Effect of blood contamination of cerebrospinal fluid on amino acids, biogenic amines, pterins and vitamins

Abstract

BackgroundCerebrospinal fluid (CSF) metabolomic investigations are a powerful tool for studying neurometabolic diseases. We aimed to assess the effect of CSF contamination with blood on the concentrations of selected biomarkers.MethodsCSF samples were spiked in duplicate with increasing volumes of whole blood under two conditions: (A) pooled CSF spiked with fresh whole blood and frozen to cause red blood cell (RBC) lysis; (B) pooled CSF spiked with fresh blood and centrifuged (the supernatant with no RBCs was frozen until the moment of analysis). CSF concentrations of amino acids, biogenic amines, pterins, and vitamins were analysed by HPLC coupled with tandem mass spectrometry, electrochemical and fluorescence detection.ResultsAspartate, glutamate, taurine, ornithine, glycine, citrulline, pyridoxal 5´-phosphate, 5-methyltetrahydrofolate, and thiamine showed higher values when RBCs were lysed when compared with those of CSF with no RBC, while arginine, 5-hydroxyindoleacetic and homovanillic acids showed lower values. When RBCs were removed from CSF, only some amino acids, thiamine and pyridoxal 5´-phosphate showed moderately higher values when compared with the non-spiked CSF sample.ConclusionsCSF-targeted metabolomic analysis is feasible even when substantial RBC contamination of CSF has occurred since CSF centrifugation to remove RBC prior to freezing eliminated most of the interferences observed.

Point-of-care detection of lactate in cerebrospinal fluid

“…Almost half of our patients had suffered from subarachnoid hemorrhage often introducing a high amount of blood into CSF. Correspondingly, while blood contamination affects CSF concentrations of amino acids and a group of vitamins only mildly [ 16 ] it influences CSF protein diagnostics [ 17 ]. Still, in a more experimental setting the addition of different amounts of blood to otherwise normal CSF of 33 adults did not influence the lactate level significantly, but led to higher glucose measurements [ 18 ].…”

Point-of-care Detection of Lactate in Cerebrospinal Fluid

“…Almost half of our patients had suffered from subarachnoid hemorrhage often introducing a high amount of blood into CSF. While only mild effects of blood-contamination on CSFconcentrations of amino-acids and a group of vitamins were found [16] blood contamination in uences CSF protein diagnostics [17]. Still, in a more experimental setting the addition of different amounts of blood to otherwise normal CSF of 33 adults did not in uence the lactate level signi cantly, but led to higher glucose measurements [18].…”

Development of a translational inflammation panel for the quantification of cerebrospinal fluid Pterin, Tryptophan-Kynurenine and Nitric oxide pathway metabolites

“…Furthermore, CSF blood contamination can cause misinterpretations of data analysis and metabolic profiles. 44 The results for matrix effects investigated at three haemoglobin concentration levels (12, 6 and 3 g Representative extracted ion chromatograms of the targeted metabolites in human cerebrospinal fluid. (a) Metabolites prepared using the MPA/EDTA solution sample preparation method: 1 quinolinic acid, 2 kynurenine, 3 xanthurenic acid 4 3-hydroxyanthranilic acid 5 tryptophan and 6 kynurenic acid.…”