Uric acid infarctions in the kidneys of newborn infants. A study on the changing incidence and on oxypurine ratios.

Among 1115 newborns who died during 1957--1976, 136 (12.2%) showed macroscopic renal uric acid infarctions. The incidence depended on the age of the infants and their fluid supply during the first days of life. After introduction of parenteral alkali-glucose infusion in the treatment of perinatal complications, the incidence of renal uric acid infarctions decreased from 19.3% to less than 1.0%. Analysis of the oxypurines in the renal uric acid infarctions of three newborns revealed high percentages of hypoxanthine (31.1%, 21.8% and 11.0%) along with the uric acid. Hypoxanthine ratios above 15% retrospectively point to chronic hypoxia of the newborn.