苯丙酮尿症的新生儿筛查

目的 总结苯丙酮尿症新生儿筛查和治疗经验。方法 新生儿出生后72小时采足跟血，滴在规定的滤纸上，采用细菌抑制法或荧光法测定Phe浓度，Phe大于切割值(＞0.12mmol／L)，召回病人再次复查滤纸血Phe，仍高者，做确诊检查，确诊后以饮食治疗并随访。结果 1997～2000年对湖南省部分地区新生儿46323例筛查，确诊PKU患儿l例，结论 新生儿筛查是PKU患儿早期诊治的唯一方法。筛查出的PKU患儿经饮食治疗后体格智力发育可达正常，治疗越早效果越好。PKU患儿的母亲，再次妊娠必须通过产前诊断，选择正常儿出生。建立质量保征体系是对PKU筛查结果的准确性的有效保障。对初筛查阳性者，应了解其出生史和疾病史，排除假阳性可能，以免造成家长过分精神紧张。     

石家庄地区74例苯丙酮尿症患儿饮食干预情况分析

目的通过对石家庄市74例低苯丙氨酸饮食治疗的苯丙酮尿症患儿,监测血苯丙氨酸,选用Geselt发育量表进行智能发育评估,总结分析饮食治疗干预效果。方法确诊的74例苯丙酮尿症患儿中59例给予低苯丙氨酸饮食治疗,其中48例经新生儿疾病筛查,治疗起始年龄在3个月内,11例未接受新生儿疾病筛查,出现症状而就诊,治疗起始年龄8个月至27月,15例因各种原因放弃治疗给予正常饮食。通过对74例患儿定期随访,监测血苯丙氨酸浓度、智能发育水平,进行调查结果总结分析。结果通过新生儿疾病筛查,治疗起始年龄〈3个月的PKU患儿,智能发育水平达到正常水平（98．62±3．61）,因未接受新生儿疾病筛查而延迟治疗的11例PKU患儿,智能发育水平治疗前后对比差异有统计学意义（P〈0．05）,放弃治疗给予普通饮食的15例PKU患儿,智能发育水平明显落后于两组干预治疗的患儿。结论开展新生儿疾病筛查是早期发现PKU的有效途径,通过低苯丙氨酸饮食干预治疗,可以明显改善预后,避免患儿智能低下的发生。达到降低出生缺陷的目的。     

经典型苯丙酮尿症的治疗分析

作者选用经济,易得的普通低本丙氨酸食物,经过合理调配对1例经典型苯丙酮尿症患者进行了饮食治疗,评价近一年来踊跃随访和定期监测的结果,认为治疗效果满意。本文采用的这种治疗方案与其他治疗方法相比,更适合于普通家庭的经济承受能力,具有一定的推广和应用价值。     

新疆苯丙酮尿症43例饮食治疗及康复治疗

目的探讨不同年龄苯丙酮尿症的饮食治疗及康复治疗的方法。方法对1998年4月～2009年12月确诊的43例PKU进行饮食治疗及康复训练,其中新筛患儿8例。漏筛患儿35例。经典型34例,BH4缺乏型1例。结果治疗期间用体格指数评价及Gesell发育量表测定智商。经新筛8例,早期发现并早期治疗后患儿身高、体质量和头围均在正常范围,智商为（91±12）分。漏筛患儿坚持治疗28例,其中10例治疗前Gesell发育量表测定智商平均（51±18）分,治疗12～18个月,智商平均（70±15）分,治疗前后智商比较差异显著（t=1.705 P〈0.05）。结论进行新生儿筛查,早期诊断,早期饮食治疗是关键,开始治疗的年龄越小,预后越好,智商也越高。正确的指导,家长的配合是保证疗效的重要措施。     

苯丙酮尿症与新生儿筛查

苯丙酮尿症 (ｐｈｅｎｙｌｋｅｔｏｎｕｒｉａ ,ＰＫＵ)是一种较常见的先天性氨基酸代谢病 ,属单基因常染色体隐性遗传病。患儿由于肝细胞中苯丙氨酸 (以下简称Ｐｈｅ)羟化酶缺乏而导致高浓度的苯丙氨酸代谢产物 ,对大脑造成不可逆的损伤 ,如不及时治疗 ,将造成不可挽回的严重后果。由于其遗传异质性所造成的个体差异 ,许多患儿临床表现不典型 ,常造成误诊、漏诊严重 ,使患儿失去治疗机会 ,本文就此症及新生儿筛查作简要概述。1 ＰＫＵ的临床表现患儿出生时大多正常 ,早期症状无特殊性 ,可有呕吐、皮肤湿疹、易激惹和活动过度等表现 ;3- 4月…     

苯丙酮尿症的临床研究（附120例临床分析）

苯丙酮尿症（ＰＫＵ）是最常见的先天性代谢病之一，从１９８４年１１月至１９９３年４月收治ＰＫＵ患儿１２０例，其中６１例用无苯丙氨酸（ＰＡ）奶粉和低ＰＡ奶粉加低ＰＡ饮食疗法为奶粉治疗组，５９例用单纯饮食疗法为非奶粉组，年龄分为０－１月、１－３月、３－６月、６－１岁，１－２岁、＞２岁。两组同时做智商和脑电图（ＥＥＧ），奶粉治疗组０－３组治疗者智商及ＥＥＧ均正常，３－６月智商在正常低限，＞６月者低于正常，但有少数坚持合理治疗者，智商有的达正常水平。说明对于ＰＫＵ患儿的早期诊断和早期治疗是十分必要的，两组疗效比较有显著差异（Ｐ＜０．０５），两组ＥＥＧ异常发生率分别为５２．４６％，６０．１％差异显著（ｔ＝３．１８７６６，Ｐ＜０．０１），对于６月以下患儿用特殊奶粉加低ＰＡ饮食大大低于单纯饮食疗法，强调用无或低ＰＡ奶粉治疗是防止智力低下，改善预后的重要手段。     

新疆44例苯丙酮尿症的筛查、诊断与治疗

目的 报道新疆地区苯丙酮尿症（PKU）的筛查、诊断和治疗结果，对该地PKU的研究现状进行客观分析和评价。方法 新生儿筛查使用时间分辩荧光法。PKU诊断参照国际标准方法进行。治疗采用低苯丙氨酸饮食疗法。结果 通过新生儿筛查和全疆范围的走访调查等，发现并确诊PKU患者44例，包括汉族34例、维吾尔族7例、回族2例、哈萨克族1例。年龄范围从出生3天至27岁不等。经过对不同年龄段PKU患者实施严格饮食治疗显示，年龄较小（≤2岁）的患儿各项身体发育指标及智力水平都达到和接近了同龄正常儿童的生长发育水平。部分年龄偏大患儿（2—4岁）虽错过了最佳治疗时机但经饮食治疗后，其生理指标随病情缓解的同时有明显改善。而年龄更大（≥4岁）的患者，症状改善较慢，智力恢复提高不明显。结论 新疆的PKU患者失查严重，误诊误治甚忧，需要社会各界共同努力，促进PKU筛查及康复事业的发展进步。     

新疆地区5例苯丙酮尿症的临床分析

苯丙酮尿症 (ｐｈｅｎｙｌｋｅｔｏｎｕｒｉａ ,ＰＫＵ)是引起儿童智能障碍的常见原因之一 ,表现为苯丙氨酸 (Ｐｈｅ)代谢异常 ,除少部分系四氢生物喋呤合成酶或二氢生物喋呤还原酶缺失外 ,绝大部分病例源于苯丙氨酸羟化酶 (ＰＡＨ)异常 ,使得过量的Ｐｈｅ及其中间代谢产物等在血和脑脊液中蓄积 ,抑制功能酶类的活性 ,导致继发性代谢紊乱等 ,严重者甚至危及生命。为大致了解新疆ＰＫＵ的患病情况 ,我们对近几年来在我院和新疆医科大学附属医院发现的ＰＫＵ患者进行了调查和随访 ,现将资料介绍如下。病例资料1 一般资料 :本文调查随访了 5例…     

山西省经典型苯丙酮尿症患者苯丙氨酸羟化酶基因突变研究

目的 探讨山西省经典型苯丙酮尿症(phenylketonuria,PKU)患者苯丙氨酸羟化酶(phenylalanine hydroxylase,PAH)基因第3、6、7、11和12外显子的突变特征.方法 通过测序及序列比对的方法对山西省59例经典型PKU患者和100名正常儿童PAH基因进行序列分析,以确定其突变位点、性质和突变频率.结果 通过序列分析,发现在患儿和正常儿童中均出现Q232Q(CAA→CAG)、V245V(GTG→GTA)和L385L(CTG→CTC)3种单核苷酸多态性位点(single nucleotide polymorphism,SNP),其中患儿cDNA 696位点的SNP发生率高达96.2%,正常儿童的SNP发生率为97.0%;患儿cDNA 735位点的SNP发生率为76.1%,正常儿童的SNP发生率为77.3%;患儿cDNA1155位点的SNP发生率仅为7.6%,正常儿童SNP发生率为8.3%.正常儿童的其它序列与GenBank中序列比较的无差异.在患儿的基因序列中还发现了16种共计72个突变基因,占全部PAH突变基因的61.0%.第3外显子发现3种突变R111X、H64＞TfsX9和S70 del,突变频率分别为5.1%、0.8%、0.8%;第6外显子仅发现1种突变EX6-96A＞G,突变频率达10.2%;第7外显子中R243Q的突变频率最高,占12.7%,其次是Ivs7+2T＞A,占5.1%,T278I占2.5%,G247V、R252Q、L255S、R261Q、E280K均占0.8%;第11外显子中,Y356 X占5.9%,V399V占5.1%;第12外显子中,R413P占5.9%,A434D占2.5%.在16种突变中,有9种错义突变、3种剪接位点突变、2种无义突变及2种缺失,其中,H64＞TfsX9为本次研究新发现.结论 明确了山西省经典型PKU患者PAH基因第3、6、7、11和12外显子的突变种类和分布等特征,EX6-96A＞G、R243Q可能属于山西人群中PAH基因突变的热点.     

河南地区苯丙酮尿症患者苯丙氨酸羟化酶基因突变研究

目的 了解河南地区苯丙酮尿症(phenylketonuria,PKU)患者苯丙氨酸羟化酶(phenylalanine hydroxylase,PAH)基因突变情况,以便为苯丙酮尿症产前诊断和遗传咨询提供理论依据.方法 应用PCR产物直接测序对47例PKU患者及其父母PAH基因第1～13外显子及其两侧内含子进行序列分析.结果 在94条染色体中共检测到了83个PAH基因突变位点,检出率为88.3%(83/94),共发现了25种突变,其中突变E79fX13、H271R和D415Y国内外未见报道,突变VS10-14C＞G为国内首次报道.河南地区PKU患者的PAH基因突变集中在第6、7和11外显子,常见的7种突变是p.R243Q(20.5%)、EX6-96A＞G(12.0%)、p.Y356X(9.6%)、VS4-1G＞A(9.6%)、p.R111X(8.4%)、p.V399V(8.4%)、p.R413P(7.2%).结论 河南地区PKU患者PAH基因突变与中国其他地区相似,通过PAH基因直接测序可对大部分的PKU家系进行产前诊断.

Abstract：

Objective To study the characteristics of the phenylalanine hydroxylase gene (PAH)mutations in patients with phenylketonuria (PKU) in Henan province, in order to provide basic information for genetic counseling and prenatal diagnosis. Methods Mutations of the PAH gene were detected in exons 1-13 with flanking introns of PAH gene by PCR and DNA sequencing in 47 families with PKU. Results A total of 25 different mutations were detected in 83 out of 94 PAH alleles (88. 3%). Among them,E79fX13, H271R and D415Y have not been reported previously. It was the first time that IVS10-14C＞Gmutation was reported in Chinese PKU population. The mutations p. R243Q, EX6-96A＞G, p. Y356X,IVS4-1G＞A, p. R111X, p. V399V and p. R413P, were the prevalent mutations with relative frequencies of 20. 5 %, 12.0%, 9.6%, 9. 6%, 8. 4%, 8. 4% and 7.2% respectively. Conclusion The mutations of the PAH gene in patients with classical phenylketonuria in Henan province were similar to that in other areas of China. Prenatal gene diagnosis for PKU by PAH gene sequencing is efficient for most PKU families.     

Physical development in patients with phenylketonuria on dietary treatment: a retrospective study

Objectives

To evaluate the growth and physical development in patients with phenylalanine hydroxylase deficiency who follow exclusively dietary treatment.

Methods

Anthropometric measurements of 160 patients with hyperphenylalaninemia who were followed at our center over a 25 year period were obtained. Only patients treated exclusively with a protein-restrictive diet supplemented with amino acid mixtures were included. Height, weight and body mass index were measured at birth, at diagnosis, at 6 and 12 months of age, and annually until 18 years of age in patients with phenylketonuria or until 9 years of age in patients with mild hyperphenylalaninemia and compared to official national reference values. The final height of PKU patients was also compared to their expected family height.

Results

The analysis of z scores suggested no significant differences in physical development between PKU patients and the healthy population during the study period. The final height of PKU patients revealed that they were 2 to 4 cm taller than expected when compared to the mean family height (p < 0.001). The mean weight and BMI at puberty suggested that many patients with severe PKU, but not other phenotypes, were overweight during this period.

Conclusion

Physical development can be optimal in PKU patients regardless of their phenotype and the severity of the diet. A tendency to excessive weight gain is seen in adolescence in the most severe phenotypes.     

A comprehensive study of phenylalanine hydroxylase gene mutations in the Iranian phenylketonuria patients

Phenylketonuria (PKU) is a metabolic disorder caused by mutations in the phenylalanine hydroxylase (PAH) gene. After thalassemia, PKU is considered as the most common autosomal recessive diseases in the Iranian population. Therefore, an efficient diagnostic strategy is required to identify disease-causing mutations in this population. Following our first report in 2003, here we presented a comprehensive study on the mutation spectrum of the PAH gene in the Iranian population. This study was performed on 280 unrelated chromosomes from 140 Iranian patients with classic PKU. All 13 exons as well as exon-intron boundaries of the PAH gene were analyzed by direct DNA sequencing. Thirty four different mutations were identified by a mutation detection rate of 100%. IVS10-11G > A, p.P281L, R261Q, p.F39del and IVS11+1G > C were the most prevalent mutations with frequencies of 26.07%, 19.3%, 12.86%, 6.07 and 3.93%, respectively. All other mutations represented a relative frequency less than 3.5%. The data from this study provided a comprehensive spectrum of the PAH gene mutations which can facilitate carrier detection and prenatal diagnosis of PKU disease in the Iranian population.     

Structure-based epitope and PEGylation sites mapping of phenylalanine ammonia-lyase for enzyme substitution treatment of phenylketonuria

Protein and peptide therapeutics are of growing importance as medical treatments but can frequently induce an immune response. This work describes the combination of complementary approaches to map the potential immunogenic regions of the yeast Rhodosporidium toruloides phenylalanine ammonia-lyase (PAL, EC 4.3.1.5) and to engineer the protein as a human therapeutic agent for the treatment of phenylketonuria (PKU), an inherited metabolic disorder. The identification of B and T cell epitopes on the PAL protein was performed by computational predictions based on the antigenicity and hydrophilicity of proteins, as well as by experimental epitope mapping using a PepSpots peptide array (Jerini AG). Human T cell epitope mapping was performed by applying the computational EpiMatrix algorithm (EpiVax, Inc.) for MHC Class I and Class II associated T cell epitopes on PAL, which predicts which sequences are associated with binding to several different HLA alleles, a requirement for antigen presentation and subsequent primary immune response. By chemical modification through PEGylation of surface lysine residues, it is possible to cover the immunogenic regions of a protein. To evaluate this strategy, we used mass spectrometry to determine which of the immunogenic epitopes are covered by the covalent PEGylation modification strategy. This approach has allowed us to determine whether additional lysines are needed in specific residue locations, or whether certain lysine residues can be removed in order to accomplish complete molecular coverage of the therapeutic enzyme.     

A defective splice site at the phenylalanine hydroxylase gene in phenylketonuria and benign hyperphenylalaninemia among Palestinian Arabs.

Phenylketonuria (PKU) and benign hyperphenylalaninemia (HPA) result from different combinations of mutations at the locus for phenylalanine hydroxylase (PAH). While some of these mutations show widespread ethnic distribution, others are unique to specific communities. We report here the first point mutation common among Palestinian Arabs. The mutation (IVS2nt1) involves a dinucleotide substitution (Gg-->Aa) at the donor splice site of intron 2 of the PAH gene and abolishes a recognition site of the restriction enzyme MnlI. IVS2nt1 is associated with two PAH polymorphic haplotypes, 7 and 42. Homozygotes for this mutation are affected with severe, classical PKU. Compound heterozygotes carrying the IVS2nt1 allele and one of several other yet unknown mutations show different degrees of benign HPA.     

福建省新生儿苯丙酮尿症苯丙氨酸筛查切值的研究

目的探讨新生儿足跟血苯丙氨酸(Phe)测定在新生儿苯丙酮尿症筛查的切值(cut-off).方法新生儿出生72h后采足跟血,滴在规定的滤纸上.采用荧光测量法测定Phe浓度.结果通过一年半的新生儿足跟血筛查结果确定福建省新生儿苯丙酮尿症的筛查(Phe)切值为2.0mg/dL.结论新生儿足跟血Phe切值的确定为福建省今后开展大规模的新生儿苯丙酮尿症筛查提供依据:目前各实验室各自确定本实验室的Phe筛查切值,建议由国家卫生部组织进行苯丙酮尿症筛查Phe切值统一确定.     

高苯丙氨酸血症的抽搐机制研究

目的四氢生物喋呤缺乏症和苯丙酮尿症均可导致继发性癫痫,本研究拟探讨两类患者的临床与实验室特点。方法将两组患者出现癫痫的年龄、发作形式、脑电图特点及治疗预后进行比较。结果在391例晚治的高苯丙氨酸血症患者中,共有98例苯丙酮尿症和12例四氢生物喋呤缺乏症患者合并癫痫。98名苯丙酮尿症患者出现癫痫发作的年龄是10.7±4.6(4.5~27.1)个月,表现为多种形式,其中55例(56.1%)表现为婴儿痉挛症。经丙戊酸钠和其他抗癫痫药物治疗后,癫痫较难控制,经低苯丙氨酸饮食治疗后临床发作及脑电图均有所减轻。12例四氢生物喋呤缺乏症患儿出现癫痫的年龄为5.1±1.9(2.7~11.0)个月,主要表现为肢体铅管样扭转,哈气样症状。其中10例患者进行了脑电图检查,3例有轻度的痫样放电,7例脑电图正常。治疗后随访脑电图无特异性变化。在服用美多巴后,发作立即得到控制。结论四氢生物喋呤缺乏症和苯丙酮尿症导致癫痫的机制不同,两组患者发作开始年龄、形式、脑电图表现差异显著,治疗方法及预后完全不同。     

日照地区23例苯丙酮尿症患儿微量元素检测结果分析

目的全面了解日照市苯丙酮尿症（PKU）患儿给以低苯丙氨酸（Phe）饮食后,其末梢血铁、锌、钙、镁及铜的含量,探讨其缺乏的综合防治措施。方法对我市2003年6月-2010年6月筛查出的23例PKU患儿,取末梢血对铁、锌、钙、镁及铜进行检测。结果患病儿的末梢血中钙、锌的含量低于正常儿童（〈0.05）,而铁、镁、铜的含量无统计学意义（﹥0.05）结论患儿应全面搭配营养膳食,努力达到膳食结构的多样化,以保证患儿正常的生长发育。