Rikke Møller, Ebba Nexo, George PrayGod, Belinda Kweka, Happyness Kunzi, Maimuna Ahmed, Suzanne Filteau, Melissa Gladstone, André Briend, Henrik Friis, Mette Frahm Olsen
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引用次数: 0
Abstract
Background: B12 deficiency is related to impaired neurodevelopment and anaemia and is a global health concern in children with severe acute malnutrition (SAM).
Objective: We investigated B12 status in children with SAM and among non-malnourished comparisons and assessed the validity of the plasma B12 assay.
Methods: This study was part of a pilot study of a nutritional intervention. We measured plasma levels of B12, methylmalonic acid (MMA), total haptocorrin (HC) and total transcobalamin (TC), in children with SAM before and after eight weeks of nutritional treatment and at a single timepoint in non-malnourished children.
Results: We included 82 children with SAM and 82 children without acute malnutrition. Plasma B12 was higher in SAM at enrolment than in controls (median 647 vs 411 pmol/L) and declined after treatment (median 469 pmol/L). Baseline plasma B12 was particularly high in children with oedematous SAM compared to those without oedema (p=0.050). In contrast, plasma MMA was higher in those with SAM, reflecting lower B12 function (median 220 vs 170 nmol/L), and declined after treatment (median 190 nmol). HC was positively correlated to B12 levels (p<0.001) and was also higher in SAM than comparison children (median 959 vs 789 pmol/L), decreasing after treatment (median 815 pmol/L). TC was higher in children with SAM than comparisons but did not decrease after treatment. Overall, 23% of children with SAM had MMA levels suggesting B12 deficiency, compared to 4.5% of non-malnourished children.
Conclusion: In contrast to our initial expectations, we found that plasma B12 was higher in children with SAM, especially those with oedema. However, analysis of MMA revealed lower B12 function in malnourished children and improvement after treatment, warranting caution in the interpretation of plasma B12 in SAM. Elevated HC in SAM may explain the high B12 levels, but the cause of elevated HC needs further investigation.
背景：B12缺乏与神经发育受损和贫血有关，是严重急性营养不良（SAM）儿童的全球健康问题。目的：我们调查了SAM儿童和非营养不良儿童的B12状况，并评估了血浆B12测定的有效性。方法：本研究是营养干预试验研究的一部分。我们在营养治疗8周前后和非营养不良儿童的单一时间点测量了SAM儿童血浆中B12、甲基丙二酸（MMA）、总接触蛋白（HC）和总转钴胺素（TC）的水平。结果：纳入急性营养不良患儿82例，非急性营养不良患儿82例。SAM患者的血浆B12在入组时高于对照组（中位数为647 pmol/L vs 411 pmol/L），治疗后下降（中位数为469 pmol/L）。与无水肿的儿童相比，水肿性SAM儿童的基线血浆B12特别高（p=0.050）。相比之下，SAM患者的血浆MMA较高，反映出B12功能较低（中位数为220 vs 170 nmol/L），并且在治疗后下降（中位数为190 nmol/L）。结论：与我们最初的预期相反，我们发现SAM儿童的血浆B12水平较高，特别是水肿儿童。然而，MMA分析显示营养不良儿童的B12功能较低，治疗后有所改善，因此对SAM血浆B12的解释需要谨慎。SAM中HC升高可以解释高B12水平，但HC升高的原因需要进一步研究。
期刊介绍：
The Journal of Nutrition (JN/J Nutr) publishes peer-reviewed original research papers covering all aspects of experimental nutrition in humans and other animal species; special articles such as reviews and biographies of prominent nutrition scientists; and issues, opinions, and commentaries on controversial issues in nutrition. Supplements are frequently published to provide extended discussion of topics of special interest.
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