Peric, Stojan (35750481700)Stojan (35750481700)PericZlatar, Jelena (57826101100)Jelena (57826101100)ZlatarNikolic, Luka (57825768600)Luka (57825768600)NikolicIvanovic, Vukan (57211858030)Vukan (57211858030)IvanovicPesovic, Jovan (15725996300)Jovan (15725996300)PesovicPetrovic Djordjevic, Ivana (57815873500)Ivana (57815873500)Petrovic DjordjevicSreckovic, Svetlana (55979299300)Svetlana (55979299300)SreckovicSavic-Pavicevic, Dusanka (57212301497)Dusanka (57212301497)Savic-PavicevicMeola, Giovanni (7005543642)Giovanni (7005543642)MeolaRakocevic-Stojanovic, Vidosava (6603893359)Vidosava (6603893359)Rakocevic-Stojanovic2025-06-122025-06-122022https://doi.org/10.3389/fneur.2022.932883https://www.scopus.com/inward/record.uri?eid=2-s2.0-85135206566&doi=10.3389%2ffneur.2022.932883&partnerID=40&md5=fbbfedbe7ef75893ced228fb249da31fhttps://remedy.med.bg.ac.rs/handle/123456789/3360Introduction: Myotonic dystrophy type 2 (DM2) is a rare autosomal dominant multisystemic disease with highly variable clinical presentation. Several case reports and one cohort study suggested a significant association between DM2 and autoimmune diseases (AIDs). Aim: The aim of this study is to analyze the frequency and type of AIDs in patients with DM2 from the Serbian DM registry. Patients and Methods: A total of 131 patients with DM2 from 108 families were included, [62.6% women, mean age at DM2 onset 40.4 (with standard deviation 13) years, age at entering the registry 52 (12.8) years, and age at analysis 58.4 (12.8) years]. Data were obtained from Akhenaten, the Serbian registry for DM, and through the hospital electronic data system. Results: Upon entering the registry, 35 (26.7%) of the 131 patients with DM2 had AIDs including Hashimoto thyroiditis (18.1%), rheumatoid arthritis, diabetes mellitus type 1, systemic lupus, Sjogren's disease, localized scleroderma, psoriasis, celiac disease, Graves's disease, neuromyelitis optica, myasthenia gravis, and Guillain-Barre syndrome. At the time of data analysis, one additional patient developed new AIDs, so eventually, 36 (28.8%) of 125 DM2 survivors had AIDs. Antinuclear antibodies (ANAs) were found in 14 (10.7%) of 63 tested patients, including 12 without defined corresponding AID (all in low titers, 1:40 to 1:160). Antineutrophil cytoplasmic antibodies (ANCAs) were negative in all 50 tested cases. The percentage of women was significantly higher among patients with AIDs (82.9% vs. 55.2%, p <0.01). Conclusion: AIDs were present in as high as 30% of the patients with DM2. Thus, screening for AIDs in DM2 seems reasonable. Presence of AIDs and/or ANAs may lead to under-diagnosis of DM2. Copyright © 2022 Peric, Zlatar, Nikolic, Ivanovic, Pesovic, Petrovic Djordjevic, Sreckovic, Savic-Pavicevic, Meola and Rakocevic-Stojanovic.antineutrophil cytoplasmic antibodiesantinuclear antibodiesautoimmune diseasesHashimoto autoimmune thyroiditismyotonic dystrophy type 2 (DM2)