Is kernicterus always the definitive evidence of bilirubin toxicity

Concluding an extensive clinical and pathologic study of 126 cases of kernicterus, Gerrard wrote in 1952: "The pigmentation of the brain is secondary to the nerve cells being first damaged by a factor or factors unknown."1 This opinion was shared by most of the experts of this period. Systematic measurements of bilirubin levels in jaundiced newborns were not part of their management. In the absence of such measurements the jaundiced babies with kernicterus did not appear to be different from the larger number of jaundiced newborns without kernicterus.