Urinary prostaglandin and prostaglandin metabolite excretion in patients with essential hypertension or hypertension with renal artery stenosis.

BACKGROUND Recent studies have reported elevated prostaglandin levels in patients with renal artery stenosis and hypertension. To investigate whether a distinction between essential hypertension and hypertension with renal artery stenosis is possible by measuring eicosanoid excretion, we studied the excretion of these compounds in patients with essential hypertension and in hypertensives with concomitant renal artery stenosis. METHODS The 24-h urinary excretion of metabolites of prostaglandin I2, prostaglandin E2 and metabolites of thromboxane A2 was sampled under standardised conditions, in 15 patients with essential hypertension and in 15 patients with unilateral renal artery stenosis with hypertension. Also clinical and biochemical characteristics of the subjects were analysed. RESULTS The patients with renal artery stenosis had significantly lower excretion of prostaglandin I2 than did the essential hypertensive patients. However, the overlap in the values was large, thus not allowing a diagnostic differentiation according to urinary prostaglandin I2 levels. The excretion of prostaglandin E2 and of metabolites of thromboxane A2 showed no significant differences among the groups. CONCLUSIONS Measurement of urinary prostaglandin or prostaglandin metabolite excretion did not contribute to the non-invasive detection of the presence of a renal artery stenosis in the patients in this study.