Identification of the causes of persistent hyperuricaemia.

Accurate identification of the factors that contribute to hyperuricaemia in an individual may enable some of these factors to be modified, and lead to permanent correction of the hyperuricaemia. A protocol is described which can supplement clinical assessment. Measurement of the effects on serum urate and urinary urate excretion of a low-purine diet for 7 days facilitates the identification of the contributions made by urate production (either endogenous or from purine consumption) and renal underexcretion of urate (either as a low urate clearance in the absence of renal disease or due to renal glomerular insufficiency).