TB Research

Distinctive Immuno-Inflammatory Pattern in Tuberculous Lymphadenitis: A Retrospective Cohort Study with Propensity Score Matching.

Muxing Chen, Fan Zhang, Zhixiong Yao, Yiping Liu, Di Wu, Xiaohong Chen, Youfei Lin

Infection and drug resistance · 2025-01

Abstract

PURPOSE: Tuberculous lymphadenitis (TBL) represents a common form of extrapulmonary tuberculosis (EPTB), yet its immunological characteristics compared to other EPTB forms remain poorly characterized. We aimed to compare immunological parameters between TBL and non-TBL patients to elucidate site-specific immune phenotypes.

PATIENTS AND METHODS: We conducted a retrospective single-center study at Fuzhou Pulmonary Hospital, China (April 2018-April 2024). From 1,408 EPTB patients screened, 862 met inclusion criteria after excluding immunocompromised patients, those with incomplete data, or age <18 years. Patients were stratified into TBL (n=337) and non-TBL EPTB (n=525) groups. To mitigate confounding, we implemented 1:1 propensity score matching based on demographic factors (age, sex) and nutritional status (BMI, hemoglobin, albumin), yielding 323 matched pairs. We compared inflammatory markers (neutrophil count, neutrophil-to-lymphocyte ratio [NLR]) and immunological parameters (lymphocyte count and T lymphocyte subsets: CD3+, CD4+, CD8+, CD45+) between groups using Mann-Whitney-tests and Spearman correlation analyses.

RESULTS: In matched cohorts, TBL patients demonstrated markedly higher lymphocyte counts than non-TBL patients (1.27 vs 1.04&#xd7;10/L,<0.001) despite comparable neutrophil counts (4.45 vs 4.49&#xd7;10/L,=0.724), resulting in significantly lower NLR (3.58 vs 4.38,=0.001). T lymphocyte subset analysis revealed substantially elevated absolute counts in TBL patients: CD3+ (1000.00 vs 829.00 cells/&#x3bc;L,<0.001), CD4+ (555.00 vs 474.00 cells/&#x3bc;L,=0.007), CD8+ (372.00 vs 305.00 cells/&#x3bc;L,<0.001), and CD45+ (1393.00 vs 1196.00 cells/&#x3bc;L,<0.001). Lymphocyte counts strongly positively correlated with all T cell subsets (CD3+:=0.72, CD4+:=0.72, CD8+:=0.55; all<0.001), while higher NLR values were associated with lower T cell subset counts.

CONCLUSION: TBL patients exhibit distinctive immunological characteristics, including lower NLR values and elevated T lymphocyte subset counts compared to other EPTB forms. These findings provide novel insights into site-specific immune responses to Mycobacterium tuberculosis infection, enhancing our understanding of the pathophysiological mechanisms underlying different manifestations of tuberculosis.