Overall, in the study population, the median serum CRP level after 10–12 days of anti-TB treatment (CRP10–12d) decreased to 6.4 mg/L (IQR: 1.4–34.2 mg/L, W = 142, p = 0.001), thereby meeting the reference range of <8 mg/L established by the clinical laboratory of Centre of Tuberculosis and Lung Diseases at Riga East University Hospital. This evidence concerns the gene CRP and tuberculosis.