[Incidence of kernicterus in newborn infants in Denmark]

Kernicterus is an infrequent but serious complication of neonatal hyperbilirubinaemia. The purpose of this investigation was to describe the incidence of the condition in Denmark, its causes and its prevention. A follow-up was done to illustrate the serious consequences of this disease.

The study included all infants in Denmark born term or near term, with symptoms of classical kernicterus, in the period from 1977 to 2003.

From 1977 to 1993, no cases of kernicterus were reported. In the following period, from 1994 to 2002, eight patients were registered. The maximum plasma total bilirubin concentration was 531-745 mol/l. The aetiology was determined in two infants: spherocytosis and galactosaemia. Most likely, ABO blood type immunization was the reason in four cases. In two cases, the aetiology was unknown. Seven infants had symptoms of chronic bilirubin encephalopathy. One child had only minor signs of this condition. Seven were boys, and six infants were of Caucasian descent. Two of the infants died.

The incidence of kernicterus in Denmark is increasing, as in the rest of the Western world; this after a period of at least 20 years in which no cases were reported. A change in the assessment of the risk and inadequate knowledge of the serious consequences of bilirubin encephalopathy may be explanations. Through information and education of health personnel, it is possible to provide sufficient information to parents, perform screening procedures and commence therapy at the appropriate time. This could possibly contribute to a reduction in the incidence of the disease and its serious consequences.