101. Double-seropositive myasthenia gravis with acetylcholine receptor and low-density lipoprotein receptor-related protein 4 antibodies associated with invasive thymoma
- Author
-
Shunya Nakane, Osamu Higuchi, Yuichiro, Masaru Asahi, Hidehiro Ishikawa, Hidekazu Tomimoto, Akira Taniguchi, Atsushi Niwa, and Hidenori Matsuo
- Subjects
0301 basic medicine ,Thymoma ,03 medical and health sciences ,0302 clinical medicine ,Myasthenia Gravis ,Medicine ,Humans ,Receptors, Cholinergic ,Genetics (clinical) ,LDL-Receptor Related Proteins ,Acetylcholine receptor ,Aged ,Autoantibodies ,biology ,business.industry ,Autoantibody ,Middle Aged ,medicine.disease ,Myasthenia gravis ,Tacrolimus ,030104 developmental biology ,Neurology ,Pediatrics, Perinatology and Child Health ,LDL receptor ,Immunology ,biology.protein ,Female ,Neurology (clinical) ,Antibody ,business ,030217 neurology & neurosurgery ,Lipoprotein - Abstract
We describe two cases of myasthenia gravis (MG) with double seropositivity for acetylcholine receptor (AChR) and low-density lipoprotein receptor-related protein 4 (LRP4) antibodies (AChR/LRP4-MG) with invasive thymoma. Both cases showed myasthenic weakness, which was restricted to the ocular muscles for >5 months from onset, and then unprovoked severe clinical deterioration supervened with predominant bulbar symptoms. The patients responded adequately to therapeutic intervention. Serum AChR antibody levels at post-intervention were markedly decreased, whereas LRP4 antibodies were almost unchanged in case 1 and slightly decreased in case 2. Although our results suggest that patients with AChR/LRP4-MG are likely to present with more severe symptoms than those with LRP4-MG, none of the previously reported cases had thymomas. Coexistence of autoantibodies may reflect breakdown of self-tolerance caused by invasive thymomas. The main cause affecting symptoms of MG in our cases was probably AChR antibodies, and anti-LRP4 antibodies might have been an exacerbating factor.
- Published
- 2016