Clinical Science Consultants # 2

1. In the Diel study "Evidence-based Comparison of Commercial Interferon-gamma Release Assays for Detecting Active Tuberculosis -- a Meta-Analysis," select the appropriate value for the TSpot cut-off used to be considered for a positive result?

10 spots

3 spots

> or equal to 6 spots

Less than or equal to 5 spots

In the Diel study “Evidence based comparison of commercial interferon-gamma release assays for detecting active tuberculosis -- a meta-analysis,” the TSpot cut-off used to be considered for a positive result is > or = 6 spots.

Explanation

In the Diel study “Evidence based comparison of commercial interferon-gamma release assays for detecting active tuberculosis -- a meta-analysis,” the TSpot cut-off used to be considered for a positive result is > or = 6 spots.

2. False-negative TST results can occur when children suffer from severe active TB or immune suppression.

True

False

In Long, “Interferon-Release Assay for the Diagnosis of Latent Mycobacterium tuberculosis Infection in Children Younger Than 5 Years: A Meta-Analysis,” False-negative TST results can occur when children suffer from severe active TB or immune suppression.

Explanation

In Long, “Interferon-Release Assay for the Diagnosis of Latent Mycobacterium tuberculosis Infection in Children Younger Than 5 Years: A Meta-Analysis,” False-negative TST results can occur when children suffer from severe active TB or immune suppression.

3. Of the available LTBI blood tests, which test demonstrated a better performance trend in BCG-vaccinated children?

TST

QFT

T-Spot

None of the above.

Although not statistically significant, QFT demonstrated a better performance trend in BCG-vaccinated children. Note, TST is not a blood test.

Explanation

Although not statistically significant, QFT demonstrated a better performance trend in BCG-vaccinated children. Note, TST is not a blood test.

4. It was suggested in the Diel study "Negative and Positive Predictive Value of a Whole-Blood Interferon-g Release Assay for Developing Active Tuberculosis'" that QFT is more reliable than the TST for identifying those who will soon progress to active TB, especially in children.

True

False

Results suggest that QFT is more reliable than the TST for identifying those who will soon progress to active TB, especially in children.

Explanation

Results suggest that QFT is more reliable than the TST for identifying those who will soon progress to active TB, especially in children.

5. Which diagnostic assay has the least amount of subjectivity in diagnosing latent TB infection?

QFT-TB Gold

TST

T-Spot

None of the above.

QuantiFERON-TB Gold has proven to have less subjectivity in diagnosing LTBI.

Explanation

QuantiFERON-TB Gold has proven to have less subjectivity in diagnosing LTBI.

6. In the Diel study mentioned above, there were only ___ of the 679 obtained papers met the inclusion criteria for this meta-analysis.

124 publications

412 publications

214 publications

142 publications

In the Deil study, there were only 124 of the 679 obtained papers met the inclusion criteria for this meta-analysis.

Explanation

In the Deil study, there were only 124 of the 679 obtained papers met the inclusion criteria for this meta-analysis.

7. In the Diel study "Negative and Positive Predictive Value of a Whole-Blood Interferon Gamma Release Assay for Developing Active Tuberculosis'", none of the contacts who tested QFT negative developed active TB.

True

False

In the Diel study, none of the contacts who tested QFT negative developed active TB.

Explanation

In the Diel study, none of the contacts who tested QFT negative developed active TB.

8. In Long, "Interferon-Release Assay for the Diagnosis of Latent Mycobacterium tuberculosis Infection in Children Younger Than 5 Years: A Meta-Analysis," showed that the sensitivity and specificity of ______ were slightly higher than ___ and can be used as supporting tools to detect LTBI in children younger than 5 years.

T-Spot and TST

TST and QFT-IT

IGRAs and TST

None of the above.

In Long, “Interferon-Release Assay for the Diagnosis of Latent Mycobacterium tuberculosis Infection in Children Younger Than 5 Years: A Meta-Analysis,” showed that the sensitivity and specificity of IGRAs were slightly higher than TST and can be used as supporting tools to detect LTBI in children younger than 5 years.

Explanation

In Long, “Interferon-Release Assay for the Diagnosis of Latent Mycobacterium tuberculosis Infection in Children Younger Than 5 Years: A Meta-Analysis,” showed that the sensitivity and specificity of IGRAs were slightly higher than TST and can be used as supporting tools to detect LTBI in children younger than 5 years.

9. In the Howley study, "Evaluation of QuantiFERON-TB Gold In-Tube and Tuberculin Skin Tests among Immigrant Children being Screened for Latent Tuberculosis Infection," which of the following was not one of the 3 countries in which the children were applying for immigration status from in this study.

Philippines

Africa

Vietnam

Mexico

In the Howley study, “Evaluation of QuantiFERON-TB Gold In-Tube and Tuberculin Skin Tests among Immigrant Children being Screened for Latent Tuberculosis Infection,” children from Mexico, Philippines and Vietnam were the 3 countries in which the children were applying for immigration status.
• Mexico
• Philippines
• Vietnam

Explanation

In the Howley study, “Evaluation of QuantiFERON-TB Gold In-Tube and Tuberculin Skin Tests among Immigrant Children being Screened for Latent Tuberculosis Infection,” children from Mexico, Philippines and Vietnam were the 3 countries in which the children were applying for immigration status.
• Mexico
• Philippines
• Vietnam

10. According to Diel, which statement is correct?

QFT has a higher sensitivity and higher specificity than T-Spot.

QFT has a higher sensitivity and lower specificity than T-Spot.

T-Spot has a higher sensitivity and higher specificity than QFT.

T-Spot has a higher sensitivity and lower specificity than QFT.

Explanation

T-Spot has a higher sensitivity and lower specificity than QFT.

11. More positives and fewer in-determinants results were noted by which assay in the Cheallaigh "Interferon Gamma Release Assays for the Diagnosis of Latent TB Infection in HIV Infected Individuals in a Low TB Burden Country" study?

QFT-TB

T-Spot.TB

QFT-IT

TST

In low TB prevalence settings, the QFT-IT yields more positive and fewer indeterminate results
than T-SPOT.TB. Negative results on the QFT-IT and indeterminate/unavailable results on the T-SPOT.TB were more common in individuals with low CD4+ T-cell counts.

Explanation

In low TB prevalence settings, the QFT-IT yields more positive and fewer indeterminate results
than T-SPOT.TB. Negative results on the QFT-IT and indeterminate/unavailable results on the T-SPOT.TB were more common in individuals with low CD4+ T-cell counts.

12. Cheallaigh, "Interferon Gamma Release Assays for the Diagnosis of Latent TB Infection inHIV-Infected Individuals in a Low TB Burden Country," states tuberculosis is the most common opportunistic infection in HIV-infected individuals and is responsible for how many of HIV associated deaths?

1/2

1/4

1/3

1/5

In the Cheallaigh study, “Interferon Gamma Release Assays for the Diagnosis of Latent TB Infection in
HIV-Infected Individuals in a Low TB Burden Country,” states tuberculosis is the most common opportunistic infection in HIV-infected individuals and is responsible for one-third of HIV associated deaths.

Explanation

In the Cheallaigh study, “Interferon Gamma Release Assays for the Diagnosis of Latent TB Infection in
HIV-Infected Individuals in a Low TB Burden Country,” states tuberculosis is the most common opportunistic infection in HIV-infected individuals and is responsible for one-third of HIV associated deaths.

13. The Negative Predictive Value (NPV) for the QFT in the Diel study was 98%.

True

False

The Negative Predictive Value (NPV) for the QFT in this Diel study was 100%.

Explanation

The Negative Predictive Value (NPV) for the QFT in this Diel study was 100%.

14. In Starke's article "Interferon-γ Release Assays for Diagnosis of Tuberculosis Infection and Disease in Children," about 50% infants who received a BCG-vaccine will respond with a significant induration to a TST.

True

False

The statement is true because in Starke's article, it is mentioned that approximately 50% of infants who received a BCG vaccine will have a significant induration (hardened bump) in response to a Tuberculin Skin Test (TST). This means that the BCG vaccine can cause a reaction that mimics a positive result for tuberculosis infection in the TST.

Explanation

The statement is true because in Starke's article, it is mentioned that approximately 50% of infants who received a BCG vaccine will have a significant induration (hardened bump) in response to a Tuberculin Skin Test (TST). This means that the BCG vaccine can cause a reaction that mimics a positive result for tuberculosis infection in the TST.

15. In the Garazzino study titled "Performance of interferon-γ Release Assay for the Diagnosis of Active or Latent Tuberculosis in Children in the First 2 Years of Age," in-determinants results were found to be related to age.

True

False

False.

Explanation

False.

16. Of the 2 U.S. commercially-available IGRAs, which one had a higher pooled sensitivity.

T-Spot

QuantiFERON-TB Gold

Of the 2 commercially-available IGRAs,T-Spot has a higher pooled sensitivity.

Explanation

Of the 2 commercially-available IGRAs,T-Spot has a higher pooled sensitivity.

17. IGRAs are the "Gold Standard" for active TB testing.

True

False

There is no "Gold Standard" assay for active TB testing. IGRAs test for latent TB not active.

Explanation

There is no "Gold Standard" assay for active TB testing. IGRAs test for latent TB not active.

18. In the Diel study "Negative and Positive Predictive Value of a Whole-Blood Interferon-g Release Assay for Developing Active Tuberculosis," how many of the TB contacts would the TST at >10mm cutoff were missed in the study that progressed to active TB?

10 out of 20

9 out of 19

8 out of 20

7 out of 19

In the Diel study, 9 out of 19 TB contacts who progressed to active TB with at TST cut-off of 10mm were missed.

Explanation

In the Diel study, 9 out of 19 TB contacts who progressed to active TB with at TST cut-off of 10mm were missed.

19. CDC recommends either TST or an IGRA for screening immigrant children age ___ from high risk countries.

2-14 years

< 5 years

>15 years

None of the above.

The CDC recommends either a Tuberculin Skin Test (TST) or an Interferon-Gamma Release Assay (IGRA) for screening immigrant children aged 2-14 years from high-risk countries. This age range is considered to be at higher risk for tuberculosis infection and therefore requires screening to ensure early detection and appropriate treatment if necessary.

Explanation

The CDC recommends either a Tuberculin Skin Test (TST) or an Interferon-Gamma Release Assay (IGRA) for screening immigrant children aged 2-14 years from high-risk countries. This age range is considered to be at higher risk for tuberculosis infection and therefore requires screening to ensure early detection and appropriate treatment if necessary.

20. In the Diel study "Evidence-based Comparison of Commercial Interferon-gamma Release Assays for Detecting Active Tuberculosis -- a Meta-Analysis," immuno-compromised patient had fewer in-determinates with T-SPOT.

True

False

In Diel, immuno-compromised patients, TSpot had fewer indeterminates.

Explanation

In Diel, immuno-compromised patients, TSpot had fewer indeterminates.