From the Guidelines
Pleural effusion in patients with lymphangioleiomyomatosis (LAM) is typically unilateral, though bilateral effusions can occur in some cases. The majority of LAM patients who develop pleural complications present with unilateral chylous effusions, most commonly on the right side, as noted in the guidelines for the diagnosis and management of lymphangioleiomyomatosis 1. These effusions result from the disruption of lymphatic vessels by the abnormal smooth muscle-like LAM cells that proliferate in the lungs, leading to leakage of lymphatic fluid (chyle) into the pleural space. The management of these effusions typically involves thoracentesis for diagnosis and symptom relief, dietary modifications to reduce chyle production, and in persistent cases, pleurodesis or thoracic duct ligation may be necessary, as suggested by the official American Thoracic Society/Japanese Respiratory Society clinical practice guidelines 1. Additionally, sirolimus (rapamycin), which targets the mTOR pathway implicated in LAM pathogenesis, has shown effectiveness in reducing pleural effusions in some patients, as noted in the guidelines 1. Some key points to consider in the management of LAM patients with pleural effusions include:
- The use of sirolimus before invasive management for symptomatic chylous fluid accumulations, as recommended by the official American Thoracic Society/Japanese Respiratory Society clinical practice guidelines 1
- The importance of considering the size and clinical impact of the effusion, comorbid factors, and local expertise in the management of chylothorax in LAM patients, as noted in the European Respiratory Society guidelines 1
- The potential for chylous fluid accumulations to require several months to respond to mTOR inhibitors and to recur after treatment cessation, as noted in the official American Thoracic Society/Japanese Respiratory Society clinical practice guidelines 1.
From the Research
Pleural Effusion in LAM Patients
- Pleural effusion (PE) in Lymphangioleiomyomatosis (LAM) patients is usually unilateral, with 76% of cases being unilateral and right-sided 2.
- The characteristics of PE in LAM patients include exudative chylothorax, predominantly lymphocytic, and with proportionately higher levels of proteins than lactate dehydrogenase 2.
- Pleural abnormalities, including pleural thickening, effusion, and pneumothorax, are common in LAM patients and can occur unilaterally or bilaterally 3.
- Unilateral pleurodesis is performed in some cases, with 68 out of 133 patients undergoing unilateral pleurodesis 3.
- Bilateral pleurodesis is also performed, with 65 out of 133 patients undergoing bilateral pleurodesis 3.
- The management of pneumothoraces in LAM patients includes pleurodesis, which can be performed unilaterally or bilaterally, and lung transplantation is still an option for patients who have undergone pleurodesis 4, 5.