Antititin antibody in early‐ and late‐onset myasthenia gravis. (20th June 2014)

• Record Type: Journal Article
• Authors: Szczudlik, P.; Szyluk, B.; Lipowska, M.; Ryniewicz, B.; Kubiszewska, J.; Dutkiewicz, M.; Gilhus, N. E.; Kostera‐Pruszczyk, A.
• Is Part Of: Acta neurologica Scandinavica. Volume 130:Number 4(2014:Oct.)
• Page Start: 229
• Page End: 233
• Publication Date: 2014-06-20
• Subjects: Neurology -- Periodicals; 616.8
• DOI: 10.1111/ane.12271
• Languages: English
• ISSNs: 0001-6314

Abstract

<abstract abstract-type="main" id="ane12271-abs-0001"> <title> <x xml:space="preserve">Abstract</x> </title> <sec id="ane12271-sec-0001" sec-type="section"> <title>Objectives</title> <p>Myasthenia gravis (MG) is an autoimmune disease caused by antibodies against neuromuscular junction proteins, 85% of patients have antibodies against acetylcholine receptor (AChR‐MG). Antititin antibodies are present in a subset of patients with MG. We aimed to determine the value of antititin antibodies as severity markers and thymoma predictors in early‐ and late‐onset MG.</p> </sec> <sec id="ane12271-sec-0002" sec-type="section"> <title>Materials & methods</title> <p>Two‐hundred and ninety‐five consecutive MG patients (188 F and 107 M) aged 12‐89 years (mean 50y) were included. 164 patients had early‐onset (EOMG, ≤50 years of age), 131 had late‐onset MG (LOMG). Twenty‐six patients had thymoma. symptoms, severity graded with MGFA scale, thymus histology, medications, and treatment results were analyzed.</p> </sec> <sec id="ane12271-sec-0003" sec-type="section"> <title>Results</title> <p>Antititin antibodies were present in 81 (27%) of all patients: 54% of thymoma MG, 0.6% of non‐thymomatous EOMG, and 55% of LOMG, with proportion of titin‐positive patients increasing linearly from 40% in the 6th to 88% in the 9th decade of life. Titin‐positive patients had more bulbar symptoms (<italic>P</italic> = 0.003). Severity of MG, need for immunosuppression, myasthenic crisis risk or treatment results were not related to its presence. Antititin antibodies had 56% sensitivity, 99% specificity, 90% positive predictive value (PPV), and 95% negative predictive value (NPV) for thymoma diagnosis in EOMG, and 50% sensitivity, 75% specificity, 71% PPV and 55% NPV in LOMG.</p> </sec> <sec id="ane12271-sec-0004" sec-type="section"> <title>Conclusions</title> <p>Antititin antibodies have high PPV and NPV for thymoma in EOMG. In MG without thymoma, antititin antibodies can be considered as markers of LOMG, but not of a severe course in our MG cohort.</p> </sec> </abstract>