11th January 2024

A 59-year-old lady attends Rheumatology Clinic for her annual review of her rheumatoid arthritis management.

A 59-year-old lady attends Rheumatology Clinic for her annual review of her rheumatoid arthritis management. She is managing well from a joint pathology point of view and scores 3.5 on her DAS28. However, she reports worsening shortness of breath for the past few months. A chest x-ray is completed, which shows evidence of a unilateral pleural effusion. An ultrasound-guided diagnostic aspiration of the fluid reveals a white-coloured liquid. 

Investigations: 

Pleural fluid triglycerides: 14mg/dL 

Pleural fluid cholesterol crystals – present. 

Given the above pleural fluid characteristics, what is the most likely cause of this patient’s pleural effusion?

Select the SINGLE most appropriate option from the list below. Select ONE option only.