Elevated Serum Creatinine: But Is It Renal Failure?

Serum creatinine is typically used to evaluate kidney function. Yet, it is a marker that can only provide estimations of kidney function because it can be influenced by other factors, such as dietary intake. The expanding field of infant formula selection in recent history has given many options for parents who are unable to provide breastmilk. Standard infant formulas and breastmilk generally fall within a select range of creatine content. With greater accessibility to internet-based medical advice (licensed or unlicensed), parents and families have more chances to be exposed to opportunistic websites and opinions that may provide harmful information. In this report, we describe the case of excessive dietary creatine intake in an infant who presented with elevated creatinine while otherwise appearing healthy and having normal cystatin C. After in-depth evaluation of nutritional intake, there was a suspicion for high creatine load of the infant's homemade formula, which was composed of beef liver and various unregulated nutritional powders. Within 12 hours of stopping the infant's homemade formula and providing intravenous fluids, the infant's creatinine normalized. We highlight the importance of in-depth nutrition assessments and education on the health risks associated with improper formula selection.