A 3½-year-old girl, presented with delayed motor development and increased tone in lower limbs along with tight tendoachilles, toe walking and bilateral clonus. There were normal antenatal and perinatal period, however, after birth there was twitching of her lower limbs. Examination showed lower limb spasticity.Brain and spinal MRI along with EEG were normal. Serum amino acids revealed hyperprolinemia type 1. Hereditary spastic paraplegia gene panel confirmed a homozygous pathogenic variant in ALS2 gene, confirming a diagnosis of infantile onset ascending hereditary spastic paraparesis. She was fitted with ankle-foot orthotics, uses a Kaye walker and is on baclofen and diazepam as she can experience spasticity and painful muscle cramps. She is being managed by a multidisciplinary team involving paediatrician, paediatric neurologist, physiotherapist, occupational therapist, speech and language therapist, dietitian and social worker. Infantile onset ascending hereditary spastic paraplegia represents a rare cause of early onset spasticity with a progressive prognosis.

To analyze the result and follow-up data of screening for newborn amino acid metabolic disorders in Zhejiang province. A total of 1 861 262 newborns were screened for amino acid metabolic disorders during January 2009 and December 2016 in Zhejiang province. The screening results and the follow-up data were analyzed retrospectively. One hundred and sixty four cases were diagnosed as amino acid metabolic disorders with a prevalence of 1:11 349, including 83 with hyperphenylalaninaemia (1:22 400), 29 with neonatal intrahepatic cholestasis caused by citrin deficiency (1:64 138), 16 with methionine S-adenosyltransferase deficiency (1:116 250), 9 with maple syrup urine disease (1:206 667), 8 with argininemia (1:232 500), 7 with citrullinemia type Ⅰ (1:265 700), 6 with hyperprolinemia type Ⅰ (1:310 000), and 2 with carbamylphosphate synthetase Ⅰ deficiency(1:930 000). In addition, ornithine transcarbamylase deficiency, cystathionine β-synthase deficiency, argininosucoinate aciduria and tyrosinemia type Ⅰ were detected in one patient for each, respectively. Two patients had developmental delay, 7 patients were dead, and 2 cases of maple syrup urine disease were lost to follow-up. Hyperphenylalaninaemia is the most common amino acid metabolic disease in newborns in Zhejiang province. Patients with amino acid metabolic disorders identified in newborn screening program can have chance for normal growth development by intervention. 了解浙江省新生儿氨基酸代谢疾病的患病及转归情况。 回顾性分析2009年1月至2016年12月1 861 262名新生儿串联质谱筛查结果，并对确诊氨基酸代谢疾病的患儿的相关基因突变和随访情况进行分析。 共确诊氨基酸代谢疾病164例（1：11 349），其中高苯丙氨酸血症83例（1：22 400），希特林蛋白缺乏致新生儿肝内胆汁淤积症29例（1：64 138），其他依次为甲硫氨酸腺苷转移酶缺乏症Ⅰ型16例（1：116 250），枫糖尿症9例（1：206 667），精氨酸血症8例（1：232 500），瓜氨酸血症Ⅰ型7例（1：265 700），高脯氨酸血症Ⅰ型6例（1：310 000），氨甲酰磷酸合成酶缺乏症Ⅰ型2例（1：930 000），鸟氨酸氨甲酰转移酶缺乏症、胱硫醚β-合酶缺乏症、精氨酸代琥珀酸尿症、酪氨酸血症Ⅰ型各1例。随访发现，发育落后2例，死亡7例，失访2例，其他患儿均发育正常。 浙江省新生儿氨基酸代谢疾病以高苯丙氨酸血症最为常见，通过干预多数患儿发育良好。