Empyema Superimposed on Pseudochylothorax: A Report of a Rare Case

Abstract

Background: Pseudochylothorax is an uncommon chronic pleural effusion characterized by elevated pleural cholesterol levels and typically associated with long-standing pleural inflammation, most commonly Rheumatoid Arthritis (RA) and tuberculosis. Although usually sterile, secondary infection may rarely complicate the condition, particularly in immunocompromised patients, posing diagnostic and therapeutic challenges.

Case: A 54-year-old man with seropositive RA presented with progressive dyspnea and bilateral pleural effusions. Right-sided thoracentesis showed purulent fluid with very high LDH and low glucose, consistent with empyema. Left-sided fluid was milky with high cholesterol (634 mg/dL) and low triglycerides (74 mg/dL), confirming pseudochylothorax. Ether testing supported the diagnosis. The patient received antibiotics and right-sided chest drainage, while the left effusion was managed conservatively, resulting in clinical improvement.

Conclusion: Empyema superimposed on pseudochylothorax is extremely rare. Chronic lipid rich effusions may predispose to secondary infection, particularly in immunosuppressed hosts. Comprehensive pleural fluid analysis from both sides in bilateral effusions is essential for accurate diagnosis and timely management.

Keywords: Pseudochylothorax; Empyema; Rheumatoid Arthritis; Pleural Effusion

Citation

Rezaeifar P, Naghavinia A. Empyema Superimposed on Pseudochylothorax: A Report of a Rare Case. WebLog J Pulmonol Respir Res. wjprm.2026. b2603. https://doi.org/10.5281/zenodo.18870482