Quantification of major urinary metabolites of PGE2 and PGD2 in cystic fibrosis: Correlation with disease severity

Cystic fibrosis transmembrane conductance (CFTR) alterations are involved in the overproduction of prostaglandins (PG) in CF in vitro. We assessed the relationship between PGE-M and PGD-M urinary metabolites of PGE2 and PGD2 and CF severity. Twenty-four controls and 35 CF patients were recruited. PGE-M and PGD-M levels were measured by liquid chromatography/mass spectrometry and results were expressed as median and 25th–75th interquartile of ng/mg creatinine (Cr). PGE-M (15.63; 9.07–43.35 ng/mg Cr) and PGD-M (2.16; 1.43–3.53 ng/mg Cr) concentrations were higher in CF than in controls: PGE-M, (6.63; 4.35–8.60 ng/mg Cr); PGD-M (1.23; 0.96–1.54 ng/mg Cr). There was no correlation between metabolite levels and spirometric values. Patients with pancreatic insufficiency (n=29) had higher PGE-M levels (19.09; 9.36–52.69 ng/mg Cr) than those with conserved function (n=6) (9.61; 5.78–14.34 ng/mg Cr). PGE-M levels were associated with genotype severity: mild (7.14; 5.76–8.76, n=8), moderate (16.67; 13.67–28.62 ng/mg Cr, n=5) and severe (22.82; 10.67–84.13 ng/mg Cr). Our study confirms the key role of CFTR in the regulation of the cyclooxygenase pathway of arachidonic acid metabolism found in in vitro studies.