Diagnostic Value of Leukocyte Count Abnormalities in Newly Diagnosed Tuberculosis Patients

Background: The diagnosis of tuberculosis (TB) is frequently challenging given that the clinical and radiographic features of TB are often nonspecific. Altered leukocyte count ratios could serve as new tools of diagnostic orientation of tuberculosis. The aim of this study was to assess the diagnostic value of the leukocyte count ratios for the diagnosis of TB. Methods: This was a cross-sectional study including cases of newly diagnosed TB patients from registers of the TB treatment center of the Douala General Hospital. Control subjects were healthy volunteers, age and sex matched, recruited at the blood bank. Sociodemographic, clinical data and peripheral blood parameters were collected. The diagnostic value of leukocyte counts was determined using receiver operating characteristics curve analysis. Results: In total, 204 TB patients and 204 control subjects were included in the study. The gender of the participants was equitably distributed in the 2 study groups (male 61.8%; female 38.2%). The median age of TB patients was 33 years while that of control patients was 32 years. The monocyte-lymphocyte count ratio (MLR) and neutrophil-lymphocyte count ratio (NLR) were significantly higher in the TB patients group compared to control group. A NLR >1.19 and MLR >0.29 were identified as cut-off values for discriminating TB patients. The areas under the curves (AUC) were 0.77 and 0.84 for the MLR and NLR respectively. Conclusion: A raised NLR > 1.19 and MLR > 0.29 are predictive of tuberculosis. The NLR has greater diagnostic ability as evidenced by its higher AUC. Further research is needed to confirm or refute our findings.