Abstract

Background: A routine laboratory test like complete blood count is a common practise during any hospital visit. It doesn’t provoke social stigma, especially when diagnosis of infectious diseases like tuberculosis and Human Immuno Deficiency Virus (HIV) infection are to be done. Thus if tested for its potential to diagnose or screen tuberculosis co-infection among people living with HIV, it will serve as a valuable laboratory evidence to start treatment in such vulnerable population. We hereby address the plausibility of using haematological parameters as screening tools to identify TB among People Living with HIV.

Methods: Our retrospective analysis included four cohorts of people, 259 healthy volunteers, 299 newly diagnosed tuberculosis patients, 135 PLHIV and 255 HIV-TB co-infected patients, wherein we tried to identify haematological variables with higher potential to distinguish among these groups.

Results: We report for the first time, a three analyte haematological signature (anemic-decreased CD4-increased Monocyte Lymphocyte Ratio (MLR)) which has higher capacity to serve as HIV-TB screening tool among PLHIV population (sensitivity 88.9%, specificity 91.7%, AUC-0.965). Another three analyte signature with increased MLR-neutrophilic- thrombocytotic nature has a sensitivity of 90.1%, specificity of 91.3% and AUC 0.957 in differentiating healthy people from pulmonary tuberculosis patients. Followed by this, lymphocyte percentage and MLR as single haematological markers have sensitivity, specificity, AUC of 90.2%, 83.6%, 0.92% and 88.3%, 88%, 0.931% respectively in differentiating healthy from pulmonary tuberculosis population.

Conclusion: Further studies supporting this three analyte panel as biosignature for easy and effective screening of HIV-TB among the vulnerable PLHIV cohort is warranted, which is the need of the hour to prevent mortality caused by this co-infection.

Keywords: Lymphocyte; Diagnosis; Complete blood count; Biomarkers