What are the pulmonary manifestations of Mixed Connective Tissue Disease and how are they managed?
The most feared complication is PAH. Involvement of the lungs is common (75%) in MCTD, although most patients are asymptomatic. Management involves identifying the specific abnormalities and directing therapy appropriately. Active inflammation, such as pleuritis, may respond to nonsteroidal antiinflammatory drugs (NSAIDs) or corticosteroids. Other medications such as azathioprine, mycophenylate mofetil, or cyclophosphamide may be used to treat ILD. Up to 25% will develop severe pulmonary fibrosis. Aspiration secondary to esophageal disease may also contribute to pulmonary disease. PAH is a major cause of mortality and morbidity in patients with MCTD. It usually is due to bland intimal proliferation and medial hypertrophy of pulmonary arterioles. Patients with nailfold capillary abnormalities similar to those seen in scleroderma are most at risk.
Here is the table on the listing of the typical pulmonary manifestations of MCTD and their relative frequencies.
Pulmonary Manifestations of Mixed Connective Tissue Disease
|Chest pain and tightness||7%|
|Chest x-ray findings|
|Small pleural effusions||5%–10%|
|High-resolution computed tomography scan findings|
|Interstitial lung disease/nonspecific interstitial pneumonia||66%|
|Pulmonary function studies|
|Decreased carbon monoxide diffusion||66%|