The clinical significance of plasma sCD25 as valuable biomarker for progression and prognosis of tuberculosis

Background: sCD25 is an important immune molecule for T cell regulation. Tracking the detection of plasma sCD25 plays an important role in the evaluation of immune function, progression, and prognosis of tuberculosis (TB) patients. This study analyzed the association of plasma sCD25 levels with clinical, laboratory, CT imaging characteristics, and clinical outcome of TB patients. Methods: The clinical data of 303 TB patients treated in the Fifth People's Hospital of Suzhou from October 2019 to January 2022 were retrospectively analyzed. The levels of sCD25 in plasma were detected by ELISA. According to the cut-off threshold of plasma sCD25 levels, the patients were divided into below (Group TB1) and above (Group TB2) groups. The correlation of plasma sCD25 levels with clinical, laboratory, and CT imaging characteristics of TB patients, as well as their TB treatment outcome were analyzed. Results: The levels of plasma sCD25 of patients with TB patients were higher than that of the healthy control group ( P  < 0.01). Among the 303 TB patients, the levels were increased in Group TB2 patients (0.602 ± 0.216 vs. 1.717 ± 0.604 ng/ml, P  < 0.001), and there was a progressive reduction after anti-TB treatment. Furthermore, patients in Group TB2 showed higher positive rates in sputum smear (52.0% vs. 34.3%; P  = 0.003), sputum culture (69.7% vs. 56.9%; P  = 0.032), Xpert MTB/RIF (66.3% vs. 51.2%; P  = 0.013) and TB-DNA (51.5% vs. 31.2%; P  = 0.001) than those in Group TB1. Patients in Group TB2 had higher incidence in cough (78.8% vs. 62.3%; P  = 0.004), expectoration (64.4% vs. 45.1%; P  = 0.001), concomitant extrapulmonary TB (14.1% vs. 5.9%; P  = 0.016), cavities (47.9% vs. 34.0%; P  = 0.022), and unfavorable outcomes after anti-TB treatment. Conclusion: sCD25 plays an important role in the prognosis and clinical outcome of TB. Tracking plasma sCD25 detection of TB patients has evident clinical significance. It is noteworthy that when the plasma sCD25 levels are significantly elevated, patients should be cautious of the progression and unfavorable outcomes of TB.