Sano Fumikazu, Fukao Toshimichi, Yagasaki Hideaki, Kanemura Hideaki, Inukai Takeshi, Kaga Yoshimi, Nakane Takaya
Department of Pediatrics, Faculty of Medicine, University of Yamanashi, 1110 Shimokato, Chuo, Yamanashi 409-3898, Japan.
Children (Basel). 2023 Apr 10;10(4):703. doi: 10.3390/children10040703.
Heterozygous variants in the gene are linked to well-known neurological phenotypes. There has been growing evidence for a separate phenotype associated with variants in residue Arg756-fever-induced paroxysmal weakness and encephalopathy (FIPWE) or relapsing encephalopathy with cerebellar ataxia (RECA). With only about 20 cases being reported, the clinical features associated with mutations at Arg756 have not been fully elucidated. We report a case of FIPWE with a p.Arg756Cys change in the gene and a comparison of the clinical features, including electrophysiological examination, with previous cases. The 3-year-old male patient had normal psychomotor development, presenting with recurrent symptoms of generalized hypotonia with loss of gait, mutism, and dystonic movements only during febrile illnesses since 19 months of age. At 2.7 years of age, a third neurological decompensation episode occurred, during which electroencephalography (EEG) did not reveal high voltage slow waves or epileptiform discharge. Nerve conduction studies (NCS) also did not show latency delay or amplitude reduction. exon sequencing showed a heterozygous p.Arg756Cys mutation. While the patient experienced repeated encephalopathy-like episodes, including severe hypotonia during febrile illness, EEG and NCS did not reveal any obvious abnormalities. These electrophysiological findings may represent an opportunity to suspect FIPWE and RECA.
该基因中的杂合变异与众所周知的神经表型相关。越来越多的证据表明，存在一种与残基Arg756变异相关的独立表型——发热诱导的阵发性无力和脑病（FIPWE）或伴有小脑共济失调的复发性脑病（RECA）。由于仅报告了约20例病例，与Arg756突变相关的临床特征尚未完全阐明。我们报告了1例基因发生p.Arg756Cys改变的FIPWE病例，并将其临床特征（包括电生理检查）与既往病例进行了比较。这名3岁男性患者精神运动发育正常，自19个月大起仅在发热性疾病期间出现反复的全身肌张力减退、步态丧失、缄默和张力障碍性运动症状。2.7岁时发生了第三次神经功能失代偿发作，在此期间脑电图（EEG）未显示高电压慢波或癫痫样放电。神经传导研究（NCS）也未显示潜伏期延长或波幅降低。外显子测序显示存在杂合性p.Arg756Cys突变。虽然该患者经历了反复的脑病样发作，包括发热性疾病期间的严重肌张力减退，但脑电图和神经传导研究未发现任何明显异常。这些电生理结果可能为怀疑FIPWE和RECA提供了线索。
