UCL Discovery

Abstract

Background-In vivo hepatic phosphorus-31 magnetic resonance spectroscopy (P-31 MRS) provides biochemical information about phosphorus metabolism.Aim-To assess P-31 MRS as a prognostic marker in patients with primary biliary cirrhosis (PBC) in relation to the current clinical prognostic models.Patients and Methods-Twenty three patients with PBC of varying functional severity and 16 matched healthy volunteers were studied using in vivo P-31 MRS. Spectra were acquired using a 1.5 T spectroscopy system. Peak area ratios of phosphomonoesters (PME), inorganic phosphate (Pi), and phosphodiesters (PDE) and nucleotide triphosphate (NTP) were calculated. Pugh score, Christensen prognostic index, and R value according to the Mayo model were calculated from the clinical data.Results-The PME/NTP, Pi/NTP, PME/PDE, and PME/Pi ratios and the PME signal height ratio (SHR) were significantly higher, while the PDE/NTP and PDE/SHR were significantly lower in PBC patients compared with healthy volunteers (p<0.01). Significant correlations were seen between PME/Pi ratio and the prognostic index according to Christensen (r=0.63, p<0.001), R value according to the Mayo model (r=0.45, p<0.03), and with the Pugh score (r=0.55, p<0.007).Conclusions-This study shows that PME/Pi ratio obtained from P-31 MRS correlates well with all three of the commonly used models of prognosis in patients with PBC. A longitudinal study with larger number of patients is required to confirm these findings and elucidate the biochemical changes underlying this phenomenon.