The Impact Profile and Adenosine Deaminase of Age and Female Sex on Its Level in Patients with Pleural Effusion Syndrome

Abstract

Background: Pleural fluid analysis and closed pleural biopsy are integral parts in the investigative work up of an exudative pleural effusion. For diagnosis of tuberculous pleural effusion (TPE), the yield of pleural fluid culture for mycobacteria is low at about 36%. Objective: To evaluate the levels of adenosine deaminase (ADA) in the pleural fluids (P-ADA) of untreated and non-surgically manipulated female and male adult patients with several confirmed causes of PES. Methods: This was an observational study conducted at dept. of Internal Medicine, 250 Bedded Mohammad Ali Hospital, Bogura, Bangladesh from January to June 2023. 100 pleural fluid samples from 100 patients with proven causes of PES. The sample size was appropriate according to the study design. Written consent was obtained from all patients. It was precise enough to calculate descriptive and inferential statistics on type I and II errors, effect size, standard deviation, and was not influenced by administrative issues and costs. Results: 100 patients summarize the prevalence of the causes of PES and the demographic characteristics. TB was the most prevalent cause of PES (28/100, 28%). Most prevalent male sex was in the lymphoma group (4/0, 100%). None of the five patients with lymphoma were female. When the frequencies were compared for males and females, only adenocarcinoma and lymphoma were significant (chi- square tests, p=0.0021 and p=0.0003, respectively). The causes, prevalence, and median P-ADA (n/%/U/L) were tuberculosis (28/28.0/42.0), adenocarcinoma (24/24.0/9.75), transudate (21/21.0/6.85), simple parapneumonic pleural effusions (PPE; 10/10.0/9.38), complicated PPE/empyema (5/5.0/32.9), lymphoma (4/4.0/401.2), squamous cell carcinoma (4/4.0/13.11), and others (4/4/15.2). For P-ADA, Dunn's post hoc test revealed significance for tuberculosis vs. transudates, vs. simple PPE, and vs. adenocarcinoma (all P<0.05), and not significant for CPPE/empyema, lymphoma, SCC, and others (all P>0.05). For age, Dunn’s post hoc test revealed significance for tuberculosis vs. transudates, vs. simple PPE, and vs. adenocarcinomas (all P<0.05). Sex was not significant in the overall PES group (Chi=0.062, P=0.8028). Kendall's correlation of the relationship between P-ADA and age for pleural tuberculosis (n=26) was significant after 1000 iterations with bootstrap for 95% CI (Tau=-0.213, 95% CI - 0.449-0.0833, P=0.0490). A negative LOESS regression was evident between P-ADA and age >40 years. Conclusions: Evaluation of pleural ADA levels is useful for diagnosing pleural tuberculosis, while sex is not. A negative and significant relationship between P- ADA level and age >40 years was evident.