Prolonged use of tenofovir and entecavir in hepatitis B virus-related cirrhosis.

BACKGROUND AND AIMS: Limited data is available from India on outcome and efficacy of tenofovir and entecavir in hepatitis B virus (HBV)-related cirrhosis when used for prolonged time. We report the long-term efficacy and outcome of these antiviral drugs in patients with chronic HBV infection, with compensated or decompensated cirrhosis. METHODS: We retrospectively analyzed laboratory and clinical data of 400 HBV-related cirrhotic patients without access to liver transplantation, who were treated with tenofovir/entecavir therapy, from January 2007 to January 2014. Two hundred and ten (52.5 %) patients had at least one of the components of decompensation at baseline. Two hundred and twenty (55 %) and 180 (45 %) patients were initiated tenofovir and entecavir, respectively. Follow up period was 45 (12-68) months for tenofovir and 36 (11-60) months for entecavir. RESULTS: At the end of 1 year, levels of HBV DNA <20 IU/mL were achieved in 91.8 % and 88.8 % of patients, and alanine aminotransferase normalized in 54.5 % and 55.5 % of patients who received tenofovir and entecavir, respectively. At the last visit, Child-Turcotte-Pugh scores improved among 29.5 % of patients who received tenofovir, 25 % of those who received entecavir, and remained stable in 61.9 % and 65 % patients, respectively, in both groups. The 5-year cumulative rate of liver decompensation, hepatocellular carcinoma, and cirrhosis-related complications were 3.1 %, 1.9 %, and 2.1 % with an annual incidence of 0.8 %, 0.3 %, and 0.5 % per person-year, respectively. CONCLUSION: Tenofovir and entecavir were effective and potent drugs for prolonged treatment of HBV cirrhosis and improved the overall clinical course.

Diagnosis of Helicobacter pylori: what should be the gold standard?

Since the discovery of Helicobacter pylori (H. pylori) in 1983, numerous detection methods for the presence of the bacterium have been developed. Each one of them has been associated with advantages and disadvantages. Noninvasive tests such as serology, (13)C urea breath test (UBT) and stool antigen tests are usually preferred by the clinicians. Serology has its own limitation especially in endemic areas while (13)C UBT is technically very demanding. The stool antigen detection method, although specific, is usually associated with poor sensitivity. The (13)C UBT is believed to be specific, but with present revelation of the fact that stomach is colonized by many other urease producing bacteria makes it questionable. Histology, culture, rapid urease test and polymerase chain reaction (PCR) are the tests which are carried out on antral biopsies collected by invasive means. Histology has been proposed to be very sensitive and specific but the question is how by simply looking the morphology of the bacteria in the microscope, one can claim that the curved bacterium is exclusively H. pylori. Rapid urease test (RUT), the doctor's test, is also challenged because the presence of other urease producing bacteria in the stomach cannot be denied. Moreover, RUT has been reported with poor sensitivity specially, when density of the bacterium is low. Isolation of H. pylori is essential to investigate its growth requirements, antibiotic susceptibility testing, studying virulence factor to develop vaccine and many more explorations. It has also got several disadvantages i.e., special condition for transporting, media, incubation and few days waiting for the colonies to appear, apart from the speed essentially needed to process the specimens. Till date, majority of the microbiological laboratories in the world are not equipped and trained to isolate such fastidious bacterium. The option left is PCR methods to detect H. pylori's DNA in gastric mucosa, gastric juice, saliva, dental plaques and environmental specimens. There are speculations for false positivity due to detection of non-pylori Helicobacters due to genetic sharing; and false negativity due to low bacterial counts and presence of PCR inhibitors. However, specimen collection, transportation and processing do not require speed and special conditions. PCR based diagnosis may be considered as gold standard by designing primers extremely specific to H. pylori and targeting at least more than one conserved genes. Similarly specificity of PCR may be improved by use of internal Primers. Further, nested PCR will take care of false negatives by countering the effect of PCR inhibitors and low bacterial counts. Therefore, nested PCR based methods if performed properly, may be proposed as gold standard test.

Helicobacter pylori is not eradicated after triple therapy: a nested PCR based study.

Detection of Helicobacter pylori after triple therapy is usually carried out by either rapid urease test (RUT), urea breath test (UBT), histology, bacterial isolation, and single round PCR or serological tests. In this study, antral biopsy specimens from 25 patients were tested for H. pylori by RUT, culture, histology, and nested PCR in their antral biopsy specimens before and after treatment. Three genes, namely, heat shock protein (hsp60), phosphoglucosamine mutase (ureC), and flagellar export ATP synthase (fliI) of H. pylori were targeted. Of the 25 antral biopsy specimens, the RUT, culture, histology, and nested PCR positivity dropped from 81.8% to 12%, 31% to 0%, 100 to 84%, and 100% to 92%, respectively, before and after therapy. Further, hsp60 specific amplicons from 23 out of 25 patients gave identical restriction pattern, while 6 fliI and 1 ureC specific amplicon produced different restriction pattern. Furthermore, variations in fliI gene sequences in H. pylori after treatment were also confirmed by sequencing and compared in silico. Nested PCR based detection of H. pylori is more sensitive method to detect H. pylori after therapy than culture, RUT, and histology. Further, this study suggests that H. pylori is not eradicated completely after triple therapy.

Pseudomonas fluorescens-like bacteria from the stomach: a microbiological and molecular study.

AIM: To characterize oxidase- and urease-producing bacterial isolates, grown aerobically, that originated from antral biopsies of patients suffering from acid peptic diseases. METHODS: A total of 258 antral biopsy specimens were subjected to isolation of bacteria followed by tests for oxidase and urease production, acid tolerance and aerobic growth. The selected isolates were further characterized by molecular techniques viz. amplifications for 16S rRNA using universal eubacterial and HSP60 gene specific primers. The amplicons were subjected to restriction analysis and partial sequencing. A phylogenetic tree was generated using unweighted pair group method with arithmetic mean (UPGMA) from evolutionary distance computed with bootstrap test of phylogeny. Assessment of acidity tolerance of bacteria isolated from antrum was performed using hydrochloric acid from 10(-7) mol/L to 10(-1) mol/L. RESULTS: Of the 258 antral biopsy specimens collected from patients, 179 (69.4%) were positive for urease production by rapid urease test and 31% (80/258) yielded typical Helicobacter pylori (H. pylori) after 5-7 d of incubation under a microaerophilic environment. A total of 240 (93%) antral biopsies yielded homogeneous semi-translucent and small colonies after overnight incubation. The partial 16S rRNA sequences revealed that the isolates had 99% similarity with Pseudomonas species. A phylogenetic tree on the basis of 16S rRNA sequences denoted that JQ927226 and JQ927227 were likely to be related to Pseudomonas fluorescens (P. fluorescens). On the basis of HSP60 sequences applied to the UPGMA phylogenetic tree, it was observed that isolated strains in an aerobic environment were likely to be P. fluorescens, and HSP60 sequences had more discriminatory potential rather than 16S rRNA sequences. Interestingly, this bacterium was acid tolerant for hours at low pH. Further, a total of 250 (96.9%) genomic DNA samples of 258 biopsy specimens and DNA from 240 bacterial isolates were positive for the 613 bp amplicons by targeting P. fluorescens-specific conserved putative outer membrane protein gene sequences. CONCLUSION: This study indicates that bacterial isolates from antral biopsies grown aerobically were P. fluorescens, and thus acid-tolerant bacteria other than H. pylori can also colonize the stomach and may be implicated in pathogenesis/protection.

Mucosal IgA & IL-1ß in Helicobacter pylori Infection.

Helicobacter pylori infection stimulates strong local inflammatory and specific IgA antibody production. The influence of antibodies on the bacterial colonization is not clear. Here, we have analysed the association between the mucosal IgA level and IL-1ß in various manifestations of the infection seen endoscopically. Antral biopsies of 57 dyspeptic patients were taken for culture, histology and estimation of mucosal levels of anti-H. pylori IgA and IL-1ß. Mean mucosal IgA level was higher in patients with normal mucosa compared to all other groups and lower IgA level was associated with higher bacterial density. IL-1ß was higher in ulcer patients and suspicious malignancy group as compared to normal group and higher level of IL-1ß was associated with higher grades of metaplasia. Present study indicates that local immunity seems to have a protective role against H. pylori infection and higher level of IL-1ß induced by the pathogen may be associated with metaplasia and carcinogenesis.

Chronic pancreatitis. A prospective nationwide study of 1,086 subjects from India.

CONTEXT: Chronic pancreatitis is common in India. However, its risk factors are not clear. There is sparse data on the current prevalence of tropical pancreatitis in India. OBJECTIVE: To undertake a prospective nationwide study of the risk factors and clinical profile of chronic pancreatitis. SETTING: Thirty-two major centers from different regions of India contributed data on 1,086 patients to a common online website (www.ipans.org). MAIN OUTCOME MEASURES: Risk factors, clinical features complications and treatment of chronic pancreatitis. RESULTS: Of the 1,086 subjects, complete data on risk factors were available for 1,033 subjects. Idiopathic pancreatitis was the most common form of pancreatitis (n=622; 60.2%) and alcoholic chronic pancreatitis accounted for about a third of the cases (n=400; 38.7%); the rest (n=11; 1.1%) had rare risk factors. Smoking and cassava intake were documented in 292 (28.3%) and 189 (18.3%) subjects, respectively. Using well-defined criteria, only 39 (3.8%)cases could be labeled as 'tropical pancreatitis'. Pain occurred in 971 patients (94.0%). Four hundred and eighteen (40.5%) subjects had diabetes mellitus. Of alcohol consumers, alcoholism and female gender were independent risk factors for diabetes in subjects with chronic pancreatitis (OR=1.48, P=0.003; and OR=1.75, P<0.001, respectively). The most common complications were pseudocysts (15.8%) and biliary obstruction (8.2%). Pancreatic cancer occurred in 42 subjects (4.1%). Ultrasound detected calculi in 69.7%, ductal dilatation in 63.4% and atrophy in 27.3%. The majority of patients were on medical therapy (n=849; 82.2%); endotherapy and surgery accounted for the rest. About 50% percent of the patients with diabetes required insulin (198/418). CONCLUSIONS: In this first nationwide prospective survey of chronic pancreatitis in India, idiopathic pancreatitis was the most common form, followed by alcoholic pancreatitis. The classical form of tropical chronic pancreatitis is becoming less common.

Evaluation of nested PCR in detection of Helicobacter pylori targeting a highly conserved gene: HSP60.

OBJECTIVE: To comparatively evaluate a new nested set of primers designed for the detection of Helicobacter pylori targeting a highly conserved heat shock protein gene (Hsp60). METHODS: A total of 60 subjects having peptic ulcer diseases were tested for the detection of H. pylori using rapid urease test (RUT), histology, culture, and polymerase chain reaction (PCR) in their antral biopsy specimens. A newly designed Hsp60 gene-based primer set was evaluated against commonly used PCR primers for detection of H. pylori. RESULTS: Forty-six of the 60 study subjects were found positive for culture isolation and all the 46 culture-positive specimens were also positive with Hsp60 gene PCR. Of the 46 culture-positive specimens, 44 were positive for 16S rRNA gene, ureC gene, RUT, and histology whereas only 29 were positive with ureA gene PCR. Of the 14 culture-negative subjects, 10 were positive with 16S rRNA gene, 4 were positive with ureC (glmM) gene PCR, and 2 were positive with RUT and 1 was positive on histology. CONCLUSION: This study shows that nested amplification targeting Hsp60 gene is the most sensitive and specific with LR+ and LR- values of proportional, variant and 0, respectively, when compared with the other three PCR methods. Also, HSP60 gene-specific nested protocol was the most appropriate for detection of H. pylori in clinical specimens. This is particularly valuable because it can be used as a noninvasive method for detecting H. pylori infection in young children and also, in follow-up studies with peptic ulcer patients, on samples like feces and saliva.

Detection of Helicobacter pylori in stool specimens: comparative evaluation of nested PCR and antigen detection.

BACKGROUND: Efficacy of Helicobacter pylori stool antigen enzyme immunoassay (HpSA) and stool PCR was evaluated, before and after treatment, in a country with a high prevalence of H. pylori infection. METHODOLOGY: A total of 52 patients with dyspeptic symptoms were included in the study. Antral biopsy was collected during pre- and post-therapy periods for rapid urease test (RUT) and PCR. Similarly stool specimens for PCR and HpSA test were collected during both the periods from all 52 patients. Biopsy, PCR and RUT results together were considered the "gold standard." RESULTS: On the basis of gold standard tests, 40/52 patients were H. pylori positive. The sensitivity and specificity of HpSA test were 80% and 83.3% respectively in untreated patients. On the other hand, the sensitivity and specificity of stool PCR in untreated patients were 72.5% and 100% respectively. After eradication therapy, the results of both RUT and biopsy PCR were negative in 87.5% and positive in 12.5% of the patients. Although post treatment sensitivity of HpSA and stool PCR was equal (60%), specificity of HpSA and stool PCR were 68.6% and 97.1% respectively. CONCLUSION: The H. pylori stool tests represent a non-invasive concept for diagnosis of infection. Both HpSA and stool PCR seem to be satisfactory tests for pre-eradication as well as assessment of infection. But stool PCR is a better indicator than HpSA test in the post-eradication assessment of infection.

Association of carcinoma of the gallbladder with typhoid carriage in a typhoid endemic area using nested PCR.

BACKGROUND: Although well studied the association between chronic typhoid carrier state and carcinoma of the gallbladder (CaGB) remains unproven. METHODOLOGY: The study was performed at a tertiary care medical center in North India and involved 52 patients with CaGB, 223 patients with benign gallbladder diseases, 508 healthy individuals and, 424 corpses. For the detection of Salmonella enterica serovar Typhi, hepatobiliary specimens were subjected to DNA extraction for specific nested- PCR amplification of the S. Typhi flagellin gene. Anti-Vi S. Typhi antibodies were detected in serum samples from patients by indirect haemagglutination. RESULTS: Thirty five of the 52 (67.3%) CaGB patients were PCR-positive for the S. Typhi flagellin gene; significantly higher than for patients with benign gallbladder diseases (95/223, 42.6%; p<0.01) and corpses (35/424, 8.2%; p<0.001). The numbers of individuals that had significant anti-Vi antibody titres (> or = 160) in their serum were 20/52 (38.5%) for CaGB patients, 31/223 (13.9%) for patients with benign gallbladder diseases, and 47/508 (9.2%) for healthy individuals. CONCLUSIONS: Specific nested-PCR amplification of the S. Typhi flagellin gene in hepato-biliary specimens was more sensitive for detection of S. Typhi carriage than anti-Vi antibody titres in serum. The results demonstrate an association between typhoid carriage and gallbladder diseases, both CaGB and benign. S. Typhi specific immunosuppression is also suggested in patients with gallbladder diseases.

Asymptomatic chronic hepatitis B virus infection in northern India.

BACKGROUND: Chronic infection with hepatitis B virus (HBV) causes a spectrum of diseases ranging from asymptomatic infective state to cirrhosis and hepato-cellular carcinoma. The asymptomatic state has highly variable characteristics. METHODS: Sixty-one incidentally detected asymptomatic HBsAg-positive subjects (IDAHS), in whom HBsAg positivity persisted for > 6 months, were studied for liver biochemistry, HBeAg, anti HBe and HBV DNA levels (in HBeAg-negative subjects). Liver biopsy was done in 29 subjects and scored for histological activity index (HAI) and fibrosis using modified Knodell score. RESULTS: Thirteen (21%) subjects were HBeAg positive. The remaining 48 (79%) were positive for anti HBe, with HBV DNA level of> 105 copies/mL in 15 (31.2%). Transaminase elevation was more frequent in HBeAg-positive subjects (69%; p< 0.05) and in HBV DNA-positive (93%) than in non-replicative (27%) infection. Seroconverted (anti HBe-positive) individuals were a decade older than HBeAg-positive ones and most (93.7%) of them were> 20 years of age. Fifteen of 29 (51.3%) had HAI> 3, more frequently in those with raised ALT (68.4%; p< 0.05) than with normal ALT (20%), but there was no difference in relation to HBeAg status. CONCLUSIONS: Seroconversion to anti HBe was noted in individuals aged 20 years or more. Ongoing liver disease was noted in approximately half of IDAHS, suggesting that a considerable proportion of IDAHS have active infection. In HBeAg-negative subjects, transaminase estimation may be sufficient in planning therapy.

The interaction between antiretroviral agents and tacrolimus in liver and kidney transplant patients.

Solid organ transplantations have been performed successfully in selected HIV-positive patients with highly active antiretrovirus therapy (HAART). However, some of the medications in the HAART regimen require metabolism via the cytochrome P4503A, the same enzyme complex responsible for clearance of the calcineurin inhibitors cyclosporine and tacrolimus. Several case reports have described significant interactions between the agents used in HAART and immunosuppressive drugs. The goal of this report is to examine the extent of potential drug interactions between antiretroviral agents and tacrolimus after liver and kidney transplantation. Seven liver transplant (LTx) patients (M = 6, F = 1) and four kidney transplant (KTx) patients (M = 4) infected with HIV underwent surgery between September 1997 and January 2001. Initial immunosuppression consisted of tacrolimus and steroids for LTx patients or tacrolimus, steroids, and mycophenolate mofetil for KTx recipients. Their current baseline immunosuppression and HAART regimen were examined retrospectively. Of the seven liver recipients, one (case 4) died 2 weeks after LTx and never received HAART therapy posttransplantation. The remaining six patients were placed on a regimen consisting of two nucleoside reverse transcriptase inhibitors (NRTI) and one protease inhibitor (PI) (nelfinavir in 5, indinavir in 1) based on known viral sensitivities or history of a previous clinical response. Kidney recipients received NRTI and nonnucleoside reverse transcriptase inhibitors (NNRTI). The mean dose of tacrolimus in liver recipients was 0.6 mg/d, with mean trough concentration of 9.7 mg/mL. Compared with historic controls (liver transplant patients not on HAART), the average tacrolimus dose was 16-fold lower in patients on HAART. In contrast to liver recipients, HIV-positive kidney recipients not on PI therapy required a mean tacrolimus dose of 9.5 mg/d to maintain a mean trough concentration of 9.6 ng/mL. Of the two protease inhibitors used, nelfinavir seems to have a more profound effect than indinavir. When patients on nelfinavir alone (n = 5) were compared with a control group not on antiretroviral therapy, the need for a tacrolimus dose was 38 times lower (mean dose, 0.26 mg/d). Profound drug interactions between PI and tacrolimus have been observed requiring up to 50-fold reductions in dosage. This effect seems to be most pronounced with the use of nelfinavir as opposed to indinavir, although further experience is required to confirm this observation. In contrast, HAART using NRTI and NNRTI without the use of PI, as shown in kidney recipients, produces less significant effects on tacrolimus metabolism. Great caution and frequent drug level monitoring are necessary when HAART is introduced or withdrawn in HIV-positive recipients of organ transplants.