Diagnostic value of neutrophil-to-lymphocyte ratio, fibrinogen-to-albumin ratio and red blood cell distribution width in tuberculosis combined with bacterial infection

Objective: To investigate the clinical significance of neutrophil-to-lymphocyte ratio (NLR), fibrinogen-to-albumin ratio (FAR), and red blood cell distribution width (RDW) in pulmonary tuberculosis (PTB) combined with bacterial infection of the lung. Metheds: 74 patients with pulmonary tuberculosis combined with bacterial infection of the lung attending the Sixth People's Hospital of Nantong City from January 2021 to December 2024 were selected as the infected group, and 96 patients with simple pulmonary tuberculosis admitted during the same period were selected as non-infected group, and the levels of NLR, FAR, and RDW in peripheral blood of the patients of the two groups were collected for determination, and NLR, FAR and RDW levels of the patients of the two groups were compared.The receiver operating characteristic (ROC) curve was used to assess the performance of the above indicators for early diagnosis of PTB combined with bacterial infection. Results: The levels of NLR, FAR and RDW were significantly higher in the infected group compared with the non-infected group, and the differences were statistically significant ( P < 0.05).The levels of NLR were positively correlated with the levels of leukocytes, C-reactive protein and D-dimer.ROC curve analysis showed that the area under the curve (AUC) for the diagnosis of pulmonary tuberculosis combined with bacterial infection by blood NLR, FAR and RDW were 0.861, 0.818, 0.799; the AUC value after the combination of the three was 0.982. The validation results showed that the diagnostic sensitivity (98.6%) and specificity (89.58%) of NLR and FAR combined with RDW were higher than those of NLR, FAR and RDW alone. Conclusion: Combined detection of blood NLR, FAR and RDW levels has high clinical diagnostic value for diagnosing pulmonary tuberculosis combined with bacterial infection.