Accuracy of Seven Criteria Based on Cholesterol and Lactate Dehydrogenase for Differentiating Exudative and Transudative Pleural Effusions

Sep 30, 2026

Study evaluates diagnostic accuracy of pleural cholesterol and lactate dehydrogenase (LDH) thresholds and seven previously reported cholesterol-and-LDH classification criteria for distinguishing exudative from transudative pleural effusions. Patients were drawn from retrospective (BUFF) and prospective (SIMPLE) cohorts, with pleural biopsy, microbiological culture, and cytology confirming effusion causes. ROC analysis assessed individual marker performance and compared combined-threshold criteria with Light’s criteria. Pleural cholesterol and LDH were significantly higher in exudates, and combined thresholds showed accuracy comparable to Light’s criteria.

LanguageEnglish

CategoryHealthcare

FormatPDF

Pages6

Reading Time15 min

AccessFree to download

Background and Rationale

Study Design and Verification Methods

Diagnostic Evaluation with ROC Curves

Comparison with Light’s Criteria

Clinical and Biochemical Characteristics

[www. nature.com/scientificreports](www. nature.com/scientificreports) OPEN Accuracy of seven criteria based on cholesterol and lactate dehydrogenase for differentiating exudative and transudative pleural effusions Su-Na Cha1,2,3, Yan Niu4, Jian-Xun Wen4, Cheng Yan1,2,3, Li Yan3,5, Lei Zhang2,3, Mei-Ying Wang2,3, Wei Jiao2, Wen-Qi Zheng2,3, José M. Porcel6 & Zhi-De Hu1,2,3􀀍 Previous studies have proposed multiple diagnostic criteria based on cholesterol and lactate dehydrogenase (LDH) levels to differentiate pleural exudates from transudates. However, these criteria have not been widely validated, and no study has compared their diagnostic accuracies within the same population. This study recruited patients from retrospective (BUFF) and prospective (SIMPLE) cohorts. Pleural biopsy, microbiological culture, and effusion cytology were used to verify the causes of exudates or transudates. The diagnostic accuracy of pleural cholesterol and LDH levels in identifying exudates was evaluated using receiver operating characteristic (ROC) curves. Subsequently, the accuracies of seven previously reported cholesterol-and LDH-based classification criteria were compared with those of Light’s criteria. Pleural fluid cholesterol levels and LDH activity were significantly higher in exudates than in transudates. The area under the ROC curve (AUC) for pleural fluid cholesterol and LDH levels was 0.90 (95% CI: 0 .86–0.94) and 0.87 (95% CI: 0 .82–0.92) in combined cohort, respectively. We found that the diagnostic accuracy of the combination of pleural fluid cholesterol > 1.04 mmol/L (40 mg/dL) or pleural LDH > 0.6 upper limit of serum LDH reference interval was comparable to that of Light’s criteria, whereas the other criteria were less accurate. Combining pleural fluid cholesterol and LDH levels using the preceding thresholds has comparable accuracy to Light’s criteria for separating exudates from transudates. Keywords Pleural effusion, Cholesterol, Lactate dehydrogenase, Exudate, Transudate, Light’s criteria Pleural effusions can be classified as exudates or transudates, based on their pathophysiological mechanisms1. Exudative pleural effusions result from increased pleural membrane permeability due to inflammation, whereas transudative pleural effusions arise from elevated hydrostatic pressure or decreased oncotic pressure2,3. Common causes of exudates include malignancy, pneumonia, and tuberculosis, whereas congestive heart failure is the leading cause of transudates4,5. Accurate differentiation between exudates and transudates is the first step in theetiological diagnosis of pleural effusions6. Patients with transudative effusions typically do not require further diagnostic workup and can be managed with systemic therapy alone, whereas exudative effusions necessitate invasive procedures to establish the underlying cause3. Light’s criteria are the most widely used method for distinguishing exudates from transudates, with a sensitivity approaching 100% for identifying exudates, but with a specificity of approximately 70%7,8,9. Up to one-third of transudates may be misclassified as exudates, particularly in patients receiving diuretic therapy10–12. Therefore, improved methods for distinguishing between exudative and transudative pleural effusions are needed8, 13. 1Center for Clinical Epidemiology Research, the Affiliated Hospital of Inner Mongolia Medical University, Hohhot, China. 2Department of Laboratory Medicine, the Affiliated Hospital of Inner Mongolia Medical University, Hohhot, China. 3Key Laboratory for Biomarkers, Inner Mongolia Medical University, Hohhot 010010, China. 4Public Service Center for Medical Research, Inner Mongolia Medical University, Hohhot, China. 5Department of Respiratory and Critical Care Medicine, the Affiliated Hospital of Inner Mongolia Medical University, Hohhot, China. 6Pleural Medicine and Clinical Ultrasound Unit, Department of Internal Medicine, Arnau de Vilanova University Hospital, IRBLleid

FAQs

What is the purpose of this study on pleural effusions?

The study assesses how accurately pleural cholesterol and LDH levels, alone and combined, can differentiate exudative from transudative pleural effusions.

How were exudative vs transudative causes verified in the study?

Pleural biopsy, microbiological culture, and effusion cytology were used to verify the causes of exudates or transudates.

How did the combined cholesterol and LDH thresholds perform compared with Light’s criteria?

Using pleural cholesterol > 1.04 mmol/L or pleural LDH > 0.6 upper limit of the serum LDH reference interval produced diagnostic accuracy comparable to Light’s criteria, while the other seven criteria were less accurate.

Sep 30, 2026

Uploaded by Emma Wilson