Adherence to nine-month isoniazid for latent tuberculosis infection in healthcare workers: a prospective study in a tertiary hospital

Incidence of tuberculosis disease in individuals diagnosed with tuberculosis infection after screening: A population-based cohort study in South Korea

OBJECTIVES

Limited evidence exists regarding the impact of adherence to diverse tuberculosis (TB) preventive therapy (TPT) regimens on TB risk in individuals with TB infections (TBIs). This study aimed to examine the association between adherence to three TPT regimens and TB incidence.

METHODS

This population-based retrospective cohort study used South Korean national health insurance data to identify individuals who were newly diagnosed with TBI between 2015 and 2020. TB incidence was compared among the different TPT regimens used. Treatment adherence was evaluated using the medication possession ratio (MPR).

RESULTS

The study involved 220,483 individuals with TBI, with half undergoing TPT. Over a mean 3.17-year follow-up, 2,430 cases of active TB were observed. TPT was associated with a 14% reduction in TB incidence risk in the entire study population with varying levels of TB risk. Non-adherence (MPR <80%) rates were 36% for 9 months of treatment with isoniazid, 22% for 4 months of treatment with rifampicin, and 18% for 3 months of treatment with isoniazid and rifampicin. Non-adherence to TPT did not lead to a decrease in the risk of TB incidence, whereas adherence to TPT (MPR ≥80%) reduced the risk of TB incidence by up to 72%.

CONCLUSIONS

This study reveals increased adherence with shorter TPT regimens in a national TBI cohort, emphasizing the pivotal role of medication adherence in preventing TB.

Screening for latent tuberculosis in migrants-status quo and future challenges

OBJECTIVES

To review the evidence that migrants from tuberculosis (TB) high-incidence countries migrating to TB low-incidence countries significantly contribute to active TB cases in the counties of destination, primarily through reactivation of latent TB.

METHODS

This is a narrative review. The different screening programs in the countries of destination are reviewed either based on screening and preventive treatment of latent TB pre or more commonly - post arrival.

RESULTS

Screening can be performed using interferon-gamma release assays (IGRA) or tuberculin skin tests (TST). Preventive treatment of latent TB is using either monotherapy with isoniazid, or in combination with rifampicin or rifapentine. We discuss the ethical issues of preventive treatment in asymptomatic individuals and how these are addressed in different screening programs.

CONCLUSION

Screening migrants from TB high endemic countries to TB low endemic countries is beneficial. There is a lack of standardization and agreement on screening protocols, follow up and treatment.

Synergistic toxicity with copper contributes to NAT2-associated isoniazid toxicity

Anti-tuberculosis (AT) medications, including isoniazid (INH), can cause drug-induced liver injury (DILI), but the underlying mechanism remains unclear. In this study, we aimed to identify genetic factors that may increase the susceptibility of individuals to AT-DILI and to examine genetic interactions that may lead to isoniazid (INH)-induced hepatotoxicity. We performed a targeted sequencing analysis of 380 pharmacogenes in a discovery cohort of 112 patients (35 AT-DILI patients and 77 controls) receiving AT treatment for active tuberculosis. Pharmacogenome-wide association analysis was also conducted using 1048 population controls (Korea1K). NAT2 and ATP7B genotypes were analyzed in a replication cohort of 165 patients (37 AT-DILI patients and 128 controls) to validate the effects of both risk genotypes. NAT2 ultraslow acetylators (UAs) were found to have a greater risk of AT-DILI than other genotypes (odds ratio [OR] 5.6 [95% confidence interval; 2.5-13.2], P = 7.2 × 10-6). The presence of ATP7B gene 832R/R homozygosity (rs1061472) was found to co-occur with NAT2 UA in AT-DILI patients (P = 0.017) and to amplify the risk in NAT2 UA (OR 32.5 [4.5-1423], P = 7.5 × 10-6). In vitro experiments using human liver-derived cell lines (HepG2 and SNU387 cells) revealed toxic synergism between INH and Cu, which were strongly augmented in cells with defective NAT2 and ATP7B activity, leading to increased mitochondrial reactive oxygen species generation, mitochondrial dysfunction, DNA damage, and apoptosis. These findings link the co-occurrence of ATP7B and NAT2 genotypes to the risk of INH-induced hepatotoxicity, providing novel mechanistic insight into individual AT-DILI susceptibility. Yoon et al. showed that individuals who carry NAT2 UAs and ATP7B 832R/R genotypes are at increased risk of developing isoniazid hepatotoxicity, primarily due to the increased synergistic toxicity between isoniazid and copper, which exacerbates mitochondrial dysfunction-related apoptosis.

Isoniazid preventive therapy completion between July-September 2019: A comparison across HIV differentiated service delivery models in Uganda

BACKGROUND

Tuberculosis (TB) remains the leading cause of death among people living with HIV (PLHIV). To prevent TB among PLHIV, the Ugandan national guidelines recommend Isoniazid Preventive Therapy (IPT) across differentiated service delivery (DSD) models, an effective way of delivering ART. DSD models include Community Drug Distribution Point (CDDP), Community Client-led ART Delivery (CCLAD), Facility-Based Individual Management (FBIM), Facility-Based Group (FBG), and Fast Track Drug Refill (FTDR). Little is known about the impact of delivering IPT through DSD.

METHODS

We reviewed medical records of PLHIV who initiated IPT between June-September 2019 at TASO Soroti (TS), Katakwi Hospital (KH) and Soroti Regional Referral Hospital (SRRH). We defined IPT completion as completing a course of isoniazid within 6-9 months. We utilized a modified Poisson regression to compare IPT completion across DSD models and determine factors associated with IPT completion in each DSD model.

RESULTS

Data from 2968 PLHIV were reviewed (SRRH: 50.2%, TS: 25.8%, KH: 24.0%); females: 60.7%; first-line ART: 91.7%; and Integrase Strand Transfer Inhibitor (INSTI)-based regimen: 61.9%. At IPT initiation, the median age and duration on ART were 41.5 (interquartile range [IQR]; 32.3-50.2) and 6.0 (IQR: 3.7-8.6) years, respectively. IPT completion overall was 92.8% (95%CI: 91.8-93.7%); highest in CDDP (98.1%, 95%CI: 95.0-99.3%) and lowest in FBG (85.8%, 95%CI: 79.0-90.7%). Compared to FBIM, IPT completion was significantly higher in CDDP (adjusted rate ratio [aRR] = 1.15, 95%CI: 1.09-1.22) and CCLAD (aRR = 1.09, 95% CI 1.02-1.16). In facility-based models, IPT completion differed between sites (p<0.001). IPT completion increased with age for FBIM and CCLAD and was lower among female participants in the CCLAD (aRR = 0.82, 95%CI 0.67-0.97).

CONCLUSION

IPT completion was high overall but highest in community-based models. Our findings provide evidence that supports integration of IPT within DSD models for ART delivery in Uganda and similar settings.

Healthcare workers' acceptance of and adherence to latent tuberculosis treatment

BACKGROUND

Healthcare workers (HCWs) with latent tuberculosis infection (LTBI) have a high risk of active tuberculosis and need systematic LTBI screening and treatment. However, acceptance and adherence rates of LTBI treatment are low.

AIMS

To examine the specific reasons for the loss at each LTBI treatment-cascade stage: acceptance, continuation and completion of LTBI treatment in HCWs.

METHODS

This retrospective descriptive study was conducted among 61 HCWs with an interferon-gamma release assay-confirmed LTBI diagnosis who were prescribed LTBI treatment at a tertiary hospital in the Republic of Korea. Data were analysed using Pearson's chi-square, Fisher's exact, independent t-test and Mann-Whitney U-test. A word cloud analysis was used to describe the perceived meaning of LTBI in HCWs.

RESULTS

HCWs who refused or discontinued LTBI treatment perceived LTBI as 'not a big deal', whereas HCWs who completed LTBI treatment had a high-risk perception of the LTBI prognosis, such as 'frightened about adverse prognosis'. Determinants of non-adherence to the recommended LTBI treatment included a busy work schedule, side effects of anti-tuberculosis agents and the inconvenience of regularly taking anti-tuberculosis agents.

CONCLUSIONS

To ensure LTBI treatment adherence in HCWs, effective interventions that are customized to each stage of the LTBI treatment should be developed, with due consideration of the stage-specific perceived facilitators and barriers in the LTBI treatment cascade.

Challenges and the Way forward in Diagnosis and Treatment of Tuberculosis Infection

Globally, it is estimated that one-quarter of the world's population is latently infected with Mycobacterium tuberculosis (Mtb), also known as latent tuberculosis infection (LTBI). Recently, this condition has been referred to as tuberculosis infection (TBI), considering the dynamic spectrum of the infection, as 5-10% of the latently infected population will develop active TB (ATB). The chances of TBI development increase due to close contact with index TB patients. The emergence of multidrug-resistant TB (MDR-TB) and the risk of development of latent MDR-TB has further complicated the situation. Detection of TBI is challenging as the infected individual does not present symptoms. Currently, there is no gold standard for TBI diagnosis, and the only screening tests are tuberculin skin test (TST) and interferon gamma release assays (IGRAs). However, these tests have several limitations, including the inability to differentiate between ATB and TBI, false-positive results in BCG-vaccinated individuals (only for TST), false-negative results in children, elderly, and immunocompromised patients, and the inability to predict the progression to ATB, among others. Thus, new host markers and Mtb-specific antigens are being tested to develop new diagnostic methods. Besides screening, TBI therapy is a key intervention for TB control. However, the long-course treatment and associated side effects result in non-adherence to the treatment. Additionally, the latent MDR strains are not susceptible to the current TBI treatments, which add an additional challenge. This review discusses the current situation of TBI, as well as the challenges and efforts involved in its control.

Hepatotoxicity induced by isoniazid in patients with latent tuberculosis infection: a meta-analysis

Aim

The aim of the present study was to conduct a meta-analysis of the frequency of isoniazid-induced liver injury (INH-ILI) in patients receiving isoniazid (INH) preventative therapy (IPT).

Background

The frequency of hepatotoxicity (drug-induced liver injury: DILI) of antituberculosis drugs has been studied, especially when INH, rifampin, and pyrazinamide are co-administered. However, little is known about the frequency of DILI in patients with latent tuberculosis infection (LTBI), where IPT is indicated.

Methods

We searched PubMed, Google Scholar, and the Cochrane Database of Systematic Reviews for studies reporting the frequency of INH-ILI in patients with IPT using one or more diagnostic indicators included in the criteria of the DILI Expert Working Group.

Results

Thirty-five studies comprising a total of 22,193 participants were included. The overall average frequency of INH-ILI was 2.6% (95% CI, 1.7-3.7%). The mortality associated with INH-DILI was 0.02% (4/22193). Subgroup analysis revealed no significant differences in the frequency of INH-ILI in patients older or younger than 50 years, children, patients with HIV, candidates for liver, kidney, or lung transplant, or according to the type of study design.

Conclusion

The frequency of INH-ILI in patients receiving IPT is low. Studies on INH-ILI are needed where the current DILI criteria are used.

DISCOURSES OF HEALTH PROFESSIONALS ON LATENT TUBERCULOSIS INFECTION AND THE USE OF ISONIAZID

ABSTRACT Objective to understand the collective thinking and action of health workers in relation to Latent Tuberculosis Infection and its treatment with Isoniazid. Method qualitative study with 22 health professionals from four cities in Brazil and the Federal District. Data collection occurred through a semi-structured group interview in March 2019, with an average duration of one hour and thirty minutes. Content analysis was performed using the Collective Subject Discourse technique. Results the professionals' discourses revealed uncertainties related to the prevention and treatment of Latent Tuberculosis Infection, the "fear of error" and inadequate forms of use of Isoniazid 300 mg, the power of the decision on the treatment of Latent Tuberculosis Infection, the difficulties of integration between services and the organization of care flows. Conclusion although the emphasis in the professionals' discourse considers objective aspects in the management of Latent Tuberculosis Infection, subjective manifestations related to the need to address the fears that affect the decision about treatment and possible medication errors were identified, among others, and to think about this process in a collaborative way, which considers autonomy in acting, both of professionals and of the person with Latent Tuberculosis Infection.

DISCURSOS DE PROFISSIONAIS DE SAÚDE SOBRE INFECÇÃO LATENTE POR TUBERCULOSE E USO DE ISONIAZIDA

RESUMO Objetivo compreender o pensar e o agir coletivo de trabalhadores da saúde em relação à Infecção Latente por Tuberculose e ao uso da Isoniazida no enfrentamento da doença. Método estudo qualitativo com 22 profissionais de saúde de quatro cidades do Brasil e do Distrito Federal. A coleta de dados ocorreu mediante realização de entrevista coletiva semiestruturada, em março de 2019, com duração média de uma hora e trinta minutos. Realizou-se análise de conteúdo pela técnica do Discurso do Sujeito Coletivo. Resultados os discursos dos profissionais revelaram incertezas relacionadas à prevenção e ao tratamento da Infecção Latente por Tuberculose, ao “medo de errar” e formas inadequadas de uso da Isoniazida 300 mg, ao poder da decisão sobre o tratamento da Infecção Latente por Tuberculose, às dificuldades da integração entre os serviços e à organização de fluxos assistenciais. Conclusão embora a ênfase no discurso dos profissionais considere aspectos objetivos no manejo da Infecção Latente por Tuberculose, foram identificadas, dentre outras, manifestações subjetivas relacionadas à necessidade de trabalhar os receios que afetam a decisão sobre o tratamento e os possíveis erros de medicação, e de pensar esse processo de forma colaborativa, que considere autonomia no agir, tanto dos profissionais quanto da pessoa com Infecção Latente por Tuberculose.

Factors influencing the initiation and adherence of LTBI treatment in healthcare workers: a systematic review

Despite the importance of latent tuberculosis infection (LTBI) treatment and management in healthcare workers (HCWs), only a few studies have provided a comprehensive review of factors associated with the success rate of each stage of the LTBI treatment, as well as strategies to improve treatment adherence. This study investigated factors and determinants of patient losses at each stage of the entire cascade of LTBI in HCWs. Studies were extracted from PubMed, EBSCOhost, EMBASE, Cochrane Library, and ScienceDirect. Our study found poor completion rates of LTBI treatment in HCWs. The main reason for not visiting the outpatient clinic or not accepting treatment was related to the demographic characteristics, whereas adverse drug effects were the main reason for treatment discontinuation. These findings suggest that tailored interventions must be developed to improve the success rate at each stage of the LTBI treatment in HCWs.

Tuberculosis prevention in patients undergoing kidney transplantation: A nurse-led program for screening and treatment

BACKGROUND

Systematic screening for, and treatment of, latent tuberculosis (TB) infection is recommended prior to kidney transplant. However, little is known about patient compliance with, or the safety profile of, preventive therapies used in clinical practice.

METHODS

This was a retrospective observational study of patients who were eligible for kidney transplant and were evaluated for TB infection between January 2013 and June 2019 at the TB clinic of a tertiary care teaching hospital. All patient data were registered prospectively as part of our nurse-led program before kidney transplant. We assessed completion rates, tolerance with therapy, development of TB, and associated workload.

RESULTS

In total, 1568 patients were referred to our TB clinic for evaluation. Preventive therapy was given to 385 patients and completed by 340 (88.3%). Of these, 89 (23.1%) experienced some intolerance, with 27 requiring full discontinuation. After a median follow-up of 45 months (1426 patient-years), 206 (53.5%) of the treated patients received a kidney transplant; only one patient, who failed to complete treatment, developed post-transplant TB (7.01 cases per 10 000 patient-years; 95% confidence interval, 0.35-34.59). Extra nurse or medical visits were required by 268 (69.6%) patients.

CONCLUSION

Despite the complexity and workload generated by patients with ESRD awaiting kidney transplant, preventive therapy for TB is effective in most cases. Our experience provides important evidence on the feasibility of preventive therapy for TB before kidney transplant when delivered as part of a comprehensive nurse-led program.

Chest Radiographs and CT Findings during Healthcare Workers' Tuberculosis Screening Using Interferon-Gamma Release Assay: Retrospective Observational Study

Purpose

To investigate the incidence of tuberculosis (TB) in healthcare workers (HCWs) with positive interferon-gamma release assay (IGRA) results based on chest X-ray (CXR) and CT findings and determine the role of imaging in the diagnosis of TB.

Materials and Methods

Among 1976 hospital personnel screened for TB using IGRA, IGRA-positive subjects were retrospectively investigated. Clustered nodular and/or linear streaky opacities in the upper lung zone were considered positive on CXR. The CT findings were classified as active, indeterminate, inactive, or normal. The active or indeterminate class was considered CT-positive.

Results

IGRA was positive in 255 subjects (12.9%). CXR and CT were performed in 249 (99.2%) and 113 subjects (45.0%), respectively. CXR- and CT-positive findings were found in 7 of 249 (2.8%) and 9 of 113 (8.0%) patients, respectively. Among the nine CT-positive subjects, active and indeterminate TB findings were found in 6 (5.3%) and 3 (2.7%) patients, respectively. Microbiological tests, including acid-fast bacilli staining, culture, and polymerase chain reaction for TB, were negative in all nine CT-positive subjects. Empirical anti-TB medications were administered to 9 CT-positive subjects, and 3 of these nine subjects were CXR-negative for pulmonary TB.

Conclusion

CT helped diagnose asymptomatic TB in IGRA-positive HCWs.