What is the primary purpose of monitoring serum creatinine in infants?

Monitoring serum creatinine in infants primarily serves to assess kidney function. Creatinine is a waste product produced from muscle metabolism, and its levels in the bloodstream indicate how well the kidneys are filtering blood.

In infants, which can have varying levels of muscle mass and development, tracking creatinine is crucial, particularly as it provides insight into renal health and can help detect kidney disease or dysfunction. An elevated serum creatinine level may signal underlying issues with kidney filtration, which is critical for maintaining overall health, particularly in a developing infant.

While the other options pertain to assessing functions in different organ systems—such as liver function, heart function, or hydration status—serum creatinine specifically reflects renal function and is a standard marker used in both pediatric and adult medicine to evaluate how well the kidneys are performing their role in excreting waste.