Abstract:
ABSTRACT
Introduction: In countries with a high Tuberculosis(TB) burden, the differential diagnosis of TB
from pneumonia is difficult.
Objectives: To evaluate the role of NLCR in the differential diagnosis of pulmonary
Tuberculosis(PTB) and bacterial Community Acquired Pneumonia(CAP) at Ayder
comprehensive specialized hospital and Mekelle general hospital, Mekelle, Ethiopia.
Methods: A hospital based cross-sectional study was conducted from February to May, 2017. A
quota sampling technique was employed. Complete blood cell counts was determined before
antibiotic treatment using a Sysmex XT-4000i Hematology Analyzer. Erythrocyte sedimentation
rate(ESR) was done using westergren method. The Ziehl- Neelsen technique and Gene X-pert
were used for testing PTB and sputum culture for bacterial CAP. Student’s t-test, Pearson’s chi
square test and Receiver operating characteristics (ROC) curve analysis were used. A P value
?0.05 was considered statistically significant.
Result: The NLCR and ESR were significantly higher among PTB patients than bacterial CAP
patients. But, total white blood cell(TWBC) count was not significantly different in these two
groups of patients. Using NLCR together with ESR at their respective cut-off values (?2.72 and
?39) was seen to have largest area under the curve(AUC) (AUC =0.69; 95% Confidence
Interval(CI): 0.62, 0.77)). But, based on test for equality of ROC curve areas, it was not
significantly higher than that of the NLCR (0.644; 95% CI: 0.555, 0.733) and ESR (0.67; 95%
CI: 0.582, 0.759) (P-value=0.29). However, TWBC was found to be not a parameter
indiscriminating PTB from bacterial CAP (P-value>0.05).
Conclusion and recommendation: When using ESR and NLCR together at a time with their
respective cut off values gives of 69% accuracy in differentiating PTB patients from bacterial
CAP patients. Therefore, the use of ESR and NLCR in routine laboratory examination in
differentiating PTB from bacterial CAP is advisable especially in resource limited settings
