1454 A PATHOLOGIC REAPPRAISAL OF KERNICTERUS

Abstract

Kernicterus, or bilirubin staining of specific nuclei of the brain in newborns, is traditionally considered to represent a deleterious manifestation of hyperbilirubinemia. All infants (32) from January, 1970 through January, 1977 found at autopsy to have characteristic gross bilirubin staining were identified. They were matched with 32 other infants without gross staining for gestational age, weight, length of survival and year of birth. In our initial clinical review we found no differences when multiple factors thought to potentiate risk for kernicterus were compared between the matched pairs. The neuropathologic changes in these two groups were evaluated without knowledge of the clinical or gross findings. While the pattern of gross bilirubin staining followed that classically described for kernicterus, specific histologic changes were found in only two kernicteric and one non-kernicteric infant. The nonspecific finding of diffuse spongy change was more common in the grossly stained brains (p<0.05), but other histologic findings did not differ significantly between the two groups. In the current population of newborns the majority of bilirubin staining in the brain at autopsy may be secondary to prior nonspecific damage, rather than an indication of bilirubin toxicity. Our results emphasize that this yellow staining as seen today, while grossly indistinguishable, is not equivalent to the classical kernicterus of previous years.