On the other hand, two prospective studies conducted among HIV-negative patients, one from South Korea [25] and the other from the Philippines [26], found that unstimulated IP-10 performed well in differentiating between patients with active TB and LTBI, with sensitivity and specificity of 88% and 91% [25] and 95% and 93% [26], respectively. This evidence concerns the gene CXCL10 and tuberculosis.