Long-term dietary management of Propionic acidemia (PA) includes natural protein restriction, and supplementation with medical formula enriched with leucine (Leu) and free of valine (Val), isoleucine (Ileu), methionine (Met), and threonine (Thr). As PA medical formulas have high leucine content, concerns started to arise regarding potential long-term health risks of unbalanced leucine intake. PA patients have chronically low plasma levels of Ile and Val, which led to the paradoxical need to supplement with propiogenic single amino acids (AAs). Our report takes a retrospective look at the long-term dietary management of four patients and its reflection on their plasma amino acids. The patients' total protein intake was above the recommended dietary allowance (RDA) and had a high Leu/Val and Leu/Ile intake ratios in diet. Despite adequate total protein intake, patients had chronically low plasma Ile and Val and a high plasma Leu/Val and Leu/Ile ratios, which could be attributed to high Leu intake. We conclude that the best approach to PA dietary management is to only use medical formula with patients not meeting their RDA through natural protein, and to monitor plasma amino acids levels closely.

丙酸血症 (PA) 的长期饮食管理包括限制天然蛋白质，以及补充富含亮氨酸 (Leu) 且不含缬氨酸 (Val)、异亮氨酸 (Ileu)、蛋氨酸 (Met) 和苏氨酸 (Thr) 的医用配方奶粉。由于 PA 医疗配方亮氨酸含量较高，人们开始担心亮氨酸摄入不平衡的潜在长期健康风险。 PA 患者血浆 Ile 和 Val 水平长期较低，因此需要补充丙酸单一氨基酸 (AA)。我们的报告回顾了四名患者的长期饮食管理及其对血浆氨基酸的影响。患者的总蛋白质摄入量高于推荐膳食摄入量（RDA），并且饮食中 Leu/Val 和 Leu/Ile 摄入量比例较高。尽管总蛋白摄入量充足，但患者血浆 Ile 和 Val 长期偏低，血浆 Leu/Val 和 Leu/Ile 比值较高，这可能是由于 Leu 摄入量较高所致。我们的结论是，PA 饮食管理的最佳方法是仅对未通过天然蛋白质达到 RDA 的患者使用药物配方，并密切监测血浆氨基酸水平。