Department of General Pediatrics, Division of Inherited Metabolic Diseases, University Hospital Heidelberg, Heidelberg, Germany.
J Inherit Metab Dis. 2013 May;36(3):525-33. doi: 10.1007/s10545-012-9517-7. Epub 2012 Sep 13.
Metabolic treatment in glutaric aciduria type I (GA-I) including a low lysine diet with lysine-free, tryptophan-reduced amino acid supplements (AAS), carnitine supplementation and early start of emergency treatment during putatively threatening episodes of intermittent febrile illness dramatically improves the outcome and thus has been recommended by an international guideline group (Kölker et al, J Inherit Metab Dis 30:5-22, 2007). However, possible affection of linear growth, weight gain and biochemical follow-up monitoring has not been studied systematically.
Thirty-three patients (n = 29 asymptomatic, n = 4 dystonic) with GA-I who have been identified by newborn screening in Germany from 1999 to 2009 were followed prospectively during the first six years of life. Dietary treatment protocols, anthropometrical and biochemical parameters were longitudinally evaluated.
Mean daily intake as percentage of guideline recommendations was excellent for lysine (asymptomatic patients: 101 %; dystonic patients: 103 %), lysine-free, tryptophan-reduced AAS (108 %; 104 %), energy (106 %; 110 %), and carnitine (92 %; 102 %). Low lysine diet did not affect weight gain (mean SDS 0.05) but mildly impaired linear growth in asymptomatic patients (mean SDS -0.38), while dystonic patients showed significantly reduced weight gain (mean SDS -1.32) and a tendency towards linear growth retardation (mean SDS -1.03). Patients treated in accordance with recent recommendations did not show relevant abnormalities of routine biochemical follow-up parameters.
Low lysine diet promotes sufficient intake of essential nutrients and anthropometric development in asymptomatic children up to age 6 year, whereas individualized nutritional concepts are required for dystonic patients. Revised recommendations for biochemical monitoring might be required for asymptomatic patients.
I 型戊二酸血症（GA-I）的代谢治疗包括低赖氨酸饮食，配合无赖氨酸、色氨酸减少的氨基酸补充剂（AAS）、肉碱补充剂，以及在间歇性发热疾病的潜在威胁发作期间及早开始急救治疗，这显著改善了预后，因此被一个国际指南小组推荐（Kölker 等人，J Inherit Metab Dis 30:5-22, 2007）。然而，线性生长、体重增加和生化随访监测可能受到的影响尚未得到系统研究。
2009 年之前，德国通过新生儿筛查确诊了 33 例 GA-I 患者（无症状患者 29 例，肌张力障碍患者 4 例），我们对这些患者进行了前瞻性随访，随访时间为发病后 6 年。我们纵向评估了饮食治疗方案、人体测量学和生化参数。
赖氨酸（无症状患者：101%；肌张力障碍患者：103%）、无赖氨酸、色氨酸减少的 AAS（108%；104%）、能量（106%；110%）和肉碱（92%；102%）的日摄入量均达到指南推荐的平均水平。低赖氨酸饮食并未影响体重增加（平均 SDS 0.05），但轻度影响了无症状患者的线性生长（平均 SDS -0.38），而肌张力障碍患者的体重增加显著减少（平均 SDS -1.32），线性生长发育迟缓的趋势（平均 SDS -1.03）。根据最新建议进行治疗的患者未表现出常规生化随访参数的明显异常。
低赖氨酸饮食可促进无症状儿童在 6 岁前获得充足的必需营养物质摄入和人体发育，而肌张力障碍患者需要个体化的营养方案。对于无症状患者，可能需要修订生化监测建议。
