Impairment of Uric Acid Excretion in Gout*

Abstract

The urinary excretion of uric acid in individuals with primary gout has been shown to be approximately the same as, or in a minority of instances greater than, that of normal subjects on comparable diets (2, 3). These observations, plus the failure to demonstrate significant differences in the renal clearance of uric acid in gouty and nongouty control subjects, have led to the conclusion that patients with gout excrete uric acid in a normal manner (2-5).This view has, however, recently been challenged (6) on the ground that in the studies on which it was based, differences in the plasma urate concentrations of gouty and nongouty subjects were not taken into account. In order to eliminate such differences Nugent and Tyler (6) induced hyperuricemia in nongouty individuals by the oral administration of uric acid precursors and compared uric acid excretion in these subjects and patients with gout. Under these conditions an impairment in urate excretion was clearly evident in patients with gout; both the excretion and clearance of urate were significantly less than in nongouty subjects with equivalent plasma urate levels.These observations of impaired uric acid excretion were fully supported by the present study, in which urate was administered intravenously to gouty and nongouty subjects in order to a) study urate excretion at equivalent and various plasma levels and b) examine the dynamics of the renal tubular transfer mechanisms for urate.

Obliteration of Intracranial Aneurysms by Pilojection

“…These observations support suggestions previously made4 5 10 They found that at normal levels of urate in the plasma there was no significant difference between the gouty and control subjects in the excretion of urate. But at higher plasma levels of urate all but one of the gouty patients showed impairment of excretion when compared with the controls.…”

Uric acid clearance in patients with gout and normal subjects.

“…of the control value. Following this, a number of studies attempted to assess the effect of added loads of uric acid in gouty and normal subjects and it became evident that both groups were able to increase their rate of clearance in such circumstances (Nugent and Tyler, 1959;Lathem and Rodnan, 1962;Gutman, Yu, and Berger, 1969). Data from the present study, however, indicate a rather greater difference in mean clearance figures, values for gouty patients (3 9 ml./min.)…”

URINARY pH IN GOUT

“…In considering the pathogenesis of this loss of diurnal rhythm for urinary pH, it is uncertain whether the excretion of acid urine throughout the day and night is primary, as part of the disturbance of uric-acid metabolism in gout, or secondary to renal damage. There has always been a controversy as to whether the renal handling of uric acid plays a primary role in the pathogenesis of gout, and recently there has been more evidence to support this concept (Nugent and Tyler, 1959 ;Lathem and Rodnan, 1962). It would not be surprising, then, to find disturbances of other tubular functions.…”