Early Diagnosis of Active Tuberculosis Using Ultra Low-dose Chest CT

Study Overview
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Brief Summary
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The aim of this study is to evaluate ultra low dose chest computed tomography (ULDCT) for early diagnosis of active tuberculosis in cohort of close contacts of active pulmonary tuberculosis for 1 year follow up

Detailed Description
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The early diagnosis of active tuberculosis in close contacts have not yet been established. To evaluate the early detection of active pulmonary tuberculosis using ULDCT, the investigators will establish the observational cohort of close contacts living in the same space with active pulmonary tuberculosis. Participants will visit our center at enrollment, after 3 months, and 12 months and will be received ULDCT, chest X-ray and Interferon-gamma assays at each visit. One chest radiologist will interpret findings of ULDCT and chest X-ray. Patients diagnosed with active tuberculosis will be excluded from the study and treated based on World Health Organization guidelines.

Official Title
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Early Diagnosis of Active Tuberculosis Using Ultra Low-dose Chest CT to Predict Progression to Active Tuberculosis Among Contacts

Conditions
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Tuberculosis, Pulmonary, Latent Tuberculosis

Intervention / Treatment
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* Radiation: Ultra low dose chest computed tomography (ULDCT)
* Radiation: Chest X-ray
* Diagnostic Test: Interferon-gamma Release Assay (IGRA)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Close contacts of active pulmonary tuberculosis Family members of active TB patient who has lived together for more than one month, or work colleagues of active TB patient who has been working in the same office for more than 8 months Participants who received explanation of the research plan, understands and writes agreement. Exclusion Criteria: Vulnerable subjects with mental retardation or severe mental illness Patients who could not receive chest CT Pregnancy Close contacts who diagnosed active pulmonary tuberculosis

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Screening
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Close contacts of active pulmonary tuberculosis patients<br>One arm study of conducting ULDCT, chest x-ray, and IGRA | Radiation: Ultra low dose chest computed tomography (ULDCT)<br>* Participants in the study will receive ULDCT at enrollment, after 3-month visit, and after 12-month visit.<br>Radiation: Chest X-ray<br>* Participants in the study will receive chest x-ray at enrollment, after 3-month visit, and after 12-month visit.<br>* Other names: Chest radiograph;Diagnostic Test: Interferon-gamma Release Assay (IGRA)<br>* Participants in the study will receive IGRA test at enrollment, after 3-month visit, and after 12-month visit. About 11mL of blood will be drawn from the participants for test of T-SPOT®.TB test and QuantiFERON test.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of active pulmonary tuberculosis | Active pulmonary tuberculosis defined by WHO guidelines for treatment of drug-susceptible tuberculosis and patient care (2017 update) | For a year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Prevalence of active pulmonary tuberculosis at enrollment | Active pulmonary tuberculosis defined by WHO guidelines for treatment of drug-susceptible tuberculosis and patient care (2017 update) | Baseline | 
| Prevalence of latent tuberculosis at enrollment | Latent tuberculosis defined by guidelines on the management of latent tuberculosis infection | Baseline | 
| Change of ultra low dose chest CT findings in latent tuberculosis patients | Serial comparison analysis of CT findings in latent tuberculosis patients who diagnosed latent tuberculosis based on IFN-gamma assay | Baseline, 3-month follow-up, and 12-month follow-up |