Occult hepatitis B virus infection: clinical implications in tuberculosis treatment

Occult hepatitis B virus infection (OBI) is characterized by the absence of HBsAg and persistence of the virus genome (HBV-DNA) in liver tissue and/or blood. OBI has been reported in several clinical contexts. However, the clinical significance of OBI in tuberculosis (TB) treatment is unknown. We investigated the OBI prevalence and its impact on the risk of drug-induced liver injury (DILI) during TB treatment. This was a prospective cohort study with one hundred patients who were treated for TB from 2008 to 2015. Laboratory, clinical and demographic data of TB patients were extracted from medical records. Based on HBV-DNA testing of serum samples, an OBI prevalence of 12% was established; almost half of these patients had both anti-HBc and anti-HBs serological markers. Low CD4⁺ cell counts have been shown to be a risk factor for OBI among TB patients co-infected with HIV (P=.036). High DILI incidence was observed in this study. A multivariable Cox proportional hazard model was conducted and identified OBI (HR 2.98, 95% CI 1.30-6.86) as the strongest predictor for DILI when adjusted to CD4⁺ cell count (HR 0.38, 95% CI 0.17-0.90), ALT before TB treatment (HR 1.37, 95% CI 0.81-2.32) and TB extrapulmonary clinical form (HR 2.91, 95% CI 1.75-7.21). The main aim of this study was to highlight DILI as a clinical outcome during treatment of TB patients with OBI. Therefore, HBV-DNA testing should be considered routinely in monitoring DILI, and also in other clinical implications associated with OBI, reduce morbidity and mortality.

Tuberculosis in Anti-Tumour Necrosis Factor-treated Inflammatory Bowel Disease Patients After the Implementation of Preventive Measures: Compliance With Recommendations and Safety of Retreatment

BACKGROUND AND AIMS

Despite having adopted preventive measures, tuberculosis (TB) may still occur in patients with inflammatory bowel disease (IBD) treated with anti-tumour necrosis factor (anti-TNF). Data on the causes and characteristics of TB cases in this scenario are lacking. Our aim was to describe the characteristics of TB in anti-TNF-treated IBD patients after the publication of the Spanish TB prevention guidelines in IBD patients and to evaluate the safety of restarting anti-TNF after a TB diagnosis.

METHODS

In this multicentre, retrospective, descriptive study, TB cases from Spanish hospitals were collected. Continuous variables were reported as mean and standard deviation or median and interquartile range. Categorical variables were described as absolute and relative frequencies and their confidence intervals when necessary.

RESULTS

We collected 50 TB cases in anti-TNF-treated IBD patients, 60% male, median age 37.3 years (interquartile range [IQR] 30.4-47). Median latency between anti-TNF initiation and first TB symptoms was 155.5 days (IQR 88-301); 34% of TB cases were disseminated and 26% extrapulmonary. In 30 patients (60%), TB cases developed despite compliance with recommended preventive measures; *not performing 2-step TST (tuberculin skin test) was the main failure in compliance with recommendations. In 17 patients (34%) anti-TNF was restarted after a median of 13 months (IQR 7.1-17.3) and there were no cases of TB reactivation.

CONCLUSIONS

Tuberculosis could still occur in anti-TNF-treated IBD patients despite compliance with recommended preventive measures. A significant number of cases developed when these recommendations were not followed. Restarting anti-TNF treatment in these patients seems to be safe.

Treatment Steps, Surgery, and Hospitalization Rates During the First Year of Follow-up in Patients with Inflammatory Bowel Diseases from the 2011 ECCO-Epicom Inception Cohort

BACKGROUND AND AIMS

The ECCO-EpiCom study investigates the differences in the incidence and therapeutic management of inflammatory bowel diseases [IBD] between Eastern and Western Europe. The aim of this study was to analyse the differences in the disease phenotype, medical therapy, surgery, and hospitalization rates in the ECCO-EpiCom 2011 inception cohort during the first year after diagnosis.

METHODS

Nine Western, five Eastern European centres and one Australian centre with 258 Crohn's disease [CD], 380 ulcerative colitis [UC] and 71 IBD unclassified [IBDU] patients [female/male: 326/383; mean age at diagnosis: 40.9 years, SD: 17.3 years] participated. Patients' data were registered and entered in the web-based ECCO-EpiCom database [www.epicom-ecco.eu].

RESULTS

In CD, 36 [19%] Western Europe/Australian and 6 [9%] Eastern European patients received biological therapy [p = 0.04], but the immunosuppressive [IS] use was equal and high in these regions [Eastern Europe vs Western Europe/Australia: 53% vs 45%; p = 0.27]. Surgery was performed in 17 [24%] CD patients in Eastern Europe and 13 [7%] in Western Europe/Australia [p < 0.001, pLogRank = 0.001]. Of CD patients from Eastern Europe, 24 [34%] were hospitalized, and 39 [21%] from Western Europe/Australia, [p = 0.02, pLogRank = 0.01]. In UC, exposure to biologicals and colectomy rates were low and hospitalization rates did not differ between these regions during the 1-year follow-up period [16% vs 16%; p = 0.93].

CONCLUSIONS

During the first year after diagnosis, surgery and hospitalization rates were significantly higher in CD patients in Eastern Europe compared with Western Europe/Australia, whereas significantly more CD patients were treated with biologicals in the Western Europe/Australian centres.

A genome-wide association study on copy-number variation identifies a 11q11 loss as a candidate susceptibility variant for colorectal cancer

Colorectal cancer (CRC) is a complex disease, and therefore its development is determined by the combination of both environmental factors and genetic variants. Although genome-wide association studies (GWAS) of SNP variation have conveniently identified 20 genetic variants so far, a significant proportion of the observed heritability is yet to be explained. Common copy-number variants (CNVs) are one of the most important genomic sources of variability, and hence a potential source to explain part of this missing genetic fraction. Therefore, we have performed a GWAS on CNVs to explore the relationship between common structural variation and CRC development. Phase 1 of the GWAS consisted of 881 cases and 667 controls from a Spanish cohort. Copy-number status was validated by quantitative PCR for each of those common CNVs potentially associated with CRC in phase I. Subsequently, SNPs were chosen as proxies for the validated CNVs for phase II replication (1,342 Spanish cases and 1,874 Spanish controls). Four common CNVs were found to be associated with CRC and were further replicated in Phase II. Finally, we found that SNP rs1944682, tagging a 11q11 CNV, was nominally associated with CRC susceptibility (p value = 0.039; OR = 1.122). This locus has been previously related to extreme obesity phenotypes, which could suggest a relationship between body weight and CRC susceptibility.

The roles of GSTM1 and GSTT1 null genotypes and other predictors in anti-tuberculosis drug-induced liver injury

WHAT IS KNOWN AND OBJECTIVE

Anti-tuberculosis drugs (ATD), although highly effective, often cause liver injury. Glutathione S-transferases (GST) play a crucial protective role in the detoxifying mechanisms of drugs. Several studies have investigated the genetic null variants of GSTM1 and GSTT1 as possible risk factors for ATD-induced liver injury; however, those findings are inconsistent. We investigated GSTM1 and GSTT1 null genotypes in Brazilian patients with tuberculosis (TB), adjusting for other possible predictors of ATD-induced liver injury.

METHODS

This was a prospective cohort study with patients who were treated for TB from 2006 to 2011. GSTM1 and GSTT1 gene deletions were analysed from genomic DNA by polymerase chain reaction (PCR). Demographic, clinical and laboratory data were extracted from medical records and possible predictors of liver injury were evaluated.

RESULTS AND DISCUSSION

This study enrolled 177 patients. Anti-tuberculosis drugs-induced liver injury incidence was 33.3%. Hepatitis B infection (HBV) and increased alanine aminotransferase (ALT) baseline were significant predictors. Neither GSTM1 nor GSTT1 null genotypes were associated with ATD-induced liver injury; nevertheless, the comparison among four different liver toxicity grades showed that GSTM1 non-null genotype was significant more frequent among the higher grades of liver toxicity.

WHAT IS NEW AND CONCLUSION

GSTM1 and GSTT1 null genotypes do not seem to play important roles in ATD-induced liver injury in Brazilians. However, there was evidence that GSTM1 polymorphisms were possibly related to the intensity of toxicity. Active HBV and initial high ALT could predict ATD-induced liver injury.

Can hepatitis B virus infection predict tuberculosis treatment liver toxicity? Development of a preliminary prediction rule

BACKGROUND

Liver toxicity due to tuberculosis (TB) treatment is a frequent cause of treatment interruption, and may sometimes lead to a change in therapy to a less potent regimen.

OBJECTIVE

To estimate the risk of hepatotoxicity in patients with or without hepatitis B virus (HBV) infection receiving TB treatment and to develop a clinical prediction rule.

DESIGN

A prospective observational follow-up was conducted. Data from 154 patients who underwent TB treatment were analysed. Crude risk ratios were estimated and a Cox proportional hazards model was fit.

RESULTS

The mean follow-up time was 187 days. Crude risk ratios showed that ethnicity, human immunodeficiency virus infection, multiple sexual partners, highly active antiretroviral treatment, and clinical forms of TB were possible predictors of liver toxicity. HBV infection and other sexually transmitted diseases showed considerable relative risk, although not statistically significant. The Cox proportional hazards model identified the following predictors of hepatotoxicity: White ethnicity, multiple sexual partners, high baseline alanine transferase and clinical forms of TB. Active HBV, indicated by the detection of surface antigen HBV, could predict hepatotoxicity, although with low precision.

CONCLUSION

Using this information, we were able to apply a score and draw a nomogram to estimate survival probabilities and median times to event for each patient.

Potential use of a Yersinia ruckeri O1 auxotrophic aroA mutant as a live attenuated vaccine

The aroA gene of Yersinia ruckeri, which encodes 5-enolpyruvylshikimate 3-phosphate synthase, was insertionally inactivated with a DNA fragment containing a kanamycin resistance determinant and reintroduced by allelic exchange into the chromosome of Y. ruckeri 21102 O1 by means of the suicide vector pIVET8. The Y. ruckeri aroA::Kan(r) mutant was highly attenuated when inoculated intraperitoneally into rainbow trout, with a 50% lethal dose of >5 x 10(7) CFU. The mutants were not recoverable from the internal organs 48 h post-inoculation or later. The vaccination of rainbow trout with the AroA mutant as a live vaccine conferred significant protection (relative percentage survival = 90%) against the pathogenic wild-type strain of Y. ruckeri.

Uncommon mutation pattern of a hepatitis B virus isolate from genotype F infecting a patient with AIDS

OBJECTIVE

To study the genomic variations of a hepatitis B virus (HBV) isolate in a patient coinfected with human immunodeficiency virus type 1 (HIV-1) who developed severe hepatitis and died of AIDS.

METHODS

Two blood samples were collected, the first one during the asymptomatic phase of HIV-1 infection, and the other, 3 years later, few months before the death of the patient. Both samples were HBsAg and anti-HBe positive. Pre-S/S and precore-core genome regions were PCR amplified and analyzed.

RESULTS

The HBV isolate belonged to genotype F, cluster IV. A number of unique amino acid substitutions were found in the surface antigen gene and the overlapping polymerase coding region of HBV genomes derived from both samples. However, these substitutions reflected natural variations rather than mutations of clinical significance. The precore stop codon mutation A(1896) was present in both genomes. Furthermore, the HBV genome derived from the second, but not first sample, showed two out-of-frame core interval deletions, one and 103 nucleotides in length, respectively.

CONCLUSIONS

This is the first report of an HBV isolate from genotype F with core internal deletions. Our results suggest an association between specific core mutations and the severe hepatitis developed by the patient.

Crystal structure of the class D beta-lactamase OXA-10

We report the crystal structure of a class D beta-lactamase, the broad spectrum enzyme OXA-10 from Pseudomonas aeruginosa at 2.0 A resolution. There are significant differences between the overall fold observed in this structure and those of the evolutionarily related class A and class C beta-lactamases. Furthermore, the structure suggests the unique, cation mediated formation of a homodimer. Kinetic and hydrodynamic data shows that the dimer is a relevant species in solution and is the more active form of the enzyme. Comparison of the molecular details of the active sites of the class A and class C enzymes with the OXA-10 structure reveals that there is no counterpart in OXA-10 to the residues proposed to act as general bases in either of these enzymes (Glu 166 and Tyr 150, respectively). Our structures of the native and chloride inhibited forms of OXA-10 suggest that the class D enzymes have evolved a distinct catalytic mechanism for beta-lactam hydrolysis. Clinical variants of OXA-10 are also discussed in light of the structure.

Integrated pervaporation/detection for the determination of fluoride in pharmaceuticals

A selective dynamic method for the determination of fluoride in pharmaceuticals based on the integration of pervaporation and potentiometric detection in a laboratory-made module is proposed. The analyte was continuously converted into volatile trimetylfluorosilane by reaction with hexamethyldisilazane, injected into a donor stream and accepted in a basic buffer solution after pervaporation. The method thus developed has a determination range between 1.5 and 200 mg l-1, precision (expressed as R.S.D.) of 3.4%, and has been applied to the determination of fluoride in different pharmaceutical products, with yields ranging between 90.6 and 100.3%. B.V.

Rotavirus serotype G5 associated with diarrhea in Brazilian children

Rotavirus serotype G5 in fecal specimens of 38 Brazilian children with diarrhea was identified by PCR and enzyme immunoassays. The strains exhibited long RNA electropherotypes and either subgroup II or nonsubgroup I-nonsubgroup II specificities. Serotype G5 has been found in piglets and horses but not yet in humans.

An outbreak of diarrhoea associated with rotavirus serotype 1 in a day care nursery in Rio de Janeiro, Brazil

Faeces from 17 children less than 1.6 years old and 15 adults more than 22 years old were collected during an outbreak of gastroenteritis in a day care nursery and screened for the presence of adenovirus and rotavirus by enzyme immunoassay (EIARA) and other viruses by electron microscopy (EM) and polyacrylamide gel electrophoresis (PAGE). Ten samples (58.8%) from children and one (6.7%) from adults were positive for rotavirus and all samples were negative for bacteria and parasites. No other viruses were observed in EM. An enzyme immunoassay test using monoclonal antibodies (MAb-EIA) to determine the subgroup(s) and the serotype(s) of rotavirus was performed and the results showed that all positive samples belong to serotype 1, subgroup II of group A rotaviruses. In PAGE test all samples had the same profile and the 10 and 11 dsRNA segments corresponded to the "long" profile of group A of rotaviruses. These results corroborated the MAb-EIA results and indicate a sole source of infection. The major symptoms observed were: vomiting (60%), fever (70%) and diarrhoea (100%). In previous years (1989 to 1991) we observed only rotavirus serotype 2 in this same day care nursery, but no outbreak was reported.

A simplified method for typing haemoglobin using ultrathin-layer isoelectric focusing

Haemoglobin alleles were identified by isoelectric focusing using ultrathin-layer polyacrylamide gels, containing pH 3.0-10.0 ampholytes. The run parameters were chosen to co-ordinate with other isoelectric focusing methods currently used by the authors' laboratory. The method devised separated the A, F, S, and C alleles.

Bilateral infraorbital block with 0.5% bupivacaine as post-operative analgesia following cheiloplasty in children

Various studies have shown that bupivacaine nerve blocks provide prolonged post-operative analgesia. We studied the efficacy of a 0.5% bupivacaine infraorbital nerve block as post-operative analgesia in a random, prospective, double blind manner in children undergoing cleft lip repair. Following the induction of anesthesia with ketamine 2-4 mg/kg im, 60 patients, aged 2-13 years, ASA I and II were equally divided: Group A received 1-1.5 ml bupivacaine, 0.5% with 1:200,000 epinephrine; Group B received 1-1.5 ml saline injected into the vicinity of the infraorbital foramina. In every patient, the surgeon infiltrated the lip with 4-7 ml of 1% lidocaine with 1:100,000 epinephrine for both anesthesia and hemostasis. Post-operative evaluations were completed after 4, 8, and 12 to 24 hours and were based on a visual analogue scale for pain. Similarly, the nurses and the parents also evaluated post-operative discomfort using specific criteria. All the observers were kept unaware of the solutions used for the block. The results showed that Group A was pain free for a mean duration of 19.4 +/- 5.06 (SD) hours in contrast to 11.7 +/- 6.19 hours for Group B, (p less than 0.001). Group A required no other analgesic whereas a total of 17 patients in Group B required analgesic medication starting at four hours post-operatively, (p less than 0.001). Both the nurses and the parents confirmed that those who received infraorbital block were more comfortable than those who did not. One-way analysis of variance indicates that the mean scores for both groups differs significantly at all levels of comparison, (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

A combined dot nitrocellulose-enzyme immunoassay for rotavirus and adenovirus

A combined enzyme immunoassay using nitrocellulose membrane as solid support is described for the detection of rotavirus and adenovirus in faeces from children with gastroenteritis. Its sensitivity and specificity are comparable to those of a previously described assay performed on plastic microplates (Pereira et al. (1985) J. Virol. Methods 10, 21-28). The introduction of nitrocellulose membrane as support for the immune reactions greatly simplifies the multiple washing steps and precludes the need for disposable plastic plates.

Determination of total cholesterol in serum by flow injection analysis with immobilized enzymes

Several photometric and fluorimetric methods are proposed for the determination of cholesterol by use of enzymes immobilized on controlled-pore glass and the normal and stopped-flow injection modes, achieving linear ranges of the calibration curves between 26-776 mumol/l and 5-265 mumol/l with excellent regression coefficients and good coefficients of variation. The methods have been applied to the determination of this analyte in serum with excellent results.

Diarrhoea in mice infected with a human rotavirus

Oral inoculation of newborn mice with the MET strain of human rotavirus produced transient diarrhoeal disease. Light and scanning electron microscopy showed typical rotavirus-induced morphological lesions in the villous epithelium of the small intestine consisting of extensive cytoplasmic vacuolation, villous necrosis and atrophy. Virus recovered from intestinal suspensions of infected mice showed the typical electrophoretic profile of the genome of the inoculated strain. Rotavirus antibody appeared in infected mice 10 to 20 days after inoculation but not in controls or nursing dams. The availability of a small animal model for experimental infection with human rotaviruses should prove useful for virulence and protection studies.