Importance: Chronic graft-vs-host-disease (cGVHD) after allogeneic stem cell transplantation (AHSCT) may resemble autoimmune diseases. Anti-MDA5 (melanoma differentiation-associated gene 5) dermatopulmonary syndrome is a subset of dermatomyositis defined by specific clinical features and detection of anti-MDA5-antibodies in the serum.

Objective: To characterize the clinical features of patients who underwent AHSCT and screened positively for anti-MDA5 antibodies.

Design, setting, and participants: For this monocentric retrospective study, we exained 81 patients screened for anti-MDA5 antibodies at a specific dermatological or pulmonary postallograft consultation between January 2014 to September 2015 at a National Reference Center; 2 additional patients not seen at this consultation but having clinical features suggestive of anti-MDA5 syndrome were included. Twenty serum samples from patients after AHSCT without cGVHD were used as controls.

Main outcomes and measures: Anti-MDA5 antibodies screened using an immunodot assay.

Results: Of 83 patients who underwent AHSCT (mean [SD] age, 47 [14] years), 6 patients tested positive for anti-MDA5 antibodies (mean [SD] age, 43 [16] years) including 4 patients with interstitial lung disease and 3 patients with cutaneous clinical features similar to anti-MDA5 skin symptoms encountered in patients who have not undergone AHSCT, namely finger pad inflammation, palmar violaceous papules, and digital ulcerations. Three patients had severe respiratory symptoms resistant to systemic steroids, and 1 patient died of severe interstitial lung disease.

Conclusions and relevance: The clinical features and long-term prognosis of patients who underwent AHSCT and test positively for anti-MDA5 antibodies should be evaluated in large prospective studies.