1H NMR spectroscopic study of blood serum for the assessment of liver function in liver transplant patients.

BACKGROUND AND AIMS: Plausible reasons for the failure of liver graft in liver transplantation are explored. 1H-NMR spectroscopy of serum is employed for assessment of liver graft function. Differences in concentrations of specific metabolites between patients with successful and unsuccessful liver grafts following transplantation were used as possible markers to assess the graft quality.
METHODS: Blood samples from the patients undergoing liver transplantation were obtained preoperatively, immediately after transplant followed by every 24 hrs of post-transplantation until patients were discharged or expired. 1H-NMR spectroscopic studies of serum were performed at each time point and concentrations of various metabolites measured. Conventional biological tests were also performed at each time point.
RESULTS: Elevation of concentrations of the nine metabolites (lactate, alanine, lysine, glutamine, methionine, asparagine, tyrosine, histidine and phenylalanine) in non-survivors using NMR was attributed to the graft dysfunction. The information on the graft dysfunction using conventional biological tests was obtained much later. However, elevation in aminotransferases and bilirubin levels was indicated after about one week and 3 days respectively in non-survivors. Hepatic failure causes alteration in the concentrations of amino acids due to impairment of amino acid metabolism and urea cycle. 1H-NMR spectroscopy provides the information of all the metabolites in a single step without involving any chemical pretreatment implying better accuracy since each step involved can introduce its own experimental error.
CONCLUSION: Distinct metabolic profile in non-survivors compared to survivors following transplantation promises potential of 1H-NMR studies in the assessment of liver graft function.