Latent TB and depressive symptoms in household contacts of persons with active TB

BACKGROUND: Depression is common among persons with TB and is associated with poor clinical outcomes. However, little is known about the relationship between latent TB infection (LTBI) and depression. We assessed the association between LTBI and depressive symptoms among household contacts (HHCs) of patients receiving TB treatment.METHODS: We enrolled 1,009 HHCs of 307 patients receiving TB treatment in Lima, Peru, during 2016-2018. At enrollment, HHC LTBI status was assessed using the interferon-gamma release assay (IGRA). Depressive symptoms were assessed at baseline and 12 months later using the Patient Health Questionnaire-9 (PHQ-9) with a cut-off of ≥5. We used logistic regression to estimate the odds ratio (OR) for PHQ-9 ≥5, comparing HHCs with and without baseline LTBI.RESULTS: Among 921 HHCs, 374 (41.0%) had LTBI at baseline, and 69 (12.4%) of 567 HHCs had PHQ-9 ≥5. Compared to HHCs without LTBI at enrollment, those with LTBI had almost two times the odds of PHQ-9 ≥5 at follow-up after controlling for potential confounders (adjusted OR 1.93, 95% CI 1.09-3.39); this association was driven by greater severities of depressive symptoms.CONCLUSION: HHCs with LTBI had increased odds of depressive symptoms 1 year later. This population may benefit from mental health screening and interventions integrated into TB programs.

Using the Food and Drug Administration´s Sentinel System for surveillance of TB infection

BACKGROUND: We examined patterns in care for individuals treated for latent TB infection (LTBI) in the US Food and Drug Administration´s Sentinel System.METHODS: Using administrative claims data, we identified patients who filled standard LTBI treatment prescriptions during 2008-2019. In these cohorts, we assessed LTBI testing, clinical management, and treatment duration.RESULTS: Among 113,338 patients who filled LTBI prescriptions, 80% (90,377) received isoniazid (INH) only, 19% (21,235) rifampin (RIF) only, and 2% (1,726) INH + rifapentine (RPT). By regimen, the proportion of patients with documented prior testing for TBI was 79%, 54%, and 91%, respectively. Median therapy duration was 84 days (IQR 35-84) for the 3-month once-weekly INH + RPT regimen, 60 days (IQR 30-100) for the 6- to 9-month INH regimen, and 30 days (IQR 2-60) for the 4-month RIF regimen.CONCLUSIONS: Among the cohorts, INH-only was the most commonly prescribed LTBI treatment. Most persons who filled a prescription for LTBI treatment did not have evidence of completing recommended treatment duration. These data further support preferential use of shorter-course regimens such as INH + RPT.

Impact of Latent Tuberculosis on Severity and Outcomes in Admitted COVID-19 Patients

Background

There is limited data on coronavirus disease 2019 (COVID-19) and latent tuberculosis infection (LTBI).

Methodology

We analyzed data of admitted COVID-19 patients evaluated for LTBI to examine the impact of LTBI on severity, laboratory parameters, and COVID-19 outcome. Prospectively collected data were analyzed for 60 patients who were administered the Mantoux tuberculosis skin test (TST) using five tuberculin units of purified protein derivative. All patients were administered TST irrespective of Bacille Calmette-Guérin (BCG) vaccination status. Comorbidities, clinical features, radiologic involvement, laboratory parameters, and clinical course were analyzed concerning LTBI.

Results

The mean age was 45.9 (±15.2) years, and 35 (58.3%) patients had non-severe disease. The vast majority (n = 56/60; 93.3%) had been vaccinated with single-dose BCG in infancy or early childhood, as per national immunization guidelines. LTBI was diagnosed in 15 (25%) patients. LTBI prevalence was lower in severe (n = 1/25; 4%) than non-severe (n = 14/35; 40%) COVID-19 (p = 0.01) patients. LTBI patients had lower percentage neutrophil count, higher lymphocyte percentage, higher monocyte count, lower neutrophil-lymphocyte (NL) ratio, lower alanine aminotransferase, lower C-reactive protein, and lesser radiologic involvement compared to those without LTBI (p < 0.05). Similarly, among the mild COVID-19 subgroup, those with LTBI had higher lymphocyte and monocyte counts and lesser radiologic involvement than those without LTBI (p < 0.05).

Conclusions

LTBI patients appear to have milder disease, higher lymphocyte and monocyte count, higher NL ratio, and lesser radiographic involvement. This observation needs to be studied in larger studies using interferon release assays.

Brief Report: Yield of Repeat Tuberculin Skin Testing for People Living With HIV in Brazil

OBJECTIVES

In Brazil, annual tuberculin skin tests (TSTs) are recommended for people living with HIV (PLWH) with CD4 >350, with tuberculosis preventive therapy provided on test conversion. We aimed to determine the yield of repeat TSTs for PLWH.

DESIGN

Secondary analysis of the stepped-wedge, cluster-randomized THRio trial for isoniazid preventive therapy (IPT) to prevent tuberculosis (TB).

METHODS

We analyzed data from newly registered PLWH with negative baseline TST results. We calculated the number of TST conversions after 1 and/or 2 years among patients eligible for follow-up TSTs, the proportion of converters initiating IPT, and incidence of TB/death.

RESULTS

Among 1770 PLWH with a negative baseline TST, 679 (38%) were female and median age was 36 years (IQR 29-43). Eighty-six (5%) developed TB or died within 1 year. Among 1684 eligible for a follow-up 1-year TST, 582 (35%) were tested and 53 (9%) were positive. Forty-nine converters (92%) started IPT. Of 529 patients with a negative 1-year TST, 7 (1%) developed TB or died over the following year. Of 522 patients eligible for a 2-year TST, 158 (30%) were tested and 13 (8%) were positive. Ten converters (77%) started IPT. Of 1102 patients who did not receive a 1-year TST, 33 (3%) developed TB or died. Of the 1069 patients eligible for a 2-year TST, 259 (24%) were tested and 34 (13%) were positive. Thirty converters (88%) started IPT.

CONCLUSIONS

In this cohort of PLWH in Brazil, TST conversion was high among those retested, but only 48% received a follow-up TST within 2 years.

Factors Associated With Latent Tuberculosis Infection Treatment Failure Among Patients With Commercial Health Insurance-United States, 2005-2016

CONTEXT

Approximately 80% of US tuberculosis (TB) cases verified during 2015-2016 were attributed to untreated latent TB infection (LTBI). Identifying factors associated with LTBI treatment failure might improve treatment effectiveness.

OBJECTIVE

To identify patients with indicators of isoniazid (INH) LTBI treatment initiation, completion, and failure.

METHODS

We searched inpatient and outpatient claims for International Classification of Diseases (Ninth and Tenth Revisions), National Drug, and Current Procedural Terminology codes. We defined treatment completion as 180 days or more of INH therapy during a 9-month period. We defined LTBI treatment failure as an active TB disease diagnosis more than 1 year after starting LTBI treatment among completers and used exact logistic regression to model possible differences between groups. Among treatment completers, we matched 1 patient who failed treatment with 2 control subjects and fit regression models with covariates documented on medical claims paid 6 months or less before INH treatment initiation.

PARTICIPANTS

Commercially insured US patients in a large commercial database with insurance claims paid during 2005-2016.

MAIN OUTCOME MEASURES

(1) Trends in treatment completion; (2) odds ratios (ORs) for factors associated with treatment completion and treatment failure.

RESULTS

Of 21 510 persons who began LTBI therapy during 2005-2016, 10 725 (49.9%) completed therapy. Treatment noncompletion is associated with those younger than 45 years, living in the Northeast or South Census regions, and women. Among persons who completed treatment, 30 (0.3%) progressed to TB disease. Diagnoses of rheumatoid arthritis during the 6 months before treatment initiation and being aged 65 years or older (reference: ages 0-24 years) were significantly associated with INH LTBI treatment failure (adjusted exact OR = 5.1; 95% CI, 1.2-28.2; and adjusted exact OR = 5.1; 95% CI, 1.2-25.3, respectively).

CONCLUSION

Approximately 50% of persons completed INH LTBI therapy, and of those, treatment failure was associated with rheumatoid arthritis and persons 65 years or older among a cohort of US LTBI patients with commercial health insurance.

Adipokines and the risk of active TB: a nested case-control study

BACKGROUND: Adipokines are emerging mediators of immune response, and may affect susceptibility to active TB.OBJECTIVE: To examine the associations between adipokines and the risk of active TB.METHODS: In a case-control study nested within a prospective cohort of middle-aged and older adults in Singapore, 280 incident active TB cases who donated blood for research before diagnosis were matched with 280 controls. Serum levels of adiponectin, resistin, leptin and ghrelin were measured. Multivariable logistic regression models were used to compute the adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for the associations between adipokines and the risk of active TB.RESULTS: Higher levels of leptin and resistin were associated with reduced risk of TB in a dose-dependent manner. Compared to those in the lowest quartile of leptin levels, those in the highest quartile had an OR of 0.46 (95%CI 0.26-0.82; P for trend = 0.009). Similarly, compared to those in the lowest quartile of resistin levels, those in the highest quartile had an OR of 0.46 (95%CI 0.24-0.90; P for trend = 0.03). Adiponectin and ghrelin levels were not associated with TB risk.CONCLUSION: Increased serum levels of leptin and resistin may be associated with reduced susceptibility to active TB infection.

CD4+ cell count stratification to guide tuberculosis preventive therapy for people living with HIV

OBJECTIVES

In 2018, Brazilian guidelines changed to recommend tuberculosis (TB) preventive therapy for all people with HIV and a CD4 cell count 350 cells/μl or less, but only for those with a positive tuberculin skin test (TST) if CD4 cell count is than 350 cells/μl. We determined the potential effectiveness of CD4-based guidelines for TB testing and preventive therapy.

DESIGN

Secondary analysis of the stepped-wedge, cluster-randomized THRio trial for isoniazid preventive therapy (IPT).

METHODS

We analyzed data from 4114 newly registered patients with HIV in 29 clinics followed until TB diagnosis, death, or administrative censoring. We compared incidence rates of TB and TB/death between CD4, TST, IPT, and antiretroviral therapy categories.

RESULTS

Initial CD4 cell count was 350 cells/μl or less in 2138 (52%) and more than 350 cells/μl in 1976 (48%) patients. TST was performed for 2922 (71%), of whom 657 (16%) were TST-positive [278 (13%) CD4 ≤ 350 vs. 379 (19%) CD4 > 350]. A total of 619 (15%) received IPT and 2806 (68%) received antiretroviral therapy. For patients with CD4 cell count 350 cells/μl or less who did not receive IPT, the incidence rate of TB was 1.79/100 person-years (pys) and TB/death was 3.89/100 pys. For patients with CD4 cell count more than 350 who did not receive IPT, the incidence rates of TB and TB/death were 0.57/100 and 1.49/100 pys for TST-negatives, and 1.05/100 and 1.64/100 pys for TST-unknowns.

CONCLUSION

TB incidence was high among all patients who did not receive IPT, including those with CD4 cell count more than 350 cells/μl and negative or unknown TST results. TB preventive therapy should be provided to all people living with HIV in medium burden settings, regardless of CD4 cell count and TST status.

Improving Screening for Latent Tuberculosis Infection in a Student-run Free Clinic

Introduction

Latent tuberculosis infection (LTBI) screening with targeted treatment has been successful in eradicating tuberculosis (TB) as an endemic infection in the United States. The Centers for Disease Control and Prevention (CDC) recommends screening for high-risk patients. The aim of this study was to increase LTBI screening, detection, and treatment in our student-run free clinic while providing an innovative platform for education in primary care topics.

Methods

A questionnaire for screening for LTBI was adapted from CDC guidelines. Medical students and providers received education on the screening process and administered questionnaires to patients. We analyzed the rate of performed LTBI screening, the rate of diagnostic testing for patients with positive screening, and the feasibility of implementing a preventive screening initiative.

Results

Fifty-two patients completed primary care visits. Forty patients were screened for LTBI. Of those screened, 42.5% were positive for the screening. Of those with positive screening, 70.6% were followed up via diagnostic testing, with the rest of them being lost for follow-up due to not attending the clinic for care.

Conclusions

This educational intervention combined with a screening tool was effective in increasing LTBI screening rates amongst patients in a student-run free clinic.

Spatial clusters of latent tuberculous infection, Connecticut, 2010-2014

SETTING

In the United States, tuberculosis (TB) control is increasingly focusing on the identification of persons with latent tuberculous infection (LTBI).

OBJECTIVE

To characterize the local epidemiology of LTBI in Connecticut, USA.

METHODS

We used spatial analyses 1) to identify census tract-level clusters of reported LTBI and TB disease in Connecticut, 2) to compare persons and populations in clusters with those not in clusters, and 3) to compare persons with LTBI to those with TB disease.

RESULTS

Significant census tract-level spatial clusters of LTBI and TB disease were identified. Compared with persons with LTBI in non-clustered census tracts, those in clustered census tracts were more likely to be foreign-born and less likely to be of white non-Hispanic ethnicity. Populations in census tract clusters of high LTBI prevalence had greater crowding, persons living in poverty, and persons lacking health care insurance than populations not in clustered census tracts. Persons with LTBI were less likely than those with TB disease to be of Asian ethnicity, and persons with LTBI were more likely than those with TB disease to reside in a clustered census tract.

CONCLUSIONS

Characterizing fine-scale populations at risk for LTBI supports effective and culturally accessible screening and treatment programs.

Cost-effectiveness of a 12-dose regimen for treating latent tuberculous infection in the United States

SETTING

A large randomized controlled trial recently showed that for treating latent tuberculous infection (LTBI) in persons at high risk of progression to tuberculosis (TB) disease, a 12-dose regimen of weekly rifapentine plus isoniazid (3HP) administered as directly observed treatment (DOT) can be as effective as 9 months of daily self-administered isoniazid (9H).

OBJECTIVES

To assess the cost-effectiveness of 3HP compared to 9H.

DESIGN

A computational model was designed to simulate individuals with LTBI treated with 9H or 3HP. Costs and health outcomes were estimated to determine the incremental costs per active TB case prevented and per quality-adjusted life year (QALY) gained by 3HP compared to 9H.

RESULTS

Over a 20-year period, treatment of LTBI with 3HP rather than 9H resulted in 5.2 fewer cases of TB and 25 fewer lost QALYs per 1000 individuals treated. From the health system and societal perspectives, 3HP would cost respectively US$21,525 and $4294 more per TB case prevented, and respectively $4565 and $911 more per QALY gained.

CONCLUSIONS

3HP may be a cost-effective alternative to 9H, particularly if the cost of rifapentine decreases, the effectiveness of 3HP can be maintained without DOT, and 3HP treatment is limited to those with a high risk of progression to TB disease.

Isoniazid-resistant tuberculosis in children: a systematic review

BACKGROUND

Isoniazid resistance is an obstacle to the treatment of tuberculosis disease and latent tuberculosis infection in children. We aim to summarize the literature describing the risk of isoniazid-resistant tuberculosis among children with tuberculosis disease.

METHODS

We did a systematic review of published reports of children with tuberculosis disease who had isolates tested for susceptibility to isoniazid. We searched PubMed, Embase and LILACS online databases up to January 12, 2012.

RESULTS

Our search identified 3403 citations, of which 95 studies met inclusion criteria. These studies evaluated 8351 children with tuberculosis disease for resistance to isoniazid. The median proportion of children found to have isoniazid-resistant strains was 8%; the distribution was right-skewed (25th percentile: 0% and 75th percentile: 18%).

CONCLUSIONS

High proportions of isoniazid resistance among pediatric tuberculosis patients have been reported in many settings suggesting that diagnostics detecting only rifampin resistance are insufficient to guide appropriate treatment in this population. Many children are likely receiving substandard tuberculosis treatment with empirical isoniazid-based regimens, and treating latent tuberculosis infection with isoniazid may not be effective in large numbers of children. Work is needed urgently to identify effective regimens for the treatment of children sick with or exposed to isoniazid-resistant tuberculosis and to better understand the scope of this problem.

The reliability and practicality of the Arkansas method assay of isoniazid adherence

The Arkansas method (AM) for isoniazid (INH) metabolite detection is a relatively inexpensive, simple, objective measure of adherence. The purpose of the study was to explore whether variations in urine sample handling and storage will produce accurate assay outcomes. Participants were a convenience sample of 28 adults and adolescents prescribed INH for latent tuberculosis infection. Participants provided one sample to test effects of the following: mixing processes; durations at room temperature, in a refrigerator, or frozen; and effects of freeze/thaw cycles on AM outcomes. No manipulations had a discernible impact on outcomes with concordant positive rates from 85% to 100%. Concordance rates of manipulated samples did not appear to differ from rates of norm samples. Results suggest that urine samples can withstand a variety of manipulations in both handling and storage without affecting the accuracy of AM assay results. These findings have important implications for providers of treatment and researchers and provide the impetus for both to examine the potential of using the AM of INH metabolite testing as a measure of medication adherence.

Tuberculosis incidence among contacts of active pulmonary tuberculosis

BACKGROUND

Treatment of latent tuberculosis (TB) infection (LTBI) in Brazil is recommended only in the case of contacts of pulmonary smear-positive TB patients aged<or=15 years with a tuberculin skin test (TST)>or=10 mm and no previous bacille Calmette-Guérin (BCG) vaccination or with a TST>or=15 mm regardless of previous BCG vaccination.

OBJECTIVE

To evaluate the 2-year incidence and predictors of TB among contacts who did not meet the Brazilian criteria for LTBI treatment.

DESIGN

Retrospective cohort study. Contacts aged between 12 and 15 years and those aged>or=15 years who did not meet the Brazilian criteria for LTBI treatment were enrolled in the study.

RESULTS

TB incidence was 3.2% (22/667), with an estimated TB rate of 1649 per 100000 population. Risk of TB was greater among the 349 contacts with TST>or=5 mm (5.4%) compared to the 318 contacts with TST<5 mm (0.9%; RR 6.04, 95%CI 1.7-20.6).

CONCLUSION

The high incidence of TB among contacts who did not meet the Brazilian criteria for LTBI treatment strongly suggests that these criteria should be reviewed. Furthermore, even among BCG-vaccinated contacts, TST induration>or=5 mm was the only variable that predicted the development of TB disease within 2years.