Normal creatinine levels for each child can vary depending on their body size. So, the creatinine levels indicating kidney failure can also vary in children. Pediatric nephrologists (kidney specialists) assess the creatinine levels with child size to establish the diagnosis. For example, if the normal creatinine level for a child with a specific size is 0.5, the child’s kidneys are in 100 percent working condition. Kidney function can be half for the same child if the creatinine level rises to one. If the creatine is between one and two, kidney function would be only 25% (17).