The role of lactic acid in the reduced excretion of uric acid in toxemia of pregnancy.

Wlhen Chesley and Williams demonstrated low uric acid excretion in toxemiiic patients,1 they noted that the reduction in renal urate clearance was relatively greater than the reduction in glomerular filtration rate (1). This relationship has been confirmed (2) and is striking when c-ompared with observations on urate excretion in normal slibjects and patients with renal disease. It is generally accepted that tunder normal circtumstances serum urate is completely filtered at the glomertulus and that 5 to 10 per cent of filtered turate appears in the urine (3) ; net tubular reabsorption accounts for the other 90 to 95 per cent. Coombs and co-workers (4), in a sttudy of subjects with various degrees of renal imiipairment, found that as glomerular filtration rate fell, a progressively larger portion of filtered urate was excreted in the urine, uric acid clearance increasing to over 20 per cent of glomerular filtration rate. In preeclamptic and eclamptic patients, althotugh glomerular filtration rate is reduced, the ratio of urate clearance to glomerular filtration rate is often lower than normal. Unless there is a redtuction in the filtrability of serum turate, explanation of the low ratio of uric acid clearance to glomiiertular filtra-