School of Medicine, University of Nottingham, Nottingham, UK.
Neonatal Unit, University Hospitals of Derby and Burton NHS Foundation Trust, Derby, UK.
BMJ Paediatr Open. 2023 Oct;7(1). doi: 10.1136/bmjpo-2023-002066.
Phenylketonuria (PKU) is the most common inherited disease of amino acid metabolism, characterised by elevated levels of phenylalanine (Phe). There is a lack of infant feeding guidance for those with PKU. From birth to 6 months of age, breast feeding is the optimal nutrition for an infant and continuing breast feeding for infants with PKU is recommended by European guidelines. However, human breast milk contains Phe in varying quantities, and therefore, the effects breast feeding might have on infants with PKU needs careful consideration.
To assess the effects of breast feeding (exclusive or partial) compared with low-Phe formula feeding in infants diagnosed with PKU, on blood Phe levels, growth and neurodevelopmental scores.
The Cochrane Inborn Errors of Metabolism Trials Register, MEDLINE and Embase were searched (date of latest search: 9 August 2022). Studies were included if they looked at the effects of breast feeding in infants diagnosed with PKU compared with formula feeding. Predetermined outcomes included blood Phe levels, growth in the first 2 years of life and neurodevelopmental scores.
Seven observational studies (282 participants) met the inclusion criteria. All studies compared continuation of breast feeding with low-Phe formula versus formula feeding only. While most studies concluded that there was no difference in mean serum Phe levels in their follow-up period, two reported that breastfed infants were more likely to have a normal mean Phe level. Two studies described no difference in mean weight gain after birth, while one found that breastfed infants were more likely to have higher mean weight gain. Two studies commented that breastfed infants achieved higher developmental scores in childhood as compared with formula fed infants.
Although there are no randomised trials, observational evidence suggests that continuation of breast feeding and supplementation with low-Phe formula is safe and may be beneficial for infants diagnosed with PKU.
苯丙酮尿症（PKU）是最常见的氨基酸代谢遗传疾病，其特征是苯丙氨酸（Phe）水平升高。PKU 患儿的婴儿喂养指导存在不足。对于婴儿来说，从出生到 6 个月，母乳喂养是最佳的营养来源，欧洲指南建议继续为 PKU 患儿进行母乳喂养。然而，人乳中 Phe 的含量存在差异，因此，母乳喂养对 PKU 患儿的影响需要仔细考虑。
评估与低苯丙氨酸配方奶喂养相比，PKU 患儿进行母乳喂养（纯母乳喂养或部分母乳喂养）对血 Phe 水平、生长和神经发育评分的影响。
检索了 Cochrane 先天性代谢错误试验登记处、MEDLINE 和 Embase（最新检索日期：2022 年 8 月 9 日）。如果研究比较了 PKU 患儿的母乳喂养与配方奶喂养对血 Phe 水平、婴儿 2 年内生长和神经发育评分的影响，则纳入研究。预先确定的结局包括血 Phe 水平、生命最初 2 年的生长和神经发育评分。
7 项观察性研究（282 名参与者）符合纳入标准。所有研究均比较了继续母乳喂养与低苯丙氨酸配方奶与仅配方奶喂养的差异。尽管大多数研究得出的结论是，在随访期间，两组患儿的平均血清 Phe 水平无差异，但有两项研究报告说，母乳喂养的婴儿更有可能保持正常的平均 Phe 水平。两项研究描述了出生后平均体重增加无差异，而一项研究发现母乳喂养的婴儿更有可能获得更高的平均体重增加。两项研究评论说，与配方奶喂养的婴儿相比，母乳喂养的婴儿在儿童时期的发育评分更高。
尽管没有随机试验，但观察性证据表明，继续母乳喂养并补充低苯丙氨酸配方奶是安全的，可能对 PKU 患儿有益。
