A Step toward Tuberculosis Elimination in a Low-Incidence Country: Successful Diagnosis and Treatment of Latent Tuberculosis Infection in a Refugee Clinic

Objectives.Approximately 65 percent of tuberculosis (TB) cases in Canada each year occur from reactivation in foreign-born individuals. Refugees are at high risk after immigration. Routine screening of this population for latent TB infection (LTBI) is generally considered infeasible. We evaluated the outcome of LTBI screening and treatment amongst refugees.Methods.Government-sponsored refugees in Edmonton are seen at the New Canadians’ Clinic and screened for TB and LTBI. We reviewed records of patients between 2009 and 2011. Completeness of initial assessment, diagnosis of latent infection, and completion of LTBI treatment were evaluated. Treatment for LTBI was offered when patients had a positive Tuberculin Skin Test (TST) and risk factors for progression to TB. An Interferon-Gamma Release Assay (IGRA) was performed on all other TST positives; treatment is only offered if it was positive.Results.949 refugees were evaluated. 746 TSTs were read, with 265 positive individuals. IGRA testing was performed in 203 TST positive individuals without other TB risk factors; 110 were positive. LTBI treatment was offered to 147 of 151 eligible patients, 141 accepted, and 103 completed a treatment course.Conclusion.We observed high proportions of patient retention, completion of investigations, and treatment. This care model promises to be a component of effective TB prevention in this high-risk population.

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Interferon-gamma release assays for latent tuberculosis infection screening in Canadian federal correctional facilities

The International Journal of Tuberculosis and Lung Disease ◽

10.5588/ijtld.20.0801 ◽

2021 ◽

Vol 25 (6) ◽

pp. 447-452

Author(s):

A. Agostinis ◽

C. Heffernan ◽

R. Long ◽

A. Beckon ◽

S. Cockburn ◽

...

Keyword(s):

Interferon Gamma ◽

Latent Tuberculosis ◽

Interferon Gamma Release Assay ◽

Foreign Born ◽

Correctional Setting ◽

Ltbi Treatment ◽

Factors Associated ◽

Vaccination History ◽

Risk Of Disease ◽

Latent Tb Infection

BACKGROUND: The correctional setting presents an opportunity for latent TB infection (LTBI) screening in an otherwise difficult to reach demographic. We evaluate factors associated with the fidelity of the tuberculin skin test (TST) and interferon-gamma release assay (IGRA), specifically the QuantiFERON®-TB Gold In-Tube assay (QFT-GIT), explain factors associated with discordance, and report LTBI treatment outcomes.METHODS: We describe the association between demographic and clinical variables, and predictors of concordance with IGRA using univariate logistic regression in a population of TST-positive inmates. We report outcomes among those offered LTBI treatment.RESULTS: We observed concordance between TST and QFT-GIT in 90 of 306 (29.4%) inmates. Persons with TST+/QFT-GIT+ results were less likely to be male (OR 3.94, 95% CI 1.73–8.97) or have a BCG vaccination history (OR 0.34, 95% CI 0.12–0.95), and more likely to be foreign-born (P < 0.001). Of the 108 inmates offered LTBI treatment, 65 (60.1%) accepted and 51 (78.0%) completed. TST/QFT-GIT discordance has not been associated with disease during follow-up.CONCLUSION: Our findings suggest that TST/QFT-GIT discordance in Canadian federal inmates is common; however, low-risk of disease progression in those with discordance suggests that a shift towards IGRA-based screening is warranted and feasible.

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Trend and treatment outcomes of latent tuberculosis infection among migrant persons in Japan: retrospective analysis of Japan tuberculosis surveillance data

BMC Infectious Diseases ◽

10.1186/s12879-020-05712-1 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Lisa Kawatsu ◽

Kazuhiro Uchimura ◽

Akihiro Ohkado

Keyword(s):

Risk Factors ◽

Surveillance System ◽

Latent Tuberculosis Infection ◽

Latent Tuberculosis ◽

Migrant Population ◽

Foreign Born ◽

Ltbi Treatment ◽

Potential Risk Factors ◽

Lost To Follow Up

Abstract Background Screening for latent tuberculosis infection (LTBI) among migrant population has become a critical issue for many low tuberculosis (TB) burden countries. Evidence regarding effectiveness of LTBI programs are limited, however, partly because of paucity of national data on treatment outcomes for LTBI. In Japan, notification of LTBI is mandatory, and its treatment outcome is reported as part of Japan’s national TB surveillance system. We thus conducted a detailed analysis of LTBI among foreign-born persons, to update the epidemiological trend of newly notified LTBI between 2007 and 2018, and to examine the treatment regimen and outcome of those notified in 2016 and 2017, focusing specifically on the potential risk factors for lost to follow-up. Methods We extracted and analyzed the data of newly notified LTBI patients from the Japan Tuberculosis Surveillance System to examine the overall trend of notification and by age groups and modes of detection between 2007 and 2018, and the cohort data for treatment regimen and outcomes of foreign-born persons notified with LTBI in 2016 and 2017. Trends and proportions were summarized descriptively, and logistic regression analysis was conducted to identify potential risk factors for lost to follow-up. Comparisons were made with the Japan-born patients where appropriate, using chi-squared tests. Results Both the number and proportion of LTBI among foreign-born persons have been constantly increasing, reaching 963 cases in 2018. Cohort analysis of the surveillance data indicated that the proportion of those on shorter regimen was higher among the foreign- than Japan-born patients (5.5% vs. 1.8%, p < 0.001). The proportion of those who have been lost to follow-up and transferred outside of Japan combined was higher among the foreign- than Japan-born patients (12.0% vs, 8.2%, p < 0.001). Risk factors for lost to follow-up were being employed on a temporal basis, and job status unknown (adjusted odds ratios 3.11 and 4.09, 95% confidence intervals 1.34–7.26 and 1.60–10.48, respectively). Conclusions Migrant population face greater risk of interrupting LTBI treatment, and interventions to improve adherence are a critical component of programmatic management of LTBI. Further studies are needed to explore the cultural and socioeconomic situation in which foreign-born persons undergo LTBI treatment in Japan.

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A Survey of Latent Tuberculosis Infection Among Laboratory Healthcare Workers in New York City

Infection Control and Hospital Epidemiology ◽

10.1086/502140 ◽

2003 ◽

Vol 24 (11) ◽

pp. 801-806 ◽

Cited By ~ 11

Author(s):

Elizabeth Garber ◽

Pablo San Gabriel ◽

Lauren Lambert ◽

Lisa Saiman

Keyword(s):

Risk Factors ◽

New York ◽

New York City ◽

York City ◽

Latent Tuberculosis ◽

Skin Tests ◽

First Year ◽

Foreign Born ◽

History Of ◽

Latent Tb Infection

AbstractObjective:To determine the prevalence of positive tuberculin skin tests (TSTs), incidence of TST conversion, risk factors for positive TSTs, and history of active TB among HCWs in microbiology laboratories in New York City.Design:Two-year survey from May 1999 to June 2001.Setting:Nineteen microbiology laboratories.Results:During the first year, interviews were conducted with 345 laboratory HCWs (mean, 18 HCWs per site; range, 2 to 51) to assess the prevalence of positive TSTs, but 3 (1%) could not recall their result and were excluded from further analyses. The mean age of the remaining 342 HCWs was 48 years; 68% (n = 233) were female, 54% (n = 183) received bacille Calmette-Guérin (BCG) vaccination, and 71% (n = 244) were foreign born. The prevalence of a positive TST was 57% (n = 196), but only 20% (n = 39) of the HCWs received isoniazid. The incidence of TST conversion in the second year of the study was 1% (1 of 108). Multivariate analysis identified age (odds ratio [OR] per year, 1.05; 95% confidence interval [CI95], 1.02–1.08), foreign birth (OR, 3.80; CI95, 1.98–7.28), BCG immunization (OR, 4.89; CI95, 2.72–8.80), and employment in a mycobacteriology laboratory (OR, 2.14; CI95, 1.25–3.68) as risk factors for a positive TST. Only one HCW had been treated for active TB.Conclusions:The prevalence of positive TSTs was high among laboratory HCWs, but the TST conversion rate was low. Higher rates of treatment for latent TB infection are desirable.

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Risk Factors for Tuberculosis and Effect of Preventive Therapy Among Close Contacts of Persons With Infectious Tuberculosis

Clinical Infectious Diseases ◽

10.1093/cid/ciz438 ◽

2019 ◽

Vol 70 (8) ◽

pp. 1562-1572 ◽

Cited By ~ 5

Author(s):

Mary R Reichler ◽

Awal Khan ◽

Timothy R Sterling ◽

Hui Zhao ◽

Bin Chen ◽

...

Keyword(s):

Risk Factors ◽

Skin Test ◽

Index Patient ◽

Preventive Therapy ◽

Patient Contact ◽

Foreign Born ◽

Ltbi Treatment ◽

Increased Risk ◽

Latent Tb Infection ◽

Close Contacts

Abstract Background Close contacts of persons with pulmonary tuberculosis (TB) have high rates of TB disease. Methods We prospectively enrolled TB patients and their close contacts at 9 US/Canadian sites. TB patients and contacts were interviewed to identify index patient, contact, and exposure risk factors for TB. Contacts were evaluated for latent TB infection (LTBI) and TB, and the effectiveness of LTBI treatment for preventing contact TB was examined. Results Among 4490 close contacts, multivariable risk factors for TB were age ≤5 years, US/Canadian birth, human immunodeficiency virus infection, skin test induration ≥10 mm, shared bedroom with an index patient, exposure to more than 1 index patient, and index patient weight loss (P < .05 for each). Of 1406 skin test–positive contacts, TB developed in 49 (9.8%) of 446 who did not initiate treatment, 8 (1.8%) of 443 who received partial treatment, and 1 (0.2%) of 517 who completed treatment (1951, 290, and 31 cases/100 000 person-years, respectively; P < .001). TB was diagnosed in 4.2% of US/Canadian-born compared with 2.3% of foreign-born contacts (P = .002), and TB rates for US/Canadian-born and foreign-born contacts who did not initiate treatment were 3592 and 811 per 100 000 person-years, respectively (P < .001). Conclusions Treatment for LTBI was highly effective in preventing TB among close contacts of infectious TB patients. Several index patient, contact, and exposure characteristics associated with increased risk of contact TB were identified. These findings help inform contact investigation, LTBI treatment, and other public health prevention efforts.

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Trend and treatment outcomes of latent tuberculosis infection among migrant persons in Japan: retrospective analysis of Japan Tuberculosis Surveillance data

10.21203/rs.3.rs-44087/v3 ◽

2020 ◽

Author(s):

Lisa Kawatsu ◽

Kazuhiro Uchimura ◽

Akihiro Ohkado

Keyword(s):

Risk Factors ◽

Surveillance System ◽

Latent Tuberculosis Infection ◽

Latent Tuberculosis ◽

Migrant Population ◽

Foreign Born ◽

Ltbi Treatment ◽

Potential Risk Factors ◽

Lost To Follow Up

Abstract Background: Screening for latent tuberculosis infection (LTBI) among migrant population has become a critical issue for many low tuberculosis (TB) burden countries. Evidence regarding effectiveness of LTBI programs are limited, however, partly because of paucity of national data on treatment outcomes for LTBI. In Japan, notification of LTBI is mandatory, and its treatment outcome is reported as part of Japan’s national TB surveillance system. We thus conducted a detailed analysis of LTBI among foreign-born persons, to update the epidemiological trend of newly notified LTBI between 2007 and 2018, and to examine the treatment regimen and outcome of those notified in 2016 and 2017, focusing specifically on the potential risk factors for lost to follow-up. Methods: We extracted and analyzed the data of newly notified LTBI patients from the Japan Tuberculosis Surveillance System to examine the overall trend of notification and by age groups and modes of detection between 2007 and 2018, and the cohort data for treatment regimen and outcomes of foreign-born persons notified with LTBI in 2016 and 2017. Trends and proportions were summarized descriptively, and logistic regression analysis was conducted to identify potential risk factors for lost to follow-up. Comparisons were made with the Japan-born patients where appropriate. Results: Both the number and proportion of LTBI among foreign-born persons have been constantly increasing, reaching 963 cases in 2018. Analysis of cohort data indicated that the proportion of those on shorter regimen was higher among the foreign- than Japan-born patients (5.5% vs. 1.8%, p<0.001). The proportion of those who have been lost to follow-up and transferred outside of Japan combined was higher among the foreign- than Japan-born patients (12.0% vs, 8.2%, p<0.001). Risk factors for lost to follow-up were being employed on a temporal basis, and job status unknown (adjusted odds ratios 3.11 and 4.09, 95% confidence intervals 1.34-7.26 and 1.60-10.48, respectively). Conclusions: Migrant population face greater risk of interrupting LTBI treatment, and interventions to improve adherence are a critical component of programmatic management of LTBI. Further studies are needed to explore the cultural and socioeconomic situation in which foreign-born persons undergo LTBI treatment in Japan.

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Trend and treatment outcomes of latent tuberculosis infection among migrant persons in Japan: retrospective analysis of Japan Tuberculosis Surveillance data

10.21203/rs.3.rs-44087/v2 ◽

2020 ◽

Author(s):

Lisa Kawatsu ◽

Kazuhiro Uchimura ◽

Akihiro Ohkado

Keyword(s):

Risk Factors ◽

Surveillance System ◽

Latent Tuberculosis Infection ◽

Latent Tuberculosis ◽

Migrant Population ◽

Foreign Born ◽

Ltbi Treatment ◽

Potential Risk Factors ◽

Lost To Follow Up

Abstract Background: Screening for latent tuberculosis infection (LTBI) among migrant population has become a critical issue for many low tuberculosis (TB) burden countries. Evidence regarding effectiveness of LTBI programs are limited, however, partly because of paucity of national data on treatment outcomes for LTBI. In Japan, notification of LTBI is mandatory, and its treatment outcome is reported as part of Japan’s national TB surveillance system. We thus conducted a detailed analysis of LTBI among foreign-born persons, to update the epidemiological trend of newly notified LTBI between 2007 and 2018, and to examine the treatment regimen and outcome of those notified in 2016 and 2017, focusing specifically on the potential risk factors for lost to follow-up.Methods: We extracted and analyzed the data of newly notified LTBI patients from the Japan Tuberculosis Surveillance System to examine the overall trend of notification and by age groups and modes of detection between 2007 and 2018, and the cohort data for treatment regimen and outcomes of foreign-born persons notified with LTBI in 2016 and 2017. Trends and proportions were summarized descriptively, and logistic regression analysis was conducted to identify potential risk factors for lost to follow-up. Comparisons were made with the Japan-born patients where appropriate.Results: Both the number and proportion of LTBI among foreign-born persons have been constantly increasing, reaching 963 cases in 2018. Analysis of cohort data indicated that the proportion of those on shorter regimen was higher among the foreign- than Japan-born patients (5.5% vs. 1.8%, p<0.001). The proportion of those who have been lost to follow-up and transferred outside of Japan combined was higher among the foreign- than Japan-born patients (12.0% vs, 8.2%, p<0.001). Risk factors for lost to follow-up were being employed on a temporal basis, and job status unknown (adjusted odds ratios 3.11 and 4.09, 95% confidence intervals 1.34-7.26 and 1.60-10.48, respectively).Conclusions: Migrant population face greater risk of interrupting LTBI treatment, and interventions to improve adherence are a critical component of programmatic management of LTBI. Further studies are needed to explore the cultural and socioeconomic situation in which foreign-born persons undergo LTBI treatment in Japan.

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Risk Factors for Indeterminate Outcome on Interferon Gamma Release Assay in Non-US-Born Persons Screened for Latent Tuberculosis Infection

Open Forum Infectious Diseases ◽

10.1093/ofid/ofy184 ◽

2018 ◽

Vol 5 (8) ◽

Cited By ~ 7

Author(s):

Jody C Sharninghausen ◽

Adrienne E Shapiro ◽

David M Koelle ◽

H Nina Kim

Keyword(s):

United States ◽

Risk Factors ◽

Interferon Gamma ◽

Multivariable Analysis ◽

Latent Tuberculosis ◽

The United States ◽

Interferon Gamma Release Assay ◽

Foreign Born ◽

Asian Race ◽

Release Assay

Abstract Background Non-US-born individuals account for the majority of active tuberculosis (TB) in the United States. Interferon gamma release assay (IGRA) is the preferred diagnostic test for latent TB but can produce an indeterminate result. We investigated the prevalence and predictors of an indeterminate IGRA (IND-IGRA) in a diverse cohort of non-US-born individuals and evaluated outcomes after IND-IGRA. Methods We identified patient age ≥18 years who had an outpatient IGRA between 2010 and 2017 in our health system and whose primary language was not English. We used univariate and multivariable logistic regression to examine the association of IND-IGRA with a variety of clinical factors. Results Of 3128 outpatients with ≥1 IGRA done, 33% were Asian, 30% Hispanic, and 29% black; 44% were men, and the median age was 50 years. An initial IND-IGRA occurred in 118 (3.8%; 95% confidence interval [CI], 3.1%–4.5%); notably, Asian race (55%) and rheumatologic conditions (25%) were prevalent in this group. In multivariable analysis, Asian race was independently associated with IND-IGRA (adjusted odds ratio [aOR], 2.9; 95% CI, 1.9–4.3), in addition to the presence of anemia and hypoalbuminemia (aOR for interaction, 4.3; 95% CI, 1.3–14.3). Only 55% of patients with an initial IND-IGRA underwent repeat testing; of those who did, 66% had a determinate result. Conclusions Asian race and anemia/hypoalbuminemia were independent risk factors for an indeterminate IGRA outcome in foreign-born patients screened in the United States. Our study underscores the importance of following through on indeterminate results in these key subgroups.

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Trend and treatment outcomes of latent tuberculosis infection among migrant persons in Japan: retrospective analysis of Japan Tuberculosis Surveillance data

10.21203/rs.3.rs-44087/v4 ◽

2020 ◽

Author(s):

Lisa Kawatsu ◽

Kazuhiro Uchimura ◽

Akihiro Ohkado

Keyword(s):

Risk Factors ◽

Surveillance System ◽

Latent Tuberculosis Infection ◽

Latent Tuberculosis ◽

Migrant Population ◽

Foreign Born ◽

Ltbi Treatment ◽

Potential Risk Factors ◽

Lost To Follow Up

Abstract Background: Screening for latent tuberculosis infection (LTBI) among migrant population has become a critical issue for many low tuberculosis (TB) burden countries. Evidence regarding effectiveness of LTBI programs are limited, however, partly because of paucity of national data on treatment outcomes for LTBI. In Japan, notification of LTBI is mandatory, and its treatment outcome is reported as part of Japan’s national TB surveillance system. We thus conducted a detailed analysis of LTBI among foreign-born persons, to update the epidemiological trend of newly notified LTBI between 2007 and 2018, and to examine the treatment regimen and outcome of those notified in 2016 and 2017, focusing specifically on the potential risk factors for lost to follow-up. Methods: We extracted and analyzed the data of newly notified LTBI patients from the Japan Tuberculosis Surveillance System to examine the overall trend of notification and by age groups and modes of detection between 2007 and 2018, and the cohort data for treatment regimen and outcomes of foreign-born persons notified with LTBI in 2016 and 2017. Trends and proportions were summarized descriptively, and logistic regression analysis was conducted to identify potential risk factors for lost to follow-up. Comparisons were made with the Japan-born patients where appropriate, using chi-squared tests. Results: Both the number and proportion of LTBI among foreign-born persons have been constantly increasing, reaching 963 cases in 2018. Cohort analysis of the surveillance data indicated that the proportion of those on shorter regimen was higher among the foreign- than Japan-born patients (5.5% vs. 1.8%, p<0.001). The proportion of those who have been lost to follow-up and transferred outside of Japan combined was higher among the foreign- than Japan-born patients (12.0% vs, 8.2%, p<0.001). Risk factors for lost to follow-up were being employed on a temporal basis, and job status unknown (adjusted odds ratios 3.11 and 4.09, 95% confidence intervals 1.34-7.26 and 1.60-10.48, respectively). Conclusions: Migrant population face greater risk of interrupting LTBI treatment, and interventions to improve adherence are a critical component of programmatic management of LTBI. Further studies are needed to explore the cultural and socioeconomic situation in which foreign-born persons undergo LTBI treatment in Japan.

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Effect of diabetes mellitus on risk of latent TB infection in a high TB incidence area: a community-based study in Taiwan

BMJ Open ◽

10.1136/bmjopen-2019-029948 ◽

2019 ◽

Vol 9 (10) ◽

pp. e029948

Author(s):

Ching-Hsiung Lin ◽

Shu-Chen Kuo ◽

Ming-Chia Hsieh ◽

Shang-Yun Ho ◽

Ih-Jen Su ◽

...

Keyword(s):

Risk Factors ◽

Latent Tuberculosis ◽

Risk Groups ◽

Secondary Outcome ◽

Interferon Gamma Release Assay ◽

Community Based ◽

Increased Risk ◽

Patients With Diabetes ◽

History Of ◽

Latent Tb Infection

ObjectiveTo investigate the association between diabetes and latent tuberculosis infections (LTBI) in high TB incidence areas.DesignCommunity-based comparison study.SettingOutpatient diabetes clinics at 4 hospitals and 13 health centres in urban and rural townships. A community-based screening programme was used to recruit non-diabetic participants.ParticipantsA total of 2948 patients with diabetes aged older than 40 years were recruited, and 453 non-diabetic participants from the community were enrolled.Primary and secondary outcome measuresThe interferon-gamma release assay (IGRA) and the tuberculin skin test were used to detect LTBI. The IGRA result was used as a surrogate of LTBI in logistic regression analysis.ResultsDiabetes was significantly associated with LTBI (adjusted OR (aOR)=1.59; 95% CI 1.11 to 2.28) and age correlated positively with LTBI. Many subjects with diabetes also had additional risk factors (current smokers (aOR=1.28; 95% CI 0.95 to 1.71), comorbid chronic kidney disease (aOR=1.26; 95% CI 1.03 to 1.55) and history of TB (aOR=2.08; 95% CI 1.19 to 3.63)). The presence of BCG scar was protective (aOR=0.66; 95% CI 0.51 to 0.85). Duration of diabetes and poor glycaemic control were unrelated to the risk of LTBI.ConclusionThere was a moderately increased risk of LTBI in patients with diabetes from this high TB incidence area. This finding suggests LTBI screening for the diabetics be combined with other risk factors and comorbidities of TB to better identify high-risk groups and improve the efficacy of targeted screening for LTBI.

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A cost-effectiveness study of tuberculosis and latent tuberculosis infection screening in prisons in Japan

The International Journal of Tuberculosis and Lung Disease ◽

10.5588/ijtld.19.0448 ◽

2020 ◽

Vol 24 (5) ◽

pp. 506-511

Author(s):

L. Kawatsu ◽

K. Uchimura ◽

A. Ohkado

Keyword(s):

Cost Effectiveness ◽

Latent Tuberculosis ◽

Cost Effective ◽

Transmission Model ◽

Interferon Gamma Release Assay ◽

High Risk Population ◽

Prison Inmates ◽

Screening Policy ◽

Latent Tb Infection ◽

The Cost

BACKGROUND: Prison inmates are considered a high-risk population for tuberculosis (TB) in Japan. However, they are currently only screened for active TB using chest X-ray (CXR) as part of an annual health check.OBJECTIVE: To evaluate the cost-effectiveness of screening for latent TB infection (LTBI) using interferon-gamma release assay (IGRA) on entry into prison institutions.METHOD: We developed a transmission model of TB, taking into consideration the TB and LTBI epidemiology among inmates in Japan. Using a decision tree, we compared and evaluated no screening, screening using CXR, and IGRA screening for LTBI with CXR upon entry for a hypothetical cohort of 10 000 persons, aged ≥20 years; active TB cases prevented was the health outcome.RESULTS: It was estimated that 314 active TB cases would occur in the absence of any screening policy. IGRA with CXR screening averted 176 cases, while just one case of active TB was averted with CXR only screening. The incremental cost-effectiveness ratio per active TB case prevented was respectively US$2672 and US$43 984 for IGRA + CXR screening and CXR only screening.CONCLUSION: Screening with IGRA should be considered as the most cost-effective screening policy for prison inmates.

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