Expression of lactoferrin in the peripheral blood of pulmonary tuberculosis patients and its clinical significance

Background: Pulmonary tuberculosis (PTB) affects patients' lives and reduces their quality of life. Lactoferrin (LF) is a member of the transferrin family. We explore the expression level of LF in the peripheral blood of PTB patients and the clinical significance of LF in the diagnosis and course evaluation of PTB. Methods: : Plasma LF concentration and neutrophil LF concentration were measured, and their correlation was analyzed, as well as their diagnostic validity and specificity for PTB. Results: : Plasma LF concentration of active PTB patients was higher than that of stable PTB patients and patients in the control group. Neutrophil LF concentration of active PTB patients was higher than that of the control group, whereas it was reversed in stable PTB patients. However, there was no significant difference in the levels of neutrophil LF and plasma LF between primary and retreated PTB patients. There was a positive correlation between them, and the LF level was positively correlated with the TB replication load. Neutrophil LF had a higher specificity and sensitivity for diagnosing stable PTB, while plasma LF had higher specificity and sensitivity in the diagnosis of active PTB. Conclusions: : Plasma LF has a higher sensitivity and specificity for the diagnosis of active PTB, and LF might be a biological indicator of PTB.