Two infants with a florid erythematous rash and generalised oedema, hypoalbuminaemia, and anaemia were found to have cystic fibrosis. This rare presentation is associated with false negative sweat tests, delays in diagnosis, and a considerable mortality. It is proposed that this presentation represents a manifestation of kwashiorkor secondary to malabsorption. The recognition that these infants have kwashiorkor provides some insight into the pathogenesis and management of their illness.