<scp>IgG4</scp>‐Related Disease Associated With Myotonic Dystrophy Type 2

The prevalence of IgG4-RD in the cohort of DM2 herein is more than 1000 times higher than expected. As both diseases display common organ involvement, especially the pancreas, IgG4-RD screening should be considered in DM2 patients with diabetes or/and atypical associated phenotypes. Additionally, genetic testing for DM2 should be considered in IgG4-RD patients with elevated creatine kinase levels, myopathic phenotype, cardiac disorders and/or cataracts. The present report also suggests that IgG4-RD may have a genetic predisposition, potentially elucidating an aspect of the disease's pathophysiology.