investigating causes of undiagnosed exudative pleural effusion by medical pleuroscopy and close biopsy

Introduction: pleural effusion may develop during various acute orchronic medical conditions. despite different diagnostic workups, somecases of pleural effusion may remain undiagnosed. pleuroscopy andclosed biopsy are common diagnostic approaches used for thediagnosis of undiagnosed cases. the present research aimed to evaluatethe diagnostic yield of medical pleuroscopy and closed biopsy in iran.materials and methods: the present cross-sectional study wasperformed within 2016-2018, in the north-east of iran. patients whohad undiagnosed lymphocytic predominance exudative pleural effusionwere included in the present research. every patient underwentmedical pleuroscopy or closed pleural biopsy by an abrams needle. thecollected data were analyzed in spss software (version 12).apvaluelessthan0.05was considered statistically signi7icant.results: a total of 108 patients with the mean age of 58.73±18.13 yearsenrolled in the present study. around 50 patients underwent needlebiopsy, while the other 58 patients went through medical pleuroscopy.chronic pleuritis, malignant pleural effusion, negative results, andtuberculosis were the common results. when pleuritis is regarded asnegative results and malignant and tuberculosis pleural effusion aspositive results, medical thoracoscopy provides more significantpositive results and fewer negative results (p=0.024). no patientdeveloped complications after the procedures.conclusion: in contrast to other studies, both of these techniques hadlow diagnostic yield for the diagnosis of undiagnosed pleural effusion.therefore, performing other diagnostic workups (e.g., imagingtechniques) may decrease the rate of undiagnosed pleural effusion.