Conjugated hyperbilirubinaemia as the first manifestation of mevalonic aciduria in a term newborn

To present clinical and laboratory findings in the case of a term newborn with conjugated hyperbilirubinaemia and to stress the importance of differential diagnosis. A term newborn delivered by caesarean section (birth weight 2550 g, birth length 47 cm, value of Apgar score 9/10) with good direct adaptation had on the first day of life increased levels of conjugated bilirubin (23 micromol/l), unconjugated bilirubin (55 micromol/l) and C-reactive protein 39.4 g/l. The diagnosis of mevalonic aciduria was confirmed by urine analysis (mevalonolactone 393 micromol/mmol crea, normal range