Discrimination of Exudative Pleural Effusions Based on Pleural Adenosine Deaminase (ADA)-C-Reactive Protein (CRP) Levels, and Their Combination: An Observational Prospective Study

Abstract

(1) Background: Malignant (MPE), parapneumonic (PPE) and tuberculous (TPE) pleural effusions constitute common causes of pleurisy. Discriminating among them is usually challenging. C-reactive protein (CRP) and adenosine deaminase (ADA) pleural levels (p-CRP, p-ADA) have been used as differentiators in many studies showing promising results. This study aims to evaluate the diagnostic value of p-CRP, p-ADA levels and their combination among the three categories. (2) Methods: A prospective study of 100 patients with MPE (n = 59), PPE (n = 34) and TPE (n = 7) from a single centre was performed. p-CRP levels were evaluated between PPE and non-PPE and between complicated (CPPE) and non-complicated PPE. ADA levels were also measured to classify patients among MPE and non- MPE. Eventually, the combination of p-CRP and p-ADA values was used as a discrimination factor among PPE, MPE and TPE. (3) Results: ROC analysis revealed that p-CRP with a cut-off value: 4.4 mg/dL can successfully differentiate PPE (AUC = 0.998). The cut-off level of 10 mg/dL can predict CPPE with sensitivity: 63%, specificity: 71.4%, positive predictive value (PPV): 89%, and negative predictive value (NPV): 33%. Furthermore, patients with ADA levels ≤ 32 U/L were more likely to belong to the malignant group sensitivity: 93%, specificity: 78%, PPV: 85.9%, and NPV: 88.9%. Discriminant analysis showed that the combination of p-CRP and p-ADA levels can discriminate PPE, MPE and TPE in 93% of cases. (4) Conclusion: This study provides evidence that p-CRP and p-ADA levels could be possibly used in clinal practice in order to establish a diagnosis among MPE, PPE and TPE.

Clinical Value of Pleural Effusion and Serum MMP-3 and CYFRA21-1 Combined with ADA in Differential Diagnosis of Pleural Exudative Effusion

“…Pleural exudative e usion (PEE) is the most common one in pleural e usion, and it is mainly caused by benign lesions such as tuberculosis, in ammation, and connective tissue disease, as well as malignant tumors such as lung cancer, pleural mesothelioma and metastatic tumor. According to the di erent properties of PEE, it can be divided into benign PEE and malignant PEE [1,2]. At present, the identi cation of benign and malignant PEE is mainly through medical history, pleural e usion examination, pleural biopsy, and exfoliated cytology culture in the thoracic cavity [3][4][5].…”

Analysis of clinical characteristics and risk factors of community-acquired pneumonia complicated by parapneumonic pleural effusion in elderly patients

“…Poor clinical outcomes and increased mortality can be associated with the development of parapneumonic effusions [ 20 ]. Research shows that hypoalbuminaemia, hyponatraemia and an elevated CRP have been identified as independent risk factors for mortality [ 8 , 21 ]. In this study, a retrospective analysis of the clinical data of 132 elderly patients with CAP in our hospital showed that the proportion of elderly patients with CAP combined with PPE was 40.9%, and the in-hospital mortality of pneumonia patients with PPE was significantly higher than those of patients with pneumonia alone.…”