In low prevalence countries, where identification and treatment of latent TB infection (LTBI) are basis of national programmes against tuberculosis, the diagnosis is focused mainly on tuberculin skin test (TST) and interferon gamma release assay (IGRA), both of which seem to be imperfect. This is why searches for a new, more specific biomarker for TB infection have been conducted. A promising candidate for the new marker is interferon gamma induced protein (IP-10). IP-10 is a chemokine, which can be detected in increased amounts in patients with active tuberculosis, latent TB infection and in individuals who had contact with an index case. It has been commonly suggested that a simultaneous analysis of IGRA and IP-10 level increases the effectiveness of IGRA, however it is still not certain whether measurement of IP-10 level might help distinguish between the above mentioned forms of tuberculous infection. Hopes are high as the protein is proved to be a good marker for treatment monitoring in adults, though there is no available data on its usefulness in monitoring therapy in paediatric population. More studies are still needed to fully assess the benefits of IP-10 level measurement as a biomarker for tuberculous infection, especially in children.