IL4 and pulmonary tuberculosis: The results showed that there was no statistical difference between the serum IL-4 levels of individuals with extrapulmonary TB and healthy people (SMD = 0.166, [95% CI, −0.275 to 0.606], I2 = 75.7%, P = .461); 29 studies[9,11,12,14,21–27,29–32,34–39] report on the difference in serum IL-4 between pulmonary TB and healthy people.