以阵发性运动障碍为表现的恶性苯丙酮尿症1例及文献综述

Malignant phenylketonuria presented with paroxysmal movement disorders:report of one case and review of the literature

目的苯丙酮尿症是由于肝中苯丙氨酸轻化酶或其辅酶四氢生物蝶呤缺陷引起的先天性代谢性疾病,属常染色体隐性遗传病。其中四氢生物蝶呤缺乏所致者又称恶性苯丙酮尿症,其临床表现变异较大,容易误诊。本文旨在引起对恶性苯丙酮尿症的重视,以减少临床误诊、误治。方法通过对1例以阵发性运动障碍为表现的恶性苯丙酮尿症患儿进行血苯丙氨酸测定、尿代谢筛查、苯丙氨酸和四氢生物蝶呤双负荷试验、尿液蝶呤分析,并结合文献复习进行综合分析。结果1岁6个月女孩的临床表现为阵发性运动障碍,血苯丙氨酸浓度正常,尿代谢筛查提示苯丙酮尿症,苯丙氨酸和四氢生物蝶呤双负荷试验、尿液蝶呤分析确诊为恶性苯丙酮尿症。结论恶性苯丙酮尿症在中国有很高的发病率和误诊率,临床上应引起高度重视。

Objective Phenylketonuria （PKU） is an autosomal recessive inborn error of phenylalanine （Phe） metabolism resulting from deficiency of phenylalanine hydroxylase （PAH）. Fewer phenylketonuria results from deficiency of tetrahydrobiopterin （BH4）, called malignant phenylketonuria, which was often misdiagnosed for its variant phenotype. Method A malignant phenylketonuria patient presented with paroxysmal movement disorders was studied via blood phenylalanine measurement, urine metabolism screening, phenylalanine and tetrahydrobiopterin stress test, and urine petrin analysis, A comprehensive analysis was made based on literature. Result A little one-year-and-six-month old girl presented with paroxysmal movement disorders;her blood phenylalanine concentration was normal; urine metabolism screen- ing suggested phcnylketonuria. She was diagnosed with malignant phenylketonuria according to phenylalanine and tetrahydrobiopterin stress test and urine petrin analysis. Conclusion There is a high incidence and misdiagnosis rate for malignant phenylketonuria in China, so more attention should be paid to it in clinic.