Characteristics and prognosis of interstitial pneumonias complicated with pneumomediastinum.

BACKGROUND:The clinical characteristics and prognostic impact of complication with pneumomediastinum in patients with interstitial pneumonias (IPs) are not well studied due to the relatively limited nature of available reports. The purpose of this study was to clarify the characteristics and prognostic factors of IPs complicated with pneumomediastinum. METHODS:Consecutive patients with IPs complicated with pneumomediastinum detected by computed tomography (CT) between July 1, 2011, and April 30, 2014 were retrospectively reviewed. Clinical data including symptoms associated with pneumomediastinum, laboratory data, lung function tests, treatments, and mortality were collected from medical records. RESULTS:Forty-five patients (25 males, 20 females), including 32 with idiopathic IP (IIPs) and 13 connective tissue disease-associated interstitial lung diseases (CTD-ILDs) were identified. The median age of onset of pneumomediastinum was 72 years (interquartile range [IQR] 68-79 years). The most common symptom associated with occurrence of pneumomediastinum was appearance or worsening of dyspnoea. No specific treatment was performed for most (84%) of the cases. The median period between occurrence and improvement of pneumomediastinum was 29 days (IQR 5-69 days). Multivariate analysis revealed that IIPs and no improvement of pneumomediastinum were associated with poor prognosis. CONCLUSIONS:Patients with IIPs complicated with pneumomediastinum and those without improvement of pneumomediastinum had poor prognosis.