Performance of Commercial Blood Tests for the Diagnosis of Latent Tuberculosis Infection in Children and Adolescents

Abstract

Different blood tests for the diagnosis of latent tuberculosis infection in children seem to perform differently, because both QuantiFERON-TB tests were more likely than T-SPOT.TB to give indeterminate results in children <4 years of age.

Diagnosis of Mycobacterium tuberculosis

“…This combination of tests would improve the diagnosis of TB, and the child would be considered infected if either or both are positive (Debord et al, 2011;Pavic et al, 2011). Other studies with children older than five, HIV-infected children, or nonimmunosuppressed children, indicated that indeterminate results with QFT-G, QFT-IT, or T-SPOT.TB-were undetected or uncommon (Bergamini et al, 2009;Mandalakas et al, 2008;Tsiouris et al, 2006). …”

“…Differences in indeterminate results have been observed among the different INF-γ release assay tests given to children; with children, both QFT-G and QFT-IT (ELISA-based assays) are significantly more affected by indeterminate results than T-SPOT.TB (ELISPOT-based assay) (Bergamini et al, 2009). These indeterminate results can be minimized by applying the assays after acute inflammation is resolved; this later application also reduces the cost of retesting .…”

“…Some studies have shown that the QFT-IT has a high sensitivity and less indeterminate rates in nonimmunosuppressed children of all age groups (from 1 month to 18 years old) . However, others have shown that both forms of QuantiFERON-TB tests (QFT-G and QFT-IT) were less sensitive and can give more indeterminate results than T-SPOT.TB in children younger than 4 years old (Bergamini et al, 2009;Nicol et al, 2009;Takamatsu, 2008).…”

The Role of Interferon-gamma Release Assay in Tuberculosis Control

“…Weak cellular immune response is usually the reason why IGRA results are more often indeterminate in children than in adults (33). Some even prefer TST in diagnosing LTBI in smaller children over IGRA (27,34,35).…”

Indeterminate quantiferon TB Gold in Tube results from Turkey

“…(Table 1) There are few studies about the relationship between interferon gamma production and age. In a study of a large pediatric population, indeterminate results were found more frequent with QFT-IT than the other IGRA (T SPOT TB) especially in children < 4 years of age as 12.6% vs 2.3% (1). Although the indeterminate results were reported as follows 1.4%,17% (2,3).…”