My gyn noticed a "bump" in my creatine level and asked how my kidney function was. i was unawear. could a low carb diet be the cause?

NO: Creatinine levels can fluctuate and tend to increase to a certain degree with high protein diet, creatine supplements etc. If the creatinine increase is more than 30 % then you need evaluation by nephrologist. My advise is to recheck the creatinine level after adequate hydration first.

Bump in creatinine: Your question would be bettered answered with some more information. What was the creatinine (c) level and how big was the "bump" (b)? What was the time interval between the 2 tests that had different (c) levels? A difference in c of 0.2 mg over a year is not a big bump. The c level is also dependent on one's sex, age, race and body weight. I do not think that a low carb diet is the cause of b.