Table 9_Transitioning of protein substitutes in patients with phenylketonuria: a pilot study.docx

IntroductionIn phenylketonuria (PKU), there is limited information about transitioning between protein substitutes and the influencing factors, particularly in young children. This pilot study assessed the stepwise transition from second to third-stage protein substitutes in children with PKU, aged 3–5 years.
MethodsDemographics, child behavior, maternal anxiety, and food neophobia scores were collected at baseline, mid-transition, and final assessment. Blood phenylalanine (Phe) was collected from 6 months pre-baseline to post-final assessment.
ResultsTwelve children (n = 4 males, 33%, median age 3.2 years) participated. Sixty-seven percent (n = 8) transitioned to liquid amino acid-based protein substitute and 33% (n = 4) to glycomacropeptide (cGMP) powder. Forty-two percent (n = 5/12) had a smooth transition (Group 1, median 3.5 months), while the remaining faced difficulty (n = 3, 25%, Group 2), or failed full transition (n = 4, 33%, Group 3). In Groups 2 and 3, caregivers failed to follow instructions, demonstrating inconsistencies and child resistance. Group 2 children had significantly higher blood Phe levels (above 360 μmol/L), that was significantly higher than Groups 1 and 3 (p < 0.01), with Groups 1 and 3 maintaining blood Phe within target (p < 0.01). Higher maternal education and nursery/school attendance significantly influenced transition success (p < 0.05). No significant differences were found in child neophobia, maternal anxiety, or child behavior (p > 0.05). Mothers generally reported satisfaction with the stepwise transition process.
ConclusionA stepwise transition to third-stage protein substitutes in PKU is effective, but is dependent on child metabolic control, parental education, and nursery/school support.

引言 苯丙酮尿症（phenylketonuria, PKU）患儿在蛋白质替代品之间过渡的相关信息较为有限，相关影响因素尤其在幼儿群体中尚未得到充分阐明。本先导性研究针对3~5岁的PKU患儿，评估了其从第二代至第三代蛋白质替代品的逐步过渡方案。
方法 分别于基线、过渡中期及最终评估阶段，收集人口统计学资料、儿童行为评分、母亲焦虑评分及食物新恐惧症（food neophobia）评分。血苯丙氨酸（phenylalanine, Phe）样本采集时段覆盖基线前6个月至最终评估后。
结果 本研究共纳入12名患儿（男性4名，占33%，中位年龄3.2岁）。其中67%（n=8）的患儿过渡至液态氨基酸基蛋白质替代品，33%（n=4）过渡至糖巨肽（glycomacropeptide, cGMP）粉剂。42%（n=5/12）的患儿过渡顺利（第1组，中位过渡时长3.5个月），剩余患儿分别出现过渡困难（n=3，占25%，第2组）或完全过渡失败（n=4，占33%，第3组）。在第2、3组中，照料者未严格遵循指导方案，存在操作不一致及患儿抗拒行为。第2组患儿的血Phe水平显著高于360μmol/L，显著高于第1组与第3组（p<0.01）；而第1、3组患儿的血Phe水平均维持在目标范围内（p<0.01）。较高的母亲受教育程度及患儿入托/入学情况对过渡成功具有显著正向影响（p<0.05）。儿童食物新恐惧症、母亲焦虑水平及儿童行为评分在各组间均无显著差异（p>0.05）。多数母亲对该逐步过渡方案表示满意。
结论 针对PKU患儿的第三代蛋白质替代品逐步过渡方案具备有效性，但该方案的实施效果依赖于患儿的代谢控制水平、父母受教育程度以及托育/学校支持。