From Liver to Lung: A Pathological Journey of Bilothorax.

Bilothorax is a rare and pathological condition characterized by the accumulation of bile in the pleural cavity. This phenomenon most commonly occurs on the right side due to anatomical proximity to the liver and biliary system. Bilateral or left-sided bilothorax remains exceedingly rare. Diagnosis relies on pleural fluid analysis, particularly a pleural-to-serum bilirubin ratio >1, and imaging. We report the case of a male patient in his mid-60s with hepatitis C-related cirrhosis (Child-Pugh B7), hepatocellular carcinoma with pulmonary metastases, and multiple comorbidities, including diabetes mellitus and portal hypertension. The patient was undergoing systemic therapy with atezolizumab and bevacizumab, presented with chronic infected wounds and systemic symptoms and later developed gallbladder perforation with biliary peritonitis. Despite multidisciplinary management including percutaneous drainage, intravenous antibiotics, and intensive care support, his condition deteriorated. Subsequently, he developed a right-sided bilothorax, confirmed via thoracentesis, with a pleural-to-serum bilirubin ratio of 3.4 (normal < 0.6). Cultures isolated Enterobacter, and the patient was treated with targeted antibiotics and chest tube drainage. However, he experienced progressive hepatic decompensation, recurrent sepsis, and respiratory failure, ultimately leading to a transition to hospice care. This case is noteworthy due to the extreme rarity of bilothorax, the diagnostic complexity in distinguishing it from other pleural effusions, and the management challenges it poses in patients with advanced cirrhosis and malignancy.