Observations on Uricolysis, with Particular Reference to the Pathogenesis of “uric Acid Infarcts” in the Kidney of the New-born.’

The fact that deposits of urates are found in the collecting tubules of the kidneys of about one-half of all infants dying during the first two weeks of life, indicates that, in all probability, similar deposits occur frequently in normal infants. Consequently, it must be assumed that such deposits are not often a source of any harm, which assumption accounts for the relatively slight consideration given to these so-called “uric acid infarcts of the new-born.” Nevertheless, it seems improbable that deposition in the renal tubules of masses of crystals of ammonium urate can always fail to cause injury, for in the first place these substances are not altogether non-toxic, if we accept the results of the studies of Freudweiler,2 His3 and others who have shown that urates cause local necrosis and act as weak tissue poisons. Furthermore, the very slight solubility of uric acid and the urates insures their remaining in the tubules for some time after they are once deposited ; Kaufmann indeed mentioning their persistence for years, finding them in one case in a boy seven years old. Certainly they may serve as the starting point of urate calculi, which occur not infrequently in young children, and it seems not improbable that injury to the renal tissue by these deposits may serve as a starting point for infection. Suppurative pyelitis in infants and young children has been frequently observed, due