Can Complete Blood Count Parameters and Serum Electrolyte Levels Have a Predictive Role in Differential Diagnosis of Tuberculosis from Community-acquired Pneumonia in Children?

The complete blood count (CBC) parameters and the ratios regarding these parameters have been demonstrated to be useful diagnostic biomarkers for many infectious diseases. Herein, we aimed to evaluate and compare the usefulness of the predictive role of the CBC in the differential diagnosis of pulmonary tuberculosis (TB) from community-acquired pneumonia (CAP) in children. We also compared serum electrolyte levels between the 2 diseases. In this retrospective study, we analyzed the efficacy of CBC parameters and neutrophil-to-lymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR), plateletto-lymphocyte ratio (PLR), neutrophil-to-monocyte-plus-lymphocyte ratio (NMLR), and serum electrolyte levels in the differential diagnosis of pulmonary TB from CAP in children. We also classified patients with TB into 2 groups according to the microbiologic confirmation. We investigated whether there is any difference regarding these parameters in patients with positive microbiologic results. A total of 163 patients diagnosed with TB and CAP were included in this study. The WBC, neutrophil and monocyte counts, NLR, MLR, NMLR, mean platelet volume (MPV), and C-reactive protein (CRP) values were higher in CAP. There was statistical significance among serum sodium and phosphorus (P) levels between the 2 groups. Microbiologic confirmation was determined in 37 (35.5%) patients with the diagnosis of TB. The NLR, MLR, NMLR, CRP, and P values were significantly higher in patients with microbiologic confirmation. The results of the present study suggest that complete blood count parameters, NLR, MLR, NMLR, and CRP can be useful and cost-effective markers in differentiating pulmonary TB from CAP in the early stages of diagnosis.