CRA65 A RARE PRESENTATION OF PLEURAL EFFUSION: DIAGNOSTIC INSIGHT FROM A BLACK-COLORED TAP

JY Chan, YH Lim, YW Cheah, NL Lai, SK Teoh,

Respiratory Unit, Internal Medicine Department, Hospital Ampang

Introduction
Pleural effusion is a common finding in respiratory medicine and is typically classified as transudative or exudative effusion, reflecting distinct underlying causes.  While pleural effusion is commonly straw-coloured or haemoserous, unusual colours like black, milky, or green may indicate more complex pathology. We present the case of a 76-year-old man with black pleural effusion, providing insight into its underlying aetiology. 

Case Report
A 76-year-old chronic smoker with a 30 pack-year history, presented with pleuritic chest pain, cough, and dyspnoea for two weeks, following two months of constitutional symptoms.  Examination revealed a cachexic man with reduced chest expansion, decreased air entry and dullness on percussion over the right lung. Chest X-ray (CXR) showed a massive right pleural effusion with tracheal deviation.

Ultrasound guided pleural tapping drained 400 mL of black-colour pleural fluid. Macroscopic examination found heavy blood staining, precluding further fluid analysis.  CT thorax showed bilateral pleural effusion with right complex effusion; right tracheal deviation with intraluminal lesion within trachea and bronchus intermedius, causing complete collapse of right middle and lower lobe.  Lung malignancy was suspected, but the patient declined further investigations and opted for palliative care.  Pleural fluid cytology later revealed atypical cells positive for BerEp4 and negative for calretinin and TTF-1, suggestive of metastatic adenocarcinoma.

Conclusion
Black pleural effusion, though rare, has been associated with malignancy, pancreatico-pleural fistula, fungal infections, and haemolysis due to intrapleural bleeding.  In this case the black pleural effusion was likely due to chronic accumulation of blood secondary to metastatic adenocarcinoma.  Clinicians should consider these differential diagnoses in patients with an unusual presentation of pleural effusion, particularly in high-risk populations like chronic smokers.