the opening of the choledochoduodenostomy. Cardiac arrest suddenly developed during the procedure, and despite immediate resuscitation, the patient died due to a massive systemic air embolism. We reviewed previously reported fatal cases and accessed factors facilitating air embolisms in this case.

Bowel obstruction caused by an intramural duodenal hematoma: a case report of endoscopic incision and drainage.

Complications associated with an intramural hematoma of the bowel, is a relatively unusual condition. Most intramural hematomas resolve spontaneously with conservative treatment and the patient prognosis is good. However, if the symptoms are not resolved or the condition persists, surgical intervention may be necessary. Here we describe internal incision and drainage by endoscopy for the treatment of an intramural hematoma of the duodenum. A 63-yr-old woman was admitted to the hospital with hematemesis. The esophagogastroduodenoscopy (EGD) showed active ulcer bleeding at the distal portion of duodenal bulb. A total of 10 mL of 0.2% epinephrine and 2 mL of fibrin glue were injected locally. The patient developed diffuse abdominal pain and projectile vomiting three days after the endoscopic treatment. An abdominal computed tomography revealed a very large hematoma at the lateral duodenal wall, approximately 10 x 5 cm in diameter. Follow-up EGD was performed showing complete luminal obstruction at the second portion of the duodenum caused by an intramural hematoma. The patient's condition was not improved with conservative treatment. Therefore, 21 days after admission, endoscopic treatment of the hematoma was attempted. Puncture and incision were performed with an electrical needle knife. Two days after the procedure, the patient was tolerating a soft diet without complaints of abdominal pain or vomiting. The hematoma resolved completely on the follow-up studies.

STAT3 expression in gastric cancer indicates a poor prognosis.

BACKGROUND AND AIM: Signal transducers and activators of transcription (STAT) behave as signal transducers in the cytoplasm and as transcription factors in the nucleus. In the current study, we analyzed the immunohistochemical staining patterns of gastrectomy tissue specimens. We investigated the expression of STAT3 and STAT5 and estimated the relationship between STAT and cancer prognosis. METHODS: One hundred patients who underwent gastrectomy due to gastric adenocarcinoma at Bundang CHA hospital between January 2000 and May 2005 were studied. Immunohistochemistry was carried out using antibodies against STAT3 and STAT5. The interpretation of the immunohistochemical staining was based on the proportion of stained cells in the field: positive, > 10% stained cells; and negative, < 10% stained cells. RESULTS: The longest diameter of tumor was 4.67 cm in the positive group and 3.76 cm in the negative group, and these results were not statistically different (P-value = 0.112). Higher T (primary tumor) value (P-value = 0.05), more regional lymph node invasion (P-value = 0.008) and higher TNM staging (P-value = 0.069) were significantly related to STAT3 positivity, but Helicobacter pylori infection or atrophic gastritis were not related. A lower survival rate was observed in the STAT3-positive group (P-value = 0.001). The results of STAT5 were not statistically different with respect to TNM staging and survival (P-value = 0.958). We thus report that the immunohistochemical results of STAT3 revealed a significant association with TNM staging and survival. CONCLUSION: We anticipate that STAT3 may be used as a molecular staging biomarker predicting poor prognosis of gastric cancer.

[Clinical characteristics of health screen examinees with nonalcoholic fatty liver and normal liver function test].

BACKGROUND/AIMS: Nonalcoholic fatty liver disease (NAFLD) is known to be closely associated with various metabolic abnormalities including metabolic syndrome. However, there are few data available on the association of metabolic syndrome with the sonographically fatty liver and normal range of liver function test. The purposes of this study were to find the incidence of ultrasonographic fatty liver with normal range of liver function test and to evaluate the association with metabolic syndrome in apparently healthy Korean adults. METHODS: We examined 538 men and women, aged 30-80 years, who participated in a health screening test. Among the people with normal ALT level, we compared clinical characteristics and prevalence of metabolic disorders according to the presence of nonalcoholic sonographyally fatty liver, and then they were subdivided into upper normal range and lower normal range of ALT level. RESULTS: Compared to the people without sonographic fatty liver, people with sonographic fatty liver and normal range of ALT level had odds ratios for metabolic syndrome of 4.53, insulin resistance 4.83, hypertension 2.69, dyslipidemia 6.90, and obesity 5.39, respectively. Furthermore, the prevalence of metabolic syndromes and other metabolic disorders were increased in both sonographically fatty liver group or ultrasonographically normal liver group with upper normal range of ALT level compared with lower normal ALT level (p<0.01). CONCLUSIONS: The nonalcoholic sonographically fatty liver was strongly associated with metabolic syndrome and common metabolic abnormalities even with normal liver function test.

[Hepatitis B core antigen expression pattern predicts response to lamivudine therapy in patients with chronic hepatitis B].

BACKGROUNDS/AIMS: Negative hepatitis B core antigen (HBcAg) staining in hepatocytes is indicative of viral replication by an active immune response. HBcAg is expressed mainly in the cytoplasm in patients with active hepatitis and hepatocyte regeneration, and mainly in the nuclei of hepatocytes in patients with minimal liver injury in the absence of hepatocyte regeneration. The aim of this study was to elucidate whether the existence and expression pattern of HBcAg predicts the response to antiviral treatment. METHODS: The study involved 58 patients with biopsy-proven chronic hepatitis B who were treated with lamivudine. Hepatitis B e antigen (HBeAg), antibody to HBeAg, hepatitis B virus DNA, and alanine aminotransferase in serum were recorded every 3 months. The inflammation grade and the fibrosis stage of chronic hepatitis were scored from 0 to 4 according to lobular inflammation, portal inflammation, periportal inflammation, and fibrosis. RESULTS: The 58 patients included 49(84%) HBcAg-positive patients, with HBcAg staining confined to the cytoplasm in 15(31%) and in both cytoplasm and nuclei in 34(69%). The grade of lobular inflammation and the total histology score were significantly higher in patients with cytoplasmic expression of HBcAg than in HBcAg-negative patients (lobular inflammation: 2.9 vs 2.1, P=0.02; total histology score: 12.2 vs 10.3, P=0.04). The virologic responses at 3, 6, 9, and 12 months differed significantly between the cytoplasmic and mixed expression groups (P<0.01). CONCLUSIONS: The expression pattern of HBcAg (including its possible absence) before initial therapy appears to predict the response to antiviral treatment.

Occult hepatitis B virus infection in pregnant woman and its clinical implication.

BACKGROUND/AIMS: The objective of this study was to document the prevalence rate of occult hepatitis B virus (HBV) in healthy pregnant woman and the possibility of transmission to the foetus. METHODS: This study was performed prospectively with 202 healthy pregnant women. HBV-DNA testing was performed using two specific quantitative tests with two independent sets of sera and cord blood. DNA sequencing analysis was carried out to confirm the specificity of polymerase chain reaction (PCR) product of HBV-DNA testing. RESULTS: Eight of 202 (4%) individuals with the TaqMan PCR assay and 23 of 202 (11.4%) with the COBAS Amplicor HBV Monitor test were HBV-DNA positive. Six (3%) individuals were positive with both methods. Sequencing and genotyping analysis of HBV polymerase gene with sera of the 75th subject resulted in genotype C. HBV-DNA testing with four cord blood samples showed that all were HBV-DNA negative. CONCLUSION: Occult HBV infection shows a difference in prevalence rate depending on the test method but the existence has been confirmed by sequencing analysis. Our results also suggest that vertical transmission through the cord blood is not so high as to be clinical problems and warrants further investigation.