Department of Laboratory Medicine, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
Department of Clinical Chemistry, Certe Groningen, Martini Hospital Groningen, Groningen, The Netherlands.
Pediatr Res. 2021 Nov;90(5):1058-1064. doi: 10.1038/s41390-021-01372-2. Epub 2021 Feb 11.
Vitamin B12 deficiency in children may be associated with (severe) neurological manifestations, therefore recognition is important. Diagnosing vitamin B12 deficiency in children is challenging. This study aimed to investigate plasma methylmalonic acid, holotranscobalamin, and total cobalamin in children 0-18 years of age and to estimate age-dependent reference intervals.
Plasma vitamin B12 markers were measured in collected plasma samples of 170 children 0-18 years visiting a local primary care laboratory. All had within-reference hemoglobin and MCV values. Pediatric plasma vitamin B12 biomarkers were measured and reference values were derived thereof.
Plasma methylmalonic acid was higher in young children, in particular between 1 and 6 months of age; total cobalamin and holotranscobalamin were highest from 0.5 to 4 years and decreased till 10 years of age. Plasma holotranscobalamin was highly correlated with plasma total cobalamin; their ratio was independent of age. Plasma methylmalonic acid was slightly more related to total cobalamin than to holotranscobalamin. A large proportion of mainly young children would be misclassified when adult references are applied.
Pediatric reference values for cobalamin markers are necessary to allow for early recognition and monitoring of children suspect of (clinical) cobalamin deficiency.
We analyzed three plasma vitamin B12 status markers, i.e., total cobalamin, holotranscobalamin, and methylmalonic acid, in the plasma of 170 children 0-18 years of age and were able to derive reference intervals thereof. Recognition of vitamin B12 deficiency in children is important but challenging as pediatric reference intervals for plasma vitamin B12 status markers, particularly plasma holotranscobalamin, are not well described. We think that our results may help early recognition and monitoring of children suspect of (clinical) vitamin B12 deficiency.
儿童维生素 B12 缺乏可能与（严重）神经表现有关，因此识别很重要。诊断儿童维生素 B12 缺乏具有挑战性。本研究旨在调查 0-18 岁儿童的血浆甲基丙二酸、全钴胺素和总钴胺素，并估计年龄相关的参考区间。
在当地初级保健实验室采集的 170 名 0-18 岁儿童的血浆样本中测量血浆维生素 B12 标志物。所有儿童的血红蛋白和 MCV 值均在参考范围内。测量儿科血浆维生素 B12 生物标志物并得出其参考值。
血浆甲基丙二酸在幼儿中较高，特别是在 1 至 6 个月龄之间；总钴胺素和全钴胺素在 0.5 至 4 岁时最高，然后下降至 10 岁。血浆全钴胺素与血浆总钴胺素高度相关；其比值与年龄无关。血浆甲基丙二酸与总钴胺素的相关性略高于与全钴胺素的相关性。当应用成人参考值时，主要是幼儿会被错误分类。
需要儿科钴胺素标志物参考值，以便及早识别和监测疑似（临床）钴胺素缺乏的儿童。
我们分析了 170 名 0-18 岁儿童血浆中的三种维生素 B12 状态标志物，即总钴胺素、全钴胺素和甲基丙二酸，并能够得出其参考区间。识别儿童维生素 B12 缺乏很重要，但具有挑战性，因为儿科血浆维生素 B12 状态标志物，特别是血浆全钴胺素的参考区间尚未得到很好的描述。我们认为我们的结果可能有助于早期识别和监测疑似（临床）维生素 B12 缺乏的儿童。
