High prevalence of hepatitis B virus infection among tuberculosis patients with and without HIV in Rio de Janeiro, Brazil

Antiviral Therapy for Hepatitis B Prevents Liver Injury in Patients With Tuberculosis and Hepatitis B Coinfection

BACKGROUND

Chronic hepatitis B virus (HBV) infection increases the risk of liver injury in patients who undergo antituberculosis treatment. It is uncertain whether antiviral treatment for HBV at the time of tuberculosis diagnosis would reduce the risk of liver injury.

METHODS

We performed a population-level, retrospective, cohort study that involved all patients with tuberculosis-HBV coinfection treated in public hospitals in Hong Kong over a 16-year period. Patients who received antiviral treatment at the time of tuberculosis diagnosis were considered "patients on antiviral therapy." A multivariable Cox proportional hazards model was used to determine the adjusted hazard ratio of hospitalization due to drug-induced liver injury within 1 year in patients on antiviral therapy, adjusting for the propensity score.

RESULTS

Of 3698 patients with tuberculosis-HBV coinfection, 488 (13.2%) were patients on antiviral therapy. Of the remaining 3210 patients, 446 (13.9%) started antiviral therapy within 1 year of tuberculosis diagnosis. Adjusting for the propensity score, patients on antiviral therapy had a lower risk of hospitalization due to drug-induced liver injury compared with those not on treatment (adjusted hazard ratio, 0.44; 95% confidence interval .26-.72). Compared with patients who started antiviral therapy within 1 year of tuberculosis diagnosis, patients on antiviral therapy also had a lower risk of hospitalization due to drug-induced liver injury and a lower risk of liver-related mortality.

CONCLUSIONS

We show that antiviral treatment for HBV given at the time of tuberculosis diagnosis reduced the risk of liver injury in tuberculosis-HBV coinfected patients.

Examining the Complex Relationship Between Tuberculosis and Other Infectious Diseases in Children

Millions of children are exposed to tuberculosis (TB) each year, many of which become infected with Mycobacterium tuberculosis. Most children can immunologically contain or eradicate the organism without pathology developing. However, in a minority, the organism overcomes the immunological constraints, proliferates and causes TB disease. Each year a million children develop TB disease, with a quarter dying. While it is known that young children and those with immunodeficiencies are at increased risk of progression from TB infection to TB disease, our understanding of risk factors for this transition is limited. The most immunologically disruptive process that can happen during childhood is infection with another pathogen and yet the impact of co-infections on TB risk is poorly investigated. Many diseases have overlapping geographical distributions to TB and affect similar patient populations. It is therefore likely that infection with viruses, bacteria, fungi and protozoa may impact on the risk of developing TB disease following exposure and infection, although disentangling correlation and causation is challenging. As vaccinations also disrupt immunological pathways, these may also impact on TB risk. In this article we describe the pediatric immune response to M. tuberculosis and then review the existing evidence of the impact of co-infection with other pathogens, as well as vaccination, on the host response to M. tuberculosis. We focus on the impact of other organisms on the risk of TB disease in children, in particularly evaluating if co-infections drive host immune responses in an age-dependent way. We finally propose priorities for future research in this field. An improved understanding of the impact of co-infections on TB could assist in TB control strategies, vaccine development (for TB vaccines or vaccines for other organisms), TB treatment approaches and TB diagnostics.

Prevalence of hepatitis B, hepatitis C and human immunodeficiency viral infections in patients with inflammatory bowel disease in north India

Background/Aims

Patients with inflammatory bowel disease (IBD) often require immunosuppressive therapy and blood transfusions and therefore are at a high risk of contracting infections due to hepatitis B (HBV) and hepatitis C (HCV) and human immunodeficiency virus (HIV). In the present study, we assessed the prevalence of these infections in patients with IBD.

Methods

This retrospective study included 908 consecutive patients with IBD (ulcerative colitis [UC], n=581; Crohn's disease [CD], n=327) who were receiving care at a tertiary care center. Ninety-five patients with intestinal tuberculosis (ITB) were recruited as disease controls. Prospectively maintained patient databases were reviewed for the prevalence of HBV surface antigen, anti-HCV antibodies, and HIV (enzyme-linked immunosorbent assay method). HCV RNA was examined in patients who tested positive for anti-HCV antibodies. Prevalence data of the study were compared with that of the general Indian population (HBV, 3.7%; HCV, 1%; HIV, 0.3%).

Results

The prevalence of HBV, HCV, and HIV was 2.4%, 1.4%, and 0.1%, respectively, in the 908 patients with IBD. Among the 581 patients with UC, 2.2% (12/541) had HBV, 1.7% (9/517) had HCV, and 0.2% (1/499) had HIV. Among the 327 patients with CD, 2.8% (8/288) had HBV, 0.7% (2/273) had HCV, and 0% (0/277) had HIV. One patient with CD had HBV and HCV coinfection. The prevalence of HBV, HCV, and HIV in patients with ITB was 5.9% (4/67), 1.8% (1/57), and 1.2% (1/84), respectively.

Conclusions

The prevalence of HBV, HCV, and HIV in north Indian patients with IBD is similar to the prevalence of these viruses in the general community. Nonetheless, the high risk of flare after immunosuppressive therapy mandates routine screening of patients with IBD for viral markers.

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.

Human immunodeficiency virus and hepatitis B virus co-infections among tuberculosis patients attending a Model Rural Health Research Unit in Ghatampur, North India

INTRODUCTION

This prospective cross-sectional hospital-based study was carried out in order to assess the prevalence of human immunodeficiency virus (HIV) and hepatitis B virus (HBV) infections among patients with active tuberculosis (TB) disease attending an Outpatient Department (OPD) at the Model Rural Health Research Unit in Ghatampur, a rural village in Kanpur district.

MATERIALS AND METHODS

The socio-demographic features and clinical profile of the TB patients were analysed in the context of symptoms at the time of testing. The HIV and HBV status were determined and correlated with clinical features at the time of testing.

RESULTS

In our study, the prevalence of HIV infection among TB patients is 1.48% (18/1215) and that of HBsAg reactivity was found to be 2.96% (36/1215). During 2007-2010, the HIV-positivity varied between 1.5% and 1.45% whereas HBV reactivity ranged between 2.4% and 3.63%.A substantial percentage of the TB patients attending the OPD in Ghatampur harbour HIV and HBV infections, which otherwise would remain undiagnosed without serological screening.

CONCLUSION

Co infection with HBV among TB patients potentiate the risk of anti-tuberculous therapy-induced hepatotoxicity, therefore, exercising caution and carefully monitoring the patients for drugs associated hepatotoxicity is essential. There is an urgent need to perform population-based surveys of HIV and hepatitis infections among TB patients to assess the true extent of the problem. Efforts should be made to make physicians aware of the peculiarities and manage these patients effectively.

Low prevalence of hepatitis B and C among tuberculosis patients in Duhok Province, Kurdistan: Are HBsAg and anti-HCV prerequisite screening parameters in tuberculosis control program?

OBJECTIVE/BACKGROUND

Viral hepatitis, particularly hepatitis B virus (HBV) and hepatitis C virus (HCV), infections and tuberculosis (TB) are a global public health concern. Co-infection with HBV or HCV among TB patients may potentiate the risk of hepatotoxicity induced by anti-TB drugs. Hence, the aim of this study was to identify the prevalence of HBV and HCV among TB patients included in the Duhok National Tuberculosis Program (NTP).

METHODS

The Duhok NTP Center is a specialized institution in Duhok City, Iraq, concerned with management and follow-up of TB patients. A cross-sectional study was conducted at the center between June 2015 and May 2016. All documented TB patients were analyzed on the basis of socio-demographic and other characteristics. Thereafter, all patients underwent screening for hepatitis B surface antigen (HBsAg), anti-HCV, and anti-HIV using enzyme-linked immunosorbent assay (ELISA). The results obtained were analyzed by entering the data in binary format into a Microsoft Excel spreadsheet. A p value of <.05 was considered to be statistically significant.

RESULTS

Two-hundred fourteen documented TB patients were recruited in this study, with 127 (59.3%) males and 87 (40.7%) females. The mean age of the patients was 40.34years (±20.29). Of the total number of patients, four cases (1.8%) were HBsAg-positive and one case (0.9%) was positive for anti-HCV. The variables significantly associated with HBV were history of surgical dental procedure [odds ratio (OR), 0.04; 95% confidence interval (CI), -0.01 to 0.04; p=.03], and nationality (OR, 13.67; 95% CI, 0.46-210.85; p=.007).

CONCLUSION

The prevalence of HBV and HCV co-infection among TB patients in this study was low. This may be explained by the low rate of blood transfusion among the patients, the very low prevalence of HIV infections in Kurdistan, the negative history of injection drug use, and adherence to universal infection-control measures, including vaccination for HBV. Both history of dental intervention and belonging to a Syrian population were independent risk factors for HBV/TB co-infection.

Serological markers of hepatitis B and C in patients with HIV/AIDS and active tuberculosis

Infection with hepatitis B virus (HBV) and C virus (HCV) are common in patients with HIV/AIDS and tuberculosis (TB). This is a cross-sectional study with patients infected with HIV/AIDS and active TB in Recife, Brazil, aiming to verify the prevalence of markers for HBV: antibody to hepatitis B core antigen (anti-HBc); and HCV: antibody to hepatitis C virus (anti-HCV) by chemiluminescence, and to identify the frequency of associated factors. Data were collected through questionnaires, and blood was drawn from patients for analysis. We used the chi-square test and the Fisher exact test when necessary. We conducted a bivariate logistic regression analysis and the magnitude of the associations was expressed as odds ratio (OR) with a confidence interval of 95%. Among 166 patients studied with HIV/AIDS and active TB, anti-HBc was positive in 61 patients [36.7%; 95%CI (29.4-44.6%)] and anti-HCV in 11[6.6%; 95%CI (3.4-11.5%)]. In the logistic regression analysis, male sex, and age ≥40 years were independent factors associated with the occurrence of anti-HBc. In conclusion, we verified a high frequency of HBV contact marker and a low frequency of HCV markers in patients with HIV/AIDS and TB in Recife.

Viral hepatitis prevalence in patients with active and latent tuberculosis

AIM: To assess the prevalence of hepatitis B virus (HBV) and hepatitis C virus (HCV) infection and association with drug induced liver injury (DILI) in patients undergoing anti-tuberculosis (TB) therapy.

METHODS: Four hundred and twenty nine patients with newly diagnosed TB - either active disease or latent infection - who were due to commence anti-TB therapy between September 2008 and May 2011 were included. These patients were prospectively tested for serological markers of HBV, HCV and human immunodeficiency virus (HIV) infections - hepatitis B core antigen (HBcAg), hepatitis B surface antigen (HBsAg), hepatitis B e antigen, IgG and IgM antibody to HBcAg (anti-HBc), HCV IgG antibody and HIV antibody using a combination of enzyme-linked immunosorbent assay, Western blot assay and polymerase chain reaction techniques. Patients were reviewed at least monthly during the TB treatment initiation phase. Liver function tests were measured prior to commencement of anti-TB therapy and 2-4 wk later. Liver function tests were also performed at any time the patient had significant nausea, vomiting, rash, or felt non-specifically unwell. Fisher’s exact test was used to measure significance in comparisons of proportions between groups. A P value of less than 0.05 was considered statistically significant.

RESULTS: Of the 429 patients, 270 (62.9%) had active TB disease and 159 (37.1%) had latent TB infection. 61 (14.2%) patients had isolated anti-HBc positivity, 11 (2.6%) were also HBsAg positive and 7 (1.6%) were HCV-antibody positive. 16/270 patients with active TB disease compared to 2/159 patients with latent TB infection had markers of chronic viral hepatitis (HBsAg or HCV antibody positive; P = 0.023). Similarly the proportion of HBsAg positive patients were significantly greater in the active vs latent TB infection group (10/43 vs 1/29, P = 0.04). The prevalence of chronic HBV or HCV was significantly higher than the estimated United Kingdom prevalence of 0.3% for each. We found no association between DILI and presence of serological markers of HBV or HCV. Three (5.3%) patients with serological markers of HBV or HCV infection had DILI compared to 25 (9.5%) patients without; P = 0.04.

CONCLUSION: Viral hepatitis screening should be considered in TB patients. DILI risk was not increased in patients with HBV/HCV.

[A 45 year-old male with lumbar tumours]

A 45 year old Filipino male, with history of Hepatitis B virus infection, was seen in his primary care clinic with a lumbar mass for the past three months. On physical examination the lower limbs showed decrease strength, chest X-rays showed bilateral thickening of the apical pleura, the Mantoux skin test was positive and a lumbar magnetic resonance imaging study showed a compression fracture of D4 vertebral body and soft-tissue abscess in L1. Microbiological examination was positive for M. tuberculosis complex, and with the diagnosis of Pott́s disease, he began treatment. With the advent of anti-tuberculosis drugs, spinal involvement of tuberculosis is rare, but it continues to have a high impact on morbidity. Treatment of vertebral involvement is based on anti-tuberculosis drugs and surgery.

Prevalence of hepatitis B virus infection among tuberculosis patients with or without HIV in Goiânia City, Brazil

BACKGROUND

Hepatitis B virus (HBV) and tuberculosis (TB) represent major public health problems. There is currently little data on HBV infection among TB patients with and without human immunodeficiency virus (HIV).

OBJECTIVES

To assess HBV prevalence among TB patients with and without HIV.

STUDY DESIGN

From April 2008 to March 2010, a cross-sectional study was conduct among TB patients attended at a reference hospital in Goiânia City, Brazil. The participants were tested for serological markers of HBV infection and HIV antibodies. HBV DNA was detected in HBsAg-positive samples, and also in HBsAg-negative/anti-HBc-positive samples to look for HBV occult infection.

RESULTS

Of 425 patients, 402 (94.6%) agreed to participate in the study. The overall prevalence of HBV (HBsAg and/or anti-HBc positive) and HIV infections were 25.6% (103/402) and 27.6% (111/402), respectively. A higher HBV infection rate was found among HIV-infected patients (36.9%; 41/111) compared to patients infected with TB only (20.0%; 57/285). A multivariate analysis of risk factors showed that age ≥ 50 years (p=0.03), non-injecting (p<0.01) and injecting (p<0.01) drugs use were associated with HBV infection. Among the HBsAg-positive samples (n=13), HBV DNA was detected in 10 (76.9%) samples. Of the 90 anti-HBc-positive samples, 13 were HBV DNA positive (with very low levels) resulting in an occult HBV infection rate of 14.4%. PCR-RFLP was successfully performed in 20 HBV DNA-positive samples: 15 were genotype A and 5 were genotype D.

CONCLUSIONS

HBV infection was common, particularly among this with HIV infection.

Evolution of antiretroviral drug costs in Brazil in the context of free and universal access to AIDS treatment

BACKGROUND

Little is known about the long-term drug costs associated with treating AIDS in developing countries. Brazil's AIDS treatment program has been cited widely as the developing world's largest and most successful AIDS treatment program. The program guarantees free access to highly active antiretroviral therapy (HAART) for all people living with HIV/AIDS in need of treatment. Brazil produces non-patented generic antiretroviral drugs (ARVs), procures many patented ARVs with negotiated price reductions, and recently issued a compulsory license to import one patented ARV. In this study, we investigate the drivers of recent ARV cost trends in Brazil through analysis of drug-specific prices and expenditures between 2001 and 2005.

METHODS AND FINDINGS

We compared Brazil's ARV prices to those in other low- and middle-income countries. We analyzed trends in drug expenditures for HAART in Brazil from 2001 to 2005 on the basis of cost data disaggregated by each ARV purchased by the Brazilian program. We decomposed the overall changes in expenditures to compare the relative impacts of changes in drug prices and drug purchase quantities. We also estimated the excess costs attributable to the difference between prices for generics in Brazil and the lowest global prices for these drugs. Finally, we estimated the savings attributable to Brazil's reduced prices for patented drugs. Negotiated drug prices in Brazil are lowest for patented ARVs for which generic competition is emerging. In recent years, the prices for efavirenz and lopinavir-ritonavir (lopinavir/r) have been lower in Brazil than in other middle-income countries. In contrast, the price of tenofovir is US$200 higher per patient per year than that reported in other middle-income countries. Despite precipitous price declines for four patented ARVs, total Brazilian drug expenditures doubled, to reach US$414 million in 2005. We find that the major driver of cost increases was increased purchase quantities of six specific drugs: patented lopinavir/r, efavirenz, tenofovir, atazanavir, enfuvirtide, and a locally produced generic, fixed-dose combination of zidovudine and lamivudine (AZT/3TC). Because prices declined for many of the patented drugs that constitute the largest share of drug costs, nearly the entire increase in overall drug expenditures between 2001 and 2005 is attributable to increases in drug quantities. Had all drug quantities been held constant from 2001 until 2005 (or for those drugs entering treatment guidelines after 2001, held constant between the year of introduction and 2005), total costs would have increased by only an estimated US$7 million. We estimate that in the absence of price declines for patented drugs, Brazil would have spent a cumulative total of US$2 billion on drugs for HAART between 2001 and 2005, implying a savings of US$1.2 billion from price declines. Finally, in comparing Brazilian prices for locally produced generic ARVs to the lowest international prices meeting global pharmaceutical quality standards, we find that current prices for Brazil's locally produced generics are generally much higher than corresponding global prices, and note that these prices have risen in Brazil while declining globally. We estimate the excess costs of Brazil's locally produced generics totaled US$110 million from 2001 to 2005.

CONCLUSIONS

Despite Brazil's more costly generic ARVs, the net result of ARV price changes has been a cost savings of approximately US$1 billion since 2001. HAART costs have nevertheless risen steeply as Brazil has scaled up treatment. These trends may foreshadow future AIDS treatment cost trends in other developing countries as more people start treatment, AIDS patients live longer and move from first-line to second and third-line treatment, AIDS treatment becomes more complex, generic competition emerges, and newer patented drugs become available. The specific application of the Brazilian model to other countries will depend, however, on the strength of their health systems, intellectual property regulations, epidemiological profiles, AIDS treatment guidelines, and differing capacities to produce drugs locally.

The search for a tuberculosis vaccine: An elusive quest?

The precise mechanisms of protective immunity and pathogenesis of tuberculosis (TB) are poorly understood. Yet, many efforts are underway to develop new, more effective vaccines against Mycobacterium tuberculosis. This development appears to be predicated upon the assumption that natural acquired immunity to TB exists. In this paper we review the evidence for such immunity, explore the hypothesis that disease progression is due to some, often transient, immunological dysfunction, and discuss its relevance for vaccine development. Several mechanisms for such an immune dysfunction are proposed, including the recently suggested involvement of viral co-infections. Developing vaccines for such co-infections may be a new challenge for TB control.