IL4 and tuberculosis: This meta-analysis was based on 51 observational studies, of which 28 reported higher IL-4 levels in patients with TB,[9,11,21,22,24,28,32–37,39–42,44,46,48,49] 15 studies reported low levels of IL-4 in patients with TB,[12,25,26,30,38,43,45,47] and 8 studies did not report any variation in the control and patient groups.[14,23,27,29,31] First, an attempt was made to use a mixed healthy control group to separate latently infected and uninfected TB cases.