Establishment of the reference ranges for amino acids and acylcarnitines in cerebrospinal fluid of children

Abstract

Objective To establish the reference values for some amino acids and acylcarnitines in cerebrospinal fluid of children, and provide evidence for the diagnosis of inherited metabolic diseases. Methods Retrospective study was made on 152 children with epilepsy collected from 2010 to 2014 in Xinhua Hospital Affiliated to Shanghai Jiaotong University School of Medicine. The levels of amino acids and acylcarnitines in the cerebrospinal fluid of these children were detected by tandem mass spectrometry, with their correlation with age and gender analysed, and their differences between blood and cerebrospinal fluid in 60 children were observed. Variance, Wilcoxon rank sum test and Spearman correlation were used for data analysis. Results These normal reference values of amino acids and acylcarnitines in cerebrospinal fluid of children were established.The Methionine and glutarylcarnitine levels in blood and cerebrospinal fluid had no difference [Methionine: 18.66(15.24-24.11) vs 23.41(13.80-28.58) μmol/L, glutarylcarnitine: 0.03(0.02-0.04) vs 0.03(0.02-0.04) mol/L], (Z=-0.69, -0.09, all P>0.05). The arginine levels in blood was 3.82(2.00-8.36) μmol/L, which was lower than cerebrospinal fluid [38.37(34.15-48.41) μmol/L], (Z=-6.74, P<0.05), while the other 9 kinds of amino acids and 13 kinds of acylcarnitines were higher in blood (all P<0.05). Conclusions The normal reference levels of amino acids and acylcarnitines in cerebrospinal fluid of children have been established, which may play a essential role in the diagnosis of inherited metabolic diseases.(Chin J Lab Med, 2015, 38: 251-255) Key words: Amino acids; Carnitine; Cerebrospinal fluid; Reference values; Child