苯丙酮尿症患儿智力低下的影响因素及血清必需氨基酸和S-100β的检测价值

Influencing factors of mental retardation in children with phenylketonuria and the detection values of serum essential amino acids and S-100β

目的 探究苯丙酮尿症(PKU)患儿发生智力低下(MR)的影响因素,并分析血清必需氨基酸、中枢神经特异蛋白(S-100β)的检测价值。方法 选取2018年1月至2022年1月唐山市妇幼保健院收治的120例PKU患儿,均行对症治疗,治疗32周后采用0~6岁儿童神经心理发育量表(DST)评估患儿智力,统计MR(DST评分<70分)的发生情况,比较发生MR(n=32)与未发生MR(n=88)患儿的一般资料及治疗前后血清必需氨基酸、S-100β水平,分析PKU患儿发生MR的影响因素,分析治疗后血清必需氨基酸、S-100β水平及其治疗前后波动值与DST评分的相关性。结果 120例PKU患儿治疗32周后DST评分为(86.25±12.47)分,MR发生率为26.67%(32/120)。发生MR患儿的起始治疗年龄≥3个月占比(53.13%)、治疗方法为低苯丙氨酸饮食占比(87.50%)、监护人文化水平初中及以下占比(37.50%)、监护人遵医行为差占比(37.50%)均高于未发生MR患儿(29.55%、59.09%、18.18%、12.50%)(χ^(2)/U值分别为5.675、8.523、2.491、3.471,P<0.05)。治疗后,发生MR患儿的血清苯丙氨酸、S-100β水平均高于未发生MR患儿,差异均有统计学意义(t值分别为4.743、7.555,P<0.05);治疗前后波动值,发生MR患儿的血清苯丙氨酸、S-100β水平均低于未发生MR患儿,差异均有统计学意义(t值分别为4.760、2.800,P<0.05);发生MR患儿中,治疗后的血清赖氨酸、色氨酸、蛋氨酸、苏氨酸、异亮氨酸、亮氨酸、缬氨酸、组氨酸水平均高于治疗前,血清苯丙氨酸、S-100β水平均低于治疗前,经比较差异均有统计学意义(t值分别为12.659、3.144、3.598、5.331、4.691、3.218、3.562、7.381、4.231、11.179,P<0.05);未发生MR患儿中,治疗后的血清赖氨酸、色氨酸、蛋氨酸、苏氨酸、异亮氨酸、亮氨酸、缬氨酸、组氨酸水平均高于治疗前,血清苯丙氨酸、S-100β水平均低于治疗前,经比较差异均有统计学意义(t值分别为22.116、5.051、5.362、8.737、7.990、5.437、6.278、12.789、6.390、27.664,P<0.05)。起始治疗年龄、治疗方法、监护人文化水平、监护人遵医行为,以及治疗前后血清苯丙氨酸、S-100β水平波动值均为PKU患儿发生MR的影响因素(Waldχ^(2)值分别为26.882、7.002、9.956、10.108、12.063、9.759,P<0.05)。治疗前后血清苯丙氨酸、S-100β水平波动值与DST评分均呈正相关(r分别为0.528、0.459,P<0.05)。结论 PKU患儿MR的发生与起始治疗年龄、治疗方法、监护人文化水平、监护人遵医行为及治疗前后血清苯丙氨酸和S-100β水平波动值有关,检测治疗期间血清苯丙氨酸、S-100β水平的变化可反映患儿智力改变情况。

Objective To investigate the influencing factors of mental retardation(MR) in children with phenylketonuria(PKU) and to analyze the detection values of serum essential amino acids and central nervous specific protein(S-100β).Methods A total of 120 PKU children admitted to Tangshan Maternal and Child Health Care Hospital from January 2018 to January 2022 were selected.All children received symptomatic treatment,and the children's intelligence was assessed by the Developmental Screening Test(DST) for children aged 0-6 years after 32 weeks of treatment.The occurrence of MR(DST score <70 points) was counted,and the general data,serum essential amino acids and S-100β levels before and after treatment of children with MR(n=32) and those without MR(n=88) were compared.The correlation between serum essential amino acid and S-100β levels after treatment,their fluctuation values before and after treatment and DST score were analyzed.Results The DST score of 120 children with PKU after 32 weeks of treatment was(86.25±12.47) points,and the incidence of MR was 26.67%(32/120).The percentage of children with MR who started treatment at the age of ≥3 months(53.13%),treatment with low-phenylalanine diet(87.50%),guardian's education level of junior high school or below(37.50%),and guardian's poor compliance behavior(37.50%) were higher than those without MR(29.55%,59.09%,18.18% and 12.50%,respectively)(χ^(2)/U=5.675,8.523,2.491 and 3.471,respectively,P<0.05).After treatment,serum phenylalanine and S-100β levels were higher in children with MR than those in children without MR,and the differences were statistically significant(t=4.743 and 7.555,respectively,P<0.05).The fluctuation values before and after treatment,serum phenylalanine and S-100β levels were lower in children with MR than those in children without MR,and the differences were statistically significant(t=4.760 and 2.800,respectively,P<0.05).Among children with MR,serum lysine,tryptophan,methionine,threonine,isoleucine,leucine,valine and histidine levels were higher after treatment than before treatment,and serum phe-nylalanine and S-100β levels were lower than before treatment,and the differences were statistically significant(t=12.659,3.144,3.598,5.331,4.691,3.218,3.562,7.381,4.231 and 11.179,respectively,P<0.05).Among children without MR,serum lysine,tryptophan,methionine,threonine,isoleucine,leucine,valine,and histidine levels were higher after treatment than before treatment,and serum phenylalanine and S-100β levels were lower than before treatment,and the differences were statistically significant(t=22.116,5.051,5.362,8.737,7.990,5.437,6.278,12.789,6.390 and 27.664,respectively,P<0.05).Age of starting treatment,treatment method,guardian's literacy level,guardian's compliance behavior,and fluctuating values of serum phenylalanine and S-100β levels before and after treatment were the influencing factors of the occurrence of MR in children with PKU(Wald χ^(2)=26.882,7.002,9.956,10.108,12.063 and 9.759,respectively,P<0.05).The fluctuation values of serum phenylalanine and S-100β levels before and after treatment were positively correlated with DST score(r=0.528 and 0.459,respectively,P<0.05).Conclusion The occurrence of MR in PKU children is related to the age of starting treatment,treatment method,guardian's literacy level,guardian's compliance behavior,and fluctuating values of serum phenylalanine and S-100β levels before and after treatment.The changes of serum phenylalanine and S-100β levels during treatment can reflect the changes of children's intelligence.