Anti-melanoma differentiation-associated gene-5 antibody-positive dermatomyositis with liver dysfunction: a warning sign of higher death risk

This study aimed to investigate and analyze the clinical and immunological features of patients with anti-melanoma differentiation-associated gene-5 antibody-positive dermatomyositis (MDA5 ⁺ DM) complicated with clinical liver dysfunction. A cohort of 85 patients diagnosed with MDA5 ⁺ DM admitted into Peking University People’s Hospital from 2006 to 2023 were retrospectively enrolled in this study. Clinical characteristics and survival status were collected and analyzed. Clinical liver dysfunction occurred in 28% (24/85) of MDA5 ⁺ DM patients. Patients with clinical liver dysfunction were more likely to have muscle impairment (83.3% vs. 52.5%, P = 0.009) and rapidly progressive ILD (72.7% vs. 47.4%, P = 0.027). Lactate dehydrogenase (LDH) (378.5 (296.0,453.8) U/L vs. 280.0 (218.0,355.0) U/L, P = 0.002) and ferritin (FER) (883.0 (279.8,2100.5) ng/mL vs. 293.5.0 (84.0,862.7) ng/mL, P = 0.040) were significantly elevated and total numbers of lymphocytes (827.2 ± 517.2 /μL vs. 1301.8 ± 720.9 /μL, P = 0.042), and CD4 ⁺ T cells (403.8 ± 315.9 /μL vs. 548.6 ± 257.7 /μL, P = 0.045) were significantly decreased in patients with clinical liver function. Muscle weakness (OR 5.184, 95% CI 1.305, 20.595, P = 0.019) was identified as an independent risk factor for clinical liver dysfunction. Clinical liver dysfunction was identified as an independent risk factor for poor prognosis in patients with MDA5 ⁺ DM (HR = 4.030, 95% Cl 1.233, 13.176, P = 0.021), with an 18-month survival rate of 69%. Liver dysfunction is one of the extramuscular manifestations in patients with MDA5 ⁺ DM and might be associated with a poor prognosis.