Abstract In this study, the levels of concentration of carboxylic acids (benzoic acid, p-hydroxybenzoic acid, p-hydroxyphenylacetic acid, and hippuric acid) in the urine of autistic children were investigated and compared. The increased excretion of carboxylic acids is related to excessive bacterial activity in the gut, called bacterial overgrowth, which has been related to autism spectrum disorder (ASD) as an impairment in the gut-brain axis. The investigation was based on the analysis of urine samples obtained from 120 ASD children. To identify and quantify urinary carboxylic acids (UCAs), we applied gas chromatography coupled with mass spectrometry (GC-MS). Additionally, we checked the influence of probiotic supplementation, gender, body mass index (BMI) value and age of children on the level of different selected compounds. Most of the obtained results were found within reference ranges. In some cases, the levels of benzoic acid, p-hydroxybenzoic acid, and p-hydroxyphenylacetic acid were particularly elevated. Statistically significant differences were observed in supplementation with probiotics and the level of p-hydroxyphenylacetic acid (p=0.036). The obtained results may indicate disturbances in the intestinal flora in some autistic patients and suggest that supplements may have an influence on the levels of carboxylic acids in urine. Due to the small population of children taking the supplement, further study are needed.

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自闭症谱系障碍患者的尿羧酸 (UCA) 及其与细菌过度生长的关系

摘要 本研究对自闭症儿童尿液中羧酸（苯甲酸、对羟基苯甲酸、对羟基苯乙酸和马尿酸）的浓度水平进行了调查和比较。增加的羧酸排泄与肠道中过度的细菌活动有关，称为细菌过度生长，这与自闭症谱系障碍 (ASD) 作为肠-脑轴受损有关。该调查基于对 120 名 ASD 儿童尿液样本的分析。为了鉴定和量化尿羧酸 (UCA)，我们应用了气相色谱与质谱联用 (GC-MS)。此外，我们检查了益生菌补充剂、性别、体重指数 (BMI) 值和儿童年龄对不同选定化合物水平的影响。大多数获得的结果都在参考范围内。在某些情况下，苯甲酸、对羟基苯甲酸和对羟基苯乙酸的含量特别高。在补充益生菌和对羟基苯乙酸的水平上观察到统计学上的显着差异 (p=0.036)。获得的结果可能表明一些自闭症患者的肠道菌群紊乱，并表明补充剂可能对尿液中的羧酸水平产生影响。由于服用补充剂的儿童人数较少，需要进一步研究。在补充益生菌和对羟基苯乙酸的水平上观察到统计学上的显着差异 (p=0.036)。获得的结果可能表明一些自闭症患者的肠道菌群紊乱，并表明补充剂可能对尿液中的羧酸水平产生影响。由于服用补充剂的儿童人数较少，需要进一步研究。在补充益生菌和对羟基苯乙酸的水平上观察到统计学上的显着差异 (p=0.036)。获得的结果可能表明一些自闭症患者的肠道菌群紊乱，并表明补充剂可能对尿液中的羧酸水平产生影响。由于服用补充剂的儿童人数较少，需要进一步研究。