The challenge of tuberculosis (TB) remains in diagnosing the disease particularly in the young age group children. Clinical manifestations of TB in children are usually subtle and are not similar to the adult counterpart because of the... more
The challenge of tuberculosis (TB) remains in diagnosing the disease particularly in the young age group children. Clinical manifestations of TB in children are usually subtle and are not similar to the adult counterpart because of the pathogenesis of TB itself. The paucibacillary phase, which is common in children with TB and manifested as latent tuberculosis infection (LTBI), have several immunologic properties. The release of interferon (IFN)-g by blood mononuclear cells in LTBI have been observed and have been clinically applied as main principle for tuberculin skin test (TST). The test, however, is not specific for Mycobacterium tuberculosis since it was derived from the proteins of M. bovis. Antigen complex of early secretory antigen target (ESAT)-6 and culture filtrate protein (CFP)-10 are secretory protein expressed from gene locus of region of difference (RD)-1 specifically from M. tuberculosis and are interacting with circulatory T-cells which in turn would stimulate the release of IFN-g The laboratory test of enzyme-linked immunosorbent spot (ELISPOT) or TSPOT.TB and QuantiFERON®-TB (QTF) are using the principle of IFN-g release assay (IGRA) and are more specific and more sensitive than TST for diagnosing LTBI and active TB.
