Spontaneous pneumomediastinum in anti-MDA5 dermatomyositis-ILD carries high mortality in small case series

ObjectiveSpontaneous pneumomediastinum (SPM) is a life-threatening complication of anti-melanoma differentiation-associated gene 5 antibody-positive dermatomyositis (MDA5 + DM) associated interstitial lung disease (ILD), particularly in patients with rapidly progressive ILD (RP-ILD), which carries an extremely high mortality rate. This study aimed to investigate the clinical characteristics, imaging features, and prognostic factors of MDA5 + DM-ILD patients with SPM to facilitate early detection and risk stratification of this high-risk population.MethodsThe study retrospectively analyzed the clinical data of nine patients diagnosed with MDA5 + DM-ILD complicated by SPM at the center between June 2022 and February 2025. Collected data included demographic characteristics, laboratory biomarkers [including serum ferritin and lactate dehydrogenase (LDH)], high-resolution computed tomography (HRCT) findings assessed through the validated MDA5-specific computed tomography (MDA5-CT) scoring system, treatment regimens, and clinical outcomes.ResultsThe cohort included 4 male and 5 female patients, with a median age of 62 years (range 42–69 years). All patients presented with RP-ILD and developed SPM during the disease course, with a median hospital stay of 10 days (range 4–31 days). The overall mortality rate was 87.5% (7/8, excluding 1 patient lost to follow-up). All non-survivors had high-risk MDA5-CT scores (>18 points), accompanied by significantly elevated serum ferritin [median 1936 ng/mL, interquartile range (IQR) 1,119–3,204 ng/mL] and LDH (median 433 U/L, IQR 327–646 U/L). The only surviving patient had a low-risk MDA5-CT score (≤18 points).ConclusionPatients with MDA5 + DM-ILD-SPM carry an extremely poor prognosis and high short-term mortality. An MDA5-CT score >18 is a strong predictor of mortality, particularly within the first 6 months after onset, with the highest risk in the first 3 months. Combining elevated serum ferritin, increased LDH, and tracheal dilation (>18 mm) may aid in early identification of high-risk patients for timely intervention.