Standard triple therapy in Helicobacter pylori eradication in Turkey: Systematic evaluation and meta-analysis of 10-year studies

BACKGROUND/AIMS

This study aims at evaluating the mean eradication rate by a systematic compilation of the studies which involved the standard triple therapy (STT) in first-line Helicobacter pylori (Hp) eradication in Turkey over a period of 10 years between 2004 and 2013 using the meta-analysis method.

MATERIALS AND METHODS

The systematic compilation and meta-analysis were carried out according to the PRISMA standards defined in the Cochrane handbook. The results of full-text studies published in national and international journals in English and Turkish languages on Turkish population in a period of 10 years, from 2004 to 2013, are included in this study. The studies include open-label trials, controlled trials, treatment arms, and case series that included a triple therapy regimen consisting of standard doses of a proton pump inhibitor (PPI; omeprazole 20 mg BID, lansoprazole 30 mg BID, pantoprazole 40 mg BID, esomeprazole 40 mg BID, or rabeprazole 20 mg BID) along with clarithromycin 500 mg BID and amoxicillin 1 g BID for 7-14 days. They were scanned electronically via the search engines Google Scholar, PubMed, and the Turkish Medicine Index using specific keywords. The related keywords used were Turkey, Helicobacter pylori, infection, standard triple treatment, first-line therapy, eradication, omeprazole, lansoprazole, pantoprazole, rabeprazole, esomeprazole, clarithromycin, and amoxicillin. Studies carried out with adults were included in the evaluation. The publication year of the studies and the included number of patients, their age, gender, treatment duration (7, 10, and 14 days), and PPIs used were evaluated by two separate gastroenterologists and biostatisticians. Studies that used at least one reliable method (histology, urea breath test (UBT), or Helicobacter pylori stool antigen (HpSA) test) four weeks after completing the treatment for the control of Hp eradication were included. Only naive patients were accepted, and patients who had previously received eradication treatment were excluded. The effectiveness of the Hp eradication was analyzed using an intention-to-treat (ITT) or per-protocol (PP) analysis.

RESULTS

The STT regime of 45 studies complying with the inclusion criteria was evaluated. A total of 3715 patients were included in the study. Of the 3010 patients whose gender information was available, 55% were women and 45% were men; the weighted age average given explicitly in the studies was 42.14±0.67. The treatment lasted for 14 days in 42 studies, for 7 days in six studies, and for 10 days in 1 study. The eradication rates evaluated according to the ITT and PP analyses were 60% (95% CI: 56%-63%) and 57% (95% CI: 51%-62%), respectively. The rates for 7 days of treatment were 57% (95% CI: 46%-68%) and 60% (95% CI: 51%-67%) and for 14 days of treatment were 60% (95% CI: 56%-63%) and 56% (95% CI: 50%-62%), respectively. The ITT eradication rate of the only 10-day study was 78% (95% CI: 66%-86%). In the meta-regression analysis, the treatment duration, PPI, age, and gender ratio (women/men) used for the ITT analysis had no effect. The gender ratio and age were not considered in this analysis because they were not clearly stated in studies using the PP analysis. The duration of treatment and the PPI used had no effect.

CONCLUSION

A systematic meta-analysis of studies conducted during the period 2004-2013 in Turkey revealed that the rate of first-line Hp eradication using STT was unacceptably low, and the duration of treatment and PPI used made no difference.

Real-life results of treatment with ombitasvir, paritaprevir, dasabuvir, and ritonavir combination in patients with chronic renal failure infected with HCV in Turkey

BACKGROUND/AIMS

As the most common liver disease in hemodialysis patients, chronic hepatitis C (CHC) can cause cirrhosis and hepatocellular carcinoma, even increase in renal-related mortality. In Turkey, the frequency of anti-hepatitis C virus (HCV) antibodies in hemodialysis patients ranged from 31.4% to 51%. Until recently, the mainstay of the CHC treatment for these patients was pegylated interferon with potential toxicities and low sustained virological response. The 3D regimen, a combination of four drugs (ombitasvir, paritaprevir, dasabuvir, and ritonavir), has recently been used for patients with chronic kidney disease infected with genotype 1a and 1b HCV. The aim of the present study was to present results of 3D treatment for patients with hemodialysis-dependent chronic renal failure (CRF) who were chronically infected with HCV.

MATERIALS AND METHODS

Overall, 25 patients with hemodialysis-dependent CRF who were infected with genotype 1a/1b HCV have been treated using the 3D regimen in our gastroenterology clinic between July 2016 and October 2017. Three patients were administered additional ribavirin 200 mg/day. Serum HCV RNAs, blood chemistry, blood count, and side effects were recorded at 0, 4, and 12 weeks.

RESULTS

All 25 patients completed and well tolerated their planned treatment. At the end of 4 weeks, the viral response (defined as HCV RNA clearance) rate was 92%. At the end of 12 weeks of treatment and 3 months after treatment, viral response rates were both 100%.

CONCLUSION

We observed that the treatment with 3D regimen in hemodialysis patients infected with genotype 1 hepatitis C is highly effective and well tolerated.

Evaluation of hypertriglyceridemia-induced acute pancreatitis: A single tertiary care unit experience from Turkey

BACKGROUND/AIMS

This study aimed to determine the frequency of hypertriglyceridemia (HTG)-induced acute pancreatitis (AP) and assess different clinical and prognostic features in these patients.

MATERIALS AND METHODS

The patients who were hospitalized with AP due to HTG (HTG-AP) between January 2005 and December 2014 were retrospectively evaluated in the clinic. The patients with AP due to non-HTG (non-HTG-AP) were also investigated during the same period.

RESULTS

Of 635 patients with AP admitted to the clinic, 33 (5.2%) had HTG-related AP. Mean triglyceride levels were 2653 mg/dL (range: 439-13700 mg/dL). Mean Ranson score at the time of admission was 1.5, and the APACHE II score was 4.63. The mean duration of hospitalization was 4.4 days (range: 2-14 days). One of these patients died on the sixth day of hospitalization due to multiple-organ failure. Patients with a triglyceride level of >1000 mg/dL were younger, had a longer hospital stay, and had a higher recurrence rate. Compared with non-HTG-AP, HTG-AP was observed at a younger age (57.4±17.3 vs. 37.6±14.8, p<0.05, respectively) and more frequently in males (45.2% vs. 57.6%, p<0.05, respectively). The frequency of multiple AP in patients with HTG-AP was higher than non-HTG-AP (63.4% vs. 7.6%, respectively).

CONCLUSION

HTG-AP was observed at a younger age and was responsible for most cases of recurrent pancreatitis. The duration of hospitalization was long, and the risk of recurrence and mortality were high in patients with HTG-AP having a triglyceride level >1000 mg/dL.

Patients Lost after Anti-HCV-Positive Finding in a Tertiary Care University Hospital: Increased Awareness and Action is Necessary to Eradicate HCV

OBJECTIVES

Though there is a global effort to eradicate hepatitis C infection (HCV), several obstacles remain. Many patients infected with the virus are not detected or go untreated. The goal of this study was to identify any barriers to treatment and any difficulties contributing to the elimination of HCV infection at a tertiary care university hospital.

METHODS

This was a retrospective review. The hospital data system was searched for records of patients admitted to the hospital for any reason from between 2013 and 2018 who were screened for viral markers and determined to be anti-HCV positive. The follow-up performed was then analyzed.

RESULTS

Viral marker testing was requested for 65,853 patients during the study period. Of those, 64.735 (98.3%) were found to be anti-HCV negative and 1118 (1.7%) were anti-HCV positive. In all, 392 (35.06%) were detected in the gastroenterology department, 417 (37.3%) were patients in the infectious diseases department, and 309 (27.64%) were identified in other clinics, including emergency services, the blood bank, and others. There were 30/392 (7.65%) patients admitted to the gastroenterology clinic who declined a biopsy and/or treatment. In other clinics, 88/309 (28.5%) patients were identified who were not treated for HCV and not followed up because they were not referred to the related specialty department.

CONCLUSION

It was determined that there was a significant gap in referring patients to the appropriate specialized department following an anti-HCV positive finding and thus to appropriate follow-up and treatment programs.

[Determination of reverse transcriptase inhibitor nucleoside analogue resistance profile in pretreatment phase of patients with viral hepatitis B]

HBV is a DNA virus and the causative agent of hepatitis B infection. Hepatitis B is a contagious disease and is still a major health problem all over the world. When the infection become chronic, it may cause serious diseases such as fibrosis, cirrhosis and/or hepatocellular carcinoma. Interferon/pegylated interferon by intravenous route and nucleoside/nucleotide (NA) analogues such as lamivudine, adefovir, entecavir, telbivudine and tenofovir given by oral route are used in the treatment. Antivirals given by oral route are mostly preferred in the treatment. However, because of the replication strategy and biological properties of HBV, mutations that cause antiviral resistance against these drugs can occur at different rates, although they can vary from drug to drug over time. It is possible that drug resistant virus may transmit from patient to healthy individuals. Therefore, there is a possibility of infection with drug-resistant HBV before treatment. Antiviral resistance mutations are divided into four categories; i) Nucleos(t)ide analog resistance (NAr)-related mutations, ii) primary drug resistance mutations, iii) secondary/compensatory mutations, iv) putative antiviral resistance mutations and pre-treatment variations. Recent studies have focused particularly on putative mutations and pre-treatment variations. The aim of this study was to better understanding of the antiviral resistance profiles of chronic hepatitis B (CHB) patients treated and untreated with NA, and help to prevent unnecessary drug use, minimize the side effects and economic damages. A total of 124 patients who have received nucleoside analog (NA) drug treatments (n= 72) and patients without NA treatment (n= 52) were included in the study. Viral DNA was isolated from the plasma samples of the patients. A DNA fragment, which is 551 bp, was amplified and sequenced including the binding side of all nucleoside analogs containing the B, C and D domains located in the reverse transcriptase region in the HBV genome. Different types of mutations were detected in 13 (18.05%) of 72 treated patients and in 18 (34.61%) of 52 untreated patients (p< 0.05). Primary drug resistance mutations such as rtI169T, rtA181T/V, rtT184A/C/F/G/I/L/M/S, rtA194T, rtS202C/G/I, rtM204I/V/S, rtN236T, rt M250I/L/V and rtV173L were not detected in any of the patient samples. However, potential drug resistance mutations such as rtR164R, rtG165D/A, rtG172Q, rtS176N, rtF178V, rtA181G, rtS185N/G/C, rtV207M, rtQ215H/S, rtL231V, rtI233K, rtN238S, rtV253T, rtC256G/S and rtI266R/V were detected in untreated patient samples in B, C, D and D domains of reverse transcriptase region. Our results have suggested that the detection of pretreatment variations could be helpful for choosing the correct antiviral drug for the better treatment management.

Harnessing Knowledge on Very Important Pharmacogenes CYP2C9 and CYP2C19 Variation for Precision Medicine in Resource-Limited Global Conflict Zones

Pharmacogenomics harnesses the utility of a patient's genome (n = 1) in decisions on which therapeutic drugs and in what amounts should be administered. Often, patients with shared ancestry present with comparable genetic profiles that predict drug response. However, populations are not static, thus, often, population mobility through migration, especially enmasse as is seen for refugees, changes the pharmacogenetic profiles of resultant populations and therefore observed responses to commonly used therapeutic drugs. For example, in the aftermath of the Syrian civil war since 2011, millions have fled their homes to neighboring countries in the Middle East. The growing permanence of refugees and mass migrations is a call to shift our focus in the life sciences community from old models of pharmaceutical innovation. These seismic social changes demand faster decisions for "population-to-population bridging," whereby novel drugs developed in or for particular regions/countries can meet with rational regulatory decisions/approval in world regions impacted by migrant/refugee populations whose profiles are dynamic, such as in the Eastern Mediterranean region at present. Thus, it is important to characterize and report on the prevalence of pharmacogenes that affect commonly used medications and predict if population changes may call for attention to particular differences that may impact health of patients. Thus, we report here on four single-nucleotide polymorphism (SNP) variations in CYP2C9 and CYP2C19 genes among Mersin-Turkish healthy volunteers in the Mersin Province in the Eastern Mediterranean region that is currently hosting a vast number of migrant populations from Syria. Both CYP2C9 and CYP2C19 are very important pharmacogene molecular targets. We compare and report here on the observed SNP genetic variation in our sample with data on 12 world populations from dbSNP and discuss the feasibility of forecasting the pharmacokinetics of drugs utilized by migrant communities in Mersin and the Eastern Mediterranean region. This study can serve as a catalyst to invest in research in Syrian populations currently living in the Eastern Mediterranean. The findings have salience for rapid and rational regulatory decision-making for worldwide precision medicine and, specifically, "pharmacogenovigilance-guided bridging of pharmacokinetics" across world populations in the current era of planetary scale migration.

Effectiveness of Sedoanalgesia in Percutaneous Liver Biopsy Premedication

Aim:

Percutaneous needle liver biopsy (PLB) is frequently associated with pain and anxiety. This may discourage the patients for biopsy, and rebiopsies, if needed. We planned a study to investigate the efficacy of additional analgesia or sedation for PLB.

Materials and methods:

The study has been designed as a single-center, prospective study. The PLB was planned for 18- to 65-year-old consecutive patients who were included in the study. The patients were divided into three premedication groups as control, Meperidine, and Midazolam. Hospital Anxiety and Depression Scale (HADS) was used to measure each subject’s anxiety level. Fifteen minutes before the biopsy, 1 mL 0.9% NaCl subcutaneously (sc), 1 mg/kg (max 100 mg) Meperidine sc, or 0.1 mg/kg (max 5 mg) Midazolam intravenously was administered to patients respectively. Then PLB was done with 16 G Menghini needle. The day after, the patients were asked about feelings regarding biopsy.

Results:

Groups were similar by gender and age. The HADS scores prior to PLB and on visual analog scale (VAS, 1-10 points) score during PLB were similar. In the three groups, 7, 12, and 7 patients, respectively, experienced no pain. Other patients explained pain as mild or moderate or severe. The number of patients who agreed for possible rebiopsy was higher in Meperidine and Midazolam groups than in the control group.

Conclusion:

Premedication with Meperidine or Midazolam in PLB would improve patients’ tolerance, comfort, and attitude against a possible repeat PLB.

How to cite this article: Sezgin O, Yaras S, Ates F, Altintas E, Saritas B. Effectiveness of Sedoanalgesia in Percutaneous Liver Biopsy Premedication. Euroasian J Hepato-Gastroenterol 2017;7(2):146-149.

Distribution of hepatitis C virus genotypes among intravenous drug users in the Çukurova region of Turkey

BACKGROUND/AIM

The most common hepatitis C virus (HCV) genotype in Turkey is genotype 1. However, there has not been a study about the distribution of HCV genotypes among intravenous drug users (IVDUs) in the Çukurova region of Turkey. This study was planned to understand if there is a difference between IVDUs and the normal population.

MATERIALS AND METHODS

Between May 2010 and May 2014, anti-HCV positive IVDUs who applied to the 6 hospitals in the Çukurova region of Turkey were included in this study. Their HCV genotypes were studied.

RESULTS

Ninety-seven anti-HCV positive IVDUs were screened in terms of HCV RNA and genotype. Ten were excluded from the study because their HCV RNA results were negative. Fifty-one of the 87 patients (58.6%) had genotype 3. Genotype 2 was detected in 26 (29.9%) and genotype 1 was detected in 10 (11.5%) patients.

CONCLUSION

HCV genotypes seem to be different between the normal population and IVDUs according to studies worldwide. Among IVDUs, we detected a dominance of genotype 3 and genotype 2, which is apparently different from the normal population. The reason for this difference can be simply explained by infection through shared needles. However, there may still be a different immunological response in IVDUs, the investigation of which may lead to further studies.

Validity of modified early warning, Glasgow Blatchford, and pre-endoscopic Rockall scores in predicting prognosis of patients presenting to emergency department with upper gastrointestinal bleeding

Background

GBS, MEWS, and PER scoring systems are not commonly used for patients presenting to emergency department with GIS bleeding. This study aimed to determine the value of MEWS, GBS, and PER scores in predicting bleeding at follow-up, endoscopic therapy and blood transfusion need, mortality, and rebleeding within a 1-month period.

Methods

A total of 202 consecutive patients with upper GIS bleeding between July 2013 and November 2014 were prospectively enrolled in the study. The relationship between MEWS, GBS, and PER scores and hospital outcome, bleeding at follow-up, endoscopic therapy, transfusion need, rebleeding, and death were examined.

Results

The study included a total of 202 subjects, with 84 (41.6 %) females and 118 (58.4 %) males. There was a significant correlation between GBS, MEWS, and PER scores and hospital outcomes (p <0.004, p <0.001, p <0.001, respectively). A GBS score greater than 11 succesfully predicted bleeding at follow-up (p = 0.0237). GBS score's sensitivity for predicting endoscopic therapy was greater than those of other scoring systems. The discriminatory power of each scoring system was significant for predicting transfusion (p <0.0001, p = 0.0470, and p = 0.0014, respectively). A GBS score greater than 13, a MEWS score greater than 2, and a PER score greater than 3 predicted death. A PER score greater than 3 predicted rebleeding (p <0.0001).

Conclusion

The scoring systems in question can be easily calculated in patients presenting to ED with upper GIS bleeding and may be beneficial for risk stratification, determination of transfusion need, prediction of rebleeding, and decisions of hospitalization or discharge.

[Characterization of basal core promoter/precore gene mutations in chronically infected patients with hepatitis B virus genotype D in Mersin Province, Turkey]

The basal core promoter (BCP) and precore (PC) gene regions of hepatitis B virus (HBV) genome are important for the viral replication and synthesis of "e" antigen. Genetic variability has been described in PCP and PC gene regions, commonly in HBeAg negative patients. The aim of this study was to determine the frequency of the predominant mutation patterns of BCP/PC gene regions and their correlations with HBeAg status, HBV-DNA levels, and liver biochemical profiles in chronic hepatitis B (CHB) patients infected with genotype D, in Mersin province which is located at Mediteranean part of Turkey. A total of 54 CHB patients (33 male, 21 female; mean age: 40.05±12.91 years) infected with HBV genotype D were enrolled in the study. Serum HBV-DNA levels, serological markers (HBsAg, anti-HBs, HBeAg, anti-HBe, anti-HBc) and biochemical profiles (ALT and AST) were analyzed in all patients. BCP and PC gene regions were determined by polymerase chain reaction (PCR) and mutations of these regions were determined by direct sequencing of PCR products then aligned with known wild-type HBV sequences. BCP [nucleotide (nt.) 1753-1762/1764] and/or PC (nt. 1896) mutations were detected in 87.75% (43/49) of the patients. Mutation rates were detected as 97.1% (33/34) and 66.7% (10/15) in the HBeAg negative and in HBeAg positive patient groups, respectively (p=0.008). PC nt. G1896A mutation was more common in HBeAg negative samples than in HBeAg positive samples (73.5% vs. 20%, p=0.001), however there was no significant differences in the occurrence of BCP mutations between the two groups (p=0.331). No correlation was found between the presence of BCP and/or PC mutations and serum HBV-DNA or ALT-AST levels. Our study reveals that significant number of chronically infected patients with genotype D HBV have BCP and PC variants. G1896A stop codon mutation in precore region seems to have a significant role in the loss of HBeAg in our patients. The results of our study provided important data about the frequency and the genetic heterogeneity of different kinds of mutations occurring at BCP and PC gene regions.

Serum microRNAs; miR-30c-5p, miR-223-3p, miR-302c-3p and miR-17-5p could be used as novel non-invasive biomarkers for HCV-positive cirrhosis and hepatocellular carcinoma

Recently, serum miRNAs have been evolved as possible biomarkers for different diseases including hepatocellular carcinoma and other types of cancers. Investigating certain serum miRNAs as novel non-invasive markers for early detection of HCV-positive cirrhosis and hepatocellular carcinoma (HCC). The expression profiles of 58 miRNA were analyzed in patient's plasma of chronic hepatitis C (CHC), HCV-positive cirrhosis and HCV-positive HCC and compared with control group samples. Totally 94 plasma samples; 64 patient plasma (26 CHC, 30 HCV-positive cirrhosis, 8 HCV-positive HCC) and 28 control group plasma, were included. The expression profiles of 58 miRNAs were detected for all patient and control group plasma samples by qRT-PCR using BioMarkTM 96.96 Dynamic Array (Fluidigm Corporation) system. In CHC group, expression profiles of miR-30a-5p, miR-30c-5p, miR-206 and miR-302c-3p were found significantly deregulated (p < 0.05) when compared versus control group. In HCV-positive cirrhosis group, expression profiles of miR-30c-5p, miR-223-3p, miR-302c-3p, miR-17-5p, miR-130a-3p, miR-93-5p, miR-302c-5p and miR-223-3p were found significantly deregulated (p < 0.05). In HCV-positive HCC group, expression profiles of miR-17-5p, miR-223-3p and miR-24-3p were found significant (p < 0.05). When all groups were compared versus control, miR-30c-5p, miR-223-3p, miR-302c-3p and miR-17-5p were found significantly deregulated for cirrhosis and HCC. These results imply that miR-30c-5p, miR-223-3p, miR-302c-3p and miR-17-5p could be used as novel non-invasive biomarkers of HCV-positive HCC in very early, even at cirrhosis stage of liver disease.

Modified sequential Helicobacter pylori eradication therapy using high dose omeprazole and amoxicillin in the initial phase in the extensive metaboliser Turkish patients for CYP2C19 polymorphism is ineffective

AIM

To investigate whether the sequential therapy composed of high dose omeprazole and high dose amoxicillin in the first step was effective in eradication of H. pylori and whether there was a relation between effectiveness of the therapy and CYP2C19 gene polymorphism.

METHOD

134 dyspeptic patients with H. pylori were administered a modified sequential therapy composed of omeprazole 40 mg t.i.d. and amoxicillin 1000 mg t.i.d, for the first five days followed by omeprazole 20 mg b.d., metronidazole 500 mg t.i.d. and tetracycline 500 mg t.i.d, for the next five days. CYP2C19 genotype status was determined in patients. Hp eradication status was investigated by C14 UNT four weeks after treatment.

RESULTS

The eradication rates were 64.9% in ITT and 74.3% in PP analysis. In subgroup analyses, eradication rates were 73.8% and 60.8% (p: 0.145) in ITT for peptic ulcer and non-ulcer dyspepsia patients respectively and 86.1% and 69.1% (p: 0.052) in PP analysis for peptic ulcer and non-ulcer dyspepsia patients respectively. The difference was not significant. As for the CYP2C19 gene status, 81.5% of the patients had HoEM and 17.3% of the patients had HeEM, and eradication rates were 72% and 75% in ITT analysis for HoEM and HeEM respectively (p: 0.803) and 73.9% and 85.7% in PP analysis for HoEM and HeEM respectively (p: 0.347). There was not a significant difference in H. pylori eradication rates between the two groups.

CONCLUSION

This modified high-dose sequential therapy was ineffective in a Turkish sample, nearly all of whom had EM in terms of CYP2C19 gene status.

[Determination of hepatitis C virus genotype distribution in Mersin province, Turkey]

Hepatitis C virus (HCV) is a member of the Flaviviridae family and the RNA genome e x hibit high genetic heterogeneity. Six major genotypes were phylogenetically determined and each genotype contains different subtypes. The distribution of HCV genotypes varies geographically throughout the world. Determination of viral genotype has great importance in the selection of antiviral therapy, treatment duration and monitoring the response to treatment. The aim of this study was to determine the distribution of HCV genotypes in Mersin province located at the Southern part of Turkey. A total of 236 patients (137 females, 99 males; mean age: 53.28 ± 14.99 years) with chronic HCV infection who were admitted to Mersin University Hospital Microbiology Laboratory during March 2010-May 2012 period were included in the study. The patients were anti-HCV (ELISA; Abbott Laboratories, USA) and HCV-RNA (Cobas TaqMan 48, Roche Diagnostic, USA) positive. HCV genotype analysis was determined by using a commercial LiPA kit (Line Probe Assay; AMPLIQUALITY HCV-TS; AB Analitica, Italy) based on the reverse hybridization of amplification products of viral 5'-UTR region. Out of the 236 patients, genotype 1b was observed in 84.7% (n= 200), genotype 3a in 4.2% (n= 10), genotype 1 in 3.8% (n= 9), genotype 1a/1b in 2.1% (n= 5), genotype 4a in 2% (n= 2), genotype 1a in 1.7% (n= 4), genotype 2b in 1.3% (n= 3), genotype 2 in 0.4% (n= 1), genotype 2a/2c in 0.4% (n= 1) and genotype 6 in 0.4% (n= 1). In the cases infected with genotype 1b, statistically significant differences were detected between gender distribution with the mean serum ALT (46.14 IU/L in females, 63.9 IU/L in males; p= 0.029) and HCV-RNA (634 x 103 IU/L in females, 20 x 105 IU/L in males; p= 0.005) levels. This was the first study that reflected the distribution of HCV genotypes in southern Turkey region. Genotype 1b, associated with poor prognosis and which had the highest prevalence in Turkey, was also determined as the most common genotype with a rate of 84.7% in our region. In addition, low rates of genotype 1a, 2b, 3a and 4a which were identified with low frequency in our country and newly introduced genotype 6 were also demonstrated.

Detection of hepatitis B virus X gene and PreC promoter mutations from chronic hepatitis B patients in the south of Turkey

Hepatitis B virus (HBV) infection is a global health problem with more than 2 billion infected individuals. HBV infection leads to diverse outcomes ranging from acute to chronic hepatitis, which may result in severe complications as liver cirrhosis and hepatocellular carcinoma (HCC). HBV is one of the most important human DNA viruses having strong oncogenic potential. Recently, many studies have reported on HBV X gene and PreC promoter mutations associated with HCC. In order to detect the prevalence of HBx gene and PreC promoter mutations possibly related to HCC, we have analyzed sera samples collected from 61 patients with chronic hepatitis B. We have detected TI653 mutation in 1 of 61 (1,63%), A1896 mutation in 10 of 61 (16,39%), and T1762 - A1764 dual mutation in 4 of 61 (6,55%). T1653 and T1762- A1764 dual mutations were suggested significantly related to HCC in earlier reported studies. Our findings demonstrate that HBx gene and PreC promoter mutations related to HCC are present in our region and prospective clinical chord studies would be useful for better patient management and of early diagnosis of possible HCC cases.

Mutations of the gene encoding otogelin are a cause of autosomal-recessive nonsyndromic moderate hearing impairment

Already 40 genes have been identified for autosomal-recessive nonsyndromic hearing impairment (arNSHI); however, many more genes are still to be identified. In a Dutch family segregating arNSHI, homozygosity mapping revealed a 2.4 Mb homozygous region on chromosome 11 in p15.1-15.2, which partially overlapped with the previously described DFNB18 locus. However, no putative pathogenic variants were found in USH1C, the gene mutated in DFNB18 hearing impairment. The homozygous region contained 12 additional annotated genes including OTOG, the gene encoding otogelin, a component of the tectorial membrane. It is thought that otogelin contributes to the stability and strength of this membrane through interaction or stabilization of its constituent fibers. The murine orthologous gene was already known to cause hearing loss when defective. Analysis of OTOG in the Dutch family revealed a homozygous 1 bp deletion, c.5508delC, which leads to a shift in the reading frame and a premature stop codon, p.Ala1838ProfsX31. Further screening of 60 unrelated probands from Spanish arNSHI families detected compound heterozygous OTOG mutations in one family, c.6347C>T (p.Pro2116Leu) and c. 6559C>T (p.Arg2187X). The missense mutation p.Pro2116Leu affects a highly conserved residue in the fourth von Willebrand factor type D domain of otogelin. The subjects with OTOG mutations have a moderate hearing impairment, which can be associated with vestibular dysfunction. The flat to shallow "U" or slightly downsloping shaped audiograms closely resembled audiograms of individuals with recessive mutations in the gene encoding α-tectorin, another component of the tectorial membrane. This distinctive phenotype may represent a clue to orientate the molecular diagnosis.

[Determination of hepatitis B virus genotypes in chronic hepatitis B patients in Mersin province, Turkey]

Currently, ten genotypes (A-J) of hepatitis B virus (HBV) are identified based on the nucleic acid sequence heterogeneity, and these genotypes have been shown to have distinct geographic distribution. Reports of previous studies indicated that the genotype D is the predominant type among hepatitis B patients in different regions of Turkey, however there is no data for HBV genotypes to date from Mersin region. The aim of this study was to investigate the HBV genotypes by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) in chronic hepatitis B patients in Mersin province (located in the Mediterranean region of Turkey). A total of 54 serum samples were obtained from the chronic hepatitis B patients (33 male, 21 female; mean age: 40.05 years) followed-up at Gastroenterology Clinic of Mersin University Hospital. Patients had detectable HBV-DNA levels in their serum samples, and they were under antiviral therapy for at least one year. Genotyping of HBV was performed by RFLP analysis with the use of AvaII and MboI restriction enzymes after amplification of pre-S gene region by PCR. Confirmation of selected 18 cases was carried out with direct DNA sequencing. The genotypes were determined by phylogenetic comparison with 43 reference NCBI (National Center for Biotechnology Information) HBV sequences. Genotype determination was not successful in seven cases; since three of them were negative in preS-PCR, three of them yielded non-specific bands, and one of them exhibited a deleted PCR product, at the 300 bp level that was shorter than expected. Four different restriction patterns were determined in PCR-RFLP analysis of the remaining 47 samples. One of these patterns which was AvaII [-]/MboI [306/89/51], was clearly discriminated in 72.3% (34/47) of the samples as genotype D. Genotype discrimination of three patterns could not be done properly and these patterns were AvaII [- ]/MboI [357/306/89/51] (7/47, 14.9%), AvaII [300/146]/MboI [306/89/51] (5/47, 10.7%), and AvaII [- ]/MboI [357/89/---] (1/47, 2.1%). Phylogenetic comparison of HBV sequences demonstrated that all patterns in our cases were clustered in NCBI genotype D sequences. Patterns of AvaII [300/146]/MboI [306/89/51] and AvaII [-]/ MboI [357/89/---] and deleted sample were recognized as pre-S gene variants of HBV isolates. Our data indicated that the predominant HBV type was genotype D as commonly seen in Turkey and other Mediterranean countries. The results of this study also showed that the genotype uniformity and pre-S gene variants within the HBV isolates could be crucial in terms of understanding the molecular epidemiology of HBV circulating in the Mediterranean region of Turkey.

[Detection of Helicobacter pylori and antimicrobial resistance in gastric biopsy specimens]

Helicobacter pylori is reported as the etiological agent of gastritis, gastric and duodenal ulcer, gastric adenoid carcinoma and mucosa-associated lymphoid tissue lymphoma. In the diagnosis of H.pylori infections invasive (culture, histopathological examination, rapid urease test and molecular tests) and non-invasive (urea breath test, serological tests, stool culture and stool antigen/nucleic acid tests) methods may be used. Clarithromycin, amoxicillin and combination of metronidazole and protonpump inhibitor or ranitidine bismuth citrate triple treatment protocol is applied in order to treat and eradicate the infection. However, increasing rates of antibiotic resistance among H.pylori strains reduces the success of eradication therapy. The aim of this study was to investigate the presence of H.pylori in the gastric antral biopsy specimens and to determine the antimicrobial resistance of the isolates. A total of 149 gastric antral biopsy specimens obtained from patients (age range: 17-83 years; 73 were male) who admitted to Mersin University Faculty of Medicine Department of Internal Medicine Gastroenterology clinic with dyspeptic complaints were included in the study. H.pylori presence was investigated by culture, polymerase chain reaction (PCR) and urease test from gastric biopsy specimens, and H.pylori-specific antigen (HpSA) was investigated by ELISA in the stool samples of patients. Resistance to tetracycline, amoxicillin, metronidazole and levofloxacin was determined with E-test method. Clarithromycin resistance was determined both by E-test and PCR-RFLP (restriction fragment length polymorphism) methods. H.pylori was detected in 29.6% (43/145) of patients with culture, 55.2% (80/145) of patients with urease test, 57% (65/114) of patients with HpSA test and 71.3% (102/143) of patients with PCR. The sensitivity and specificity of culture, PCR, HpSA and urease tests were determined as 52.4% and 100%, 96.3% and 62.3%, 80.3% and 81.4%, 86.6% and 85.7%, respectively. According to the E-test results, resistance to clarithromycin was 18.2%, to tetracycline 9.1%, to metronidazole 45.5%, to levofloxacin 18.2% and no resistance was determined to amoxicillin. Clarithromycin resistance was searched in 94 of PCR positive 102 samples, and 17 (18.1%) of them yielded clarithromycin resistance. Of them 11 (64.7%) harbored A2144G (at 2144. nucleotide), and 6 (%35.3) harbored A2143G (at 2143. nucleotide) point mutations. In our study, PCR was determined as the most sensitive method, however due to its low specificity, the results should be confirmed with at least one of the other methods. The specificity of culture method was high, but sensitivity was found to be quite low compared with other methods. The sensitivity and specificity of urease and HpSA tests were found to be similar. In conclusion, in cases which endoscopy could not be done, non-invasive, rapid and practical HpSA method can be used in diagnosis and monitorization of the treatment. In the case of treatment failure, culture should be performed for antibiotic susceptibility testing of the isolate.