PLEURAL FLUID LYMPHOCYTE NEUTROPHIL RATIO INTHE DIAGNOSIS OF TUBERCULOUS PLEURAL EFFUSION

Dr. P Aparna Devi; Dr. P Joyal Sandeep; Dr. N.Partha Sarathy; Dr. Kalapala Abhilash

Volume : VII, Issue : V, May - 2017

PLEURAL FLUID LYMPHOCYTE NEUTROPHIL RATIO INTHE DIAGNOSIS OF TUBERCULOUS PLEURAL EFFUSION

Dr. P Aparna Devi, Dr. P Joyal Sandeep, Dr. N. Partha Sarathy, Dr. Kalapala Abhilash

Abstract :

Background: Increased pleural fluid adenosine deaminase (ADA) activity is classically associated with tuberculous pleuritis. However, increasedactivity can also occur in a number of other diseases and this maynegatively affect the diagnostic utility of ADA measurements and decreaseits specificity for the diagnosis of tuberculosis (TB). The presence of ADAin pleural fluid reflects the cellular immune response in the pleural cavityand in particular, the activation of T lymphocytes. Different disease entitiesare typically associated with the presence of particular type of leucocytes. Objectives: To determine whether the combined use of ADA activity andlymphocyte neutrophil ratio would provide a more efficient means fordiagnosing tuberculous pleurisy than the use of ADA levels alone. Methods: Biochemistry, cytology and microbiology studies wereperformed on 90 consecutive pleural fluids. ADA and differential countswere determined on all exudative effusions. Results: ADA activity in tuberculous effusions was significantly higherthan in any other diagnostic group. At a level of 50U/L, the sensitivity,specificity, positive predictive value (ppv), negative predictive value (npv),and efficiency for the identification of TB calculated at 61%, 71%, 83%,45%, and 64% respectively. When the additional requirement of alymphocyte neutrophil ratio of 0.75 or greater was included, the sensitivity,specificity, ppv, npv and efficiency for the identification of TB werecalculated at 100%, 83%, 93%, 100% and 95%, respectively. Conclusion: ADA when combined with lymphocyte/neutrophil ratioremains a useful test in the diagnosis of tuberculous pleuritis.