Creatinine levels will almost definately become elevated through use of creatine supplementation. But as others have suggested as a bodybuilder or someone who does very physical work etc your normal parameters can be very different to the average joe's. I had mine checked not so long ago and my doc started monitoring it. I then discontinued using creatine and my creatinine levels dropped back to what is considered mainstream normal within about 3-4 weeks.
Just to mention also that when I take creatine I never load it and only ever take about 1/2 a teaspoon with water prior to working out (when I remember) so probably about two full teaspoons a week. That is plenty for me even at some 270 pounds as I gain around 6-7 kilos from that in 1 - 2 weeks.
After using it for around 3-4 weeks I stop ingesting it and keep off it for at least the next 3-4 weeks. That's my experience anyways.
