Dirofilariasis as a cause of pleural effusion – A case report

This report highlights an exceptionally rare case of the dirofilariasis presenting with eosinophilic pleural effusion. A previously healthy 44-year-old male presented with a 1-month history of chest pain and cough. Chest computed tomography imaging revealed the right-sided pleural effusion, along with thickening of the parietal pleura. Thoracentesis was performed, yielding an eosinophilic effusion. Bronchoscopy was unremarkable, and microbiological cultures showed no significant findings. A uniporter video-assisted thoracoscopic surgery was conducted, during that a pathological lesion on the parietal pleura was identified and excised in its entirety. Histological analysis of the tissue confirmed an infection caused by the parasitic organism Dirofilaria spp. As complete surgical excision of the parasite is typically curative; no further treatment was necessary. The patient remained asymptomatic during the follow-up period. This case highlights the necessity of considering uncommon etiologist in the differential diagnosis of eosinophilic pleural effusion, especially in patients presenting with persistent or atypical clinical features.