[Severe hypernatraemic dehydration in collodion baby].

Case report on severe hypernatraemic dehydration in a non-recognised collodion baby who also suffered from hydrops fetalis caused by supraventricular tachycardia. Excessive transcutaneous fluid loss caused s-Na+ reaching 182 mmol/l within 36 hours of birth. The infant was cautiously rehydrated during the following three days. No sign of neurologic impairment was observed. It is emphasized that early observation of the collodion baby must take place in a humidified incubator. Major weight changes in the newborn should always result in analysis of serum sodium.