Dalteparin-sodium induced drug fever in a neonate.

Drug fever caused by dalteparin-sodium (DS), a low-molecular-weight derivative of heparin, is neither listed in the official drug information and nor published as a case report until today. A preterm infant, born at 26 weeks of gestation, developed fever 2 days after starting a treatment with DS for an intracardial thrombus. The fever reverses soon after changing the treatment to unfractionated heparin and reappeared after reintroduction of DS. Once again, after discontinuing DS, the infant regained normothermia. Bacterial and viral infections, tissue damage, impaired liver or kidney function, preservative agents and comedications could be ruled out as fever origin. By using the Naranjo adverse drug reaction (ADR) probability scale and the Liverpool ADR causality assessment tool, this case can be classified as 'probable ADR' and 'definite ADR'. This is the first case report of a drug fever caused by the low-molecular-weight heparin DS in a preterm infant.