Tozawa Takenori, Nishimura Akira, Ueno Tamaki, Kaneda Daisuke, Miyanomae Yuri, Chiyonobu Tomohiro, Morimoto Masafumi, Hosoi Hajime
Department of Pediatrics, Ayabe City Hospital, Ayabe, Japan.
Department of Pediatrics, Kyoto Prefectural University of Medicine, Graduate School of Medical Science, Kyoto, Japan.
Neuropediatrics. 2018 Jun;49(3):200-203. doi: 10.1055/s-0037-1618591. Epub 2018 Jan 4.
Seronegative myasthenia gravis (MG) is a generalized form of MG that is diagnosed on the basis of clinical symptoms, electrophysiological testing, and pharmacological responses, in the absence of a seropositive status for anti-acetylcholine receptor (AChR) antibodies. Generalized MG that is seronegative for anti-AChR, anti-muscle-specific kinase (MuSK), and anti-low density lipoprotein receptor related protein 4 (Lrp4) antibodies is known as triple-seronegative MG. We here describe a case of triple-seronegative MG in an 8-year-old boy. His first symptom was dysphagia, at 3 years of age, and he subsequently developed ptosis, rhinolalia, and a waddling gait. A genetic analysis was conducted to exclude the possibility of congenital myasthenia syndrome due to the patient's resistance to steroid therapy. His condition was successfully managed with tacrolimus therapy over a 5-year follow-up period. Recently, several studies have reported the therapeutic utility of tacrolimus in juvenile seropositive MG; in contrast, a few reports have described tacrolimus treatment in cases of seronegative MG. Our findings suggest that tacrolimus therapy is a safe and effective option for the treatment of juvenile seronegative MG.
血清阴性重症肌无力（MG）是MG的一种全身性形式，在抗乙酰胆碱受体（AChR）抗体血清学阳性状态缺失的情况下，根据临床症状、电生理测试和药理学反应进行诊断。抗AChR、抗肌肉特异性激酶（MuSK）和抗低密度脂蛋白受体相关蛋白4（Lrp4）抗体均为血清阴性的全身性MG被称为三阴性MG。我们在此描述一例8岁男孩的三阴性MG病例。他的首发症状是吞咽困难，发生在3岁时，随后出现上睑下垂、鼻音和蹒跚步态。由于患者对类固醇治疗有抵抗性，因此进行了基因分析以排除先天性肌无力综合征的可能性。在5年的随访期内，他的病情通过他克莫司治疗得到了成功控制。最近，几项研究报道了他克莫司在青少年血清阳性MG中的治疗效用；相比之下，少数报告描述了他克莫司在血清阴性MG病例中的治疗情况。我们的研究结果表明，他克莫司治疗是治疗青少年血清阴性MG的一种安全有效的选择。
