Uncontrolled BG levels will almost always lead to compromised kidney
function. That said, a high BG one day will not led to a high serun
creatinine level that day. Over time, a person with uncontrolled BG (an
HbA1c of 8% or higher) is much more likely to experience diabetic
nephropathy than a person with a well-controlled BG (not set in stone,
however; a peson with perfect control can still have DN). The usual
course of kidney dysfunction in diabetics is an initial period of
'hyperclearance,' with a very low serum creatinine and a very high
24-hour urine creatinine as the kidneys are overclearing - as one bok
puts it, burning themselves out. During this time, the patient may also
begin to have albumenuria or frank proteinuria. After a period (which
can be years), the kidneys 'slow down' and the serum creatinine creeps
up while the urine creatinine goes down.

In short, controlling BG to as close as possible to normal (that is,
non-diabetic levels) in diabetics can help prevent or slow down the
progress of diabetic nephropathy, but day-to-day BG and serum creatinine
levels aren't that closely linked. If you go in with a BG of 220 today
and your serum creatinine is .7 and tomorrow your BG is 120, your serum
creatinine is likely again to be .7. Dehydration, overexertion and
overconsumption of caffienated drinks (at least according to the lab
hand-outs I'm given) are more likey to have an immediate effect on serum
creatinine results.

Erm, not sure what you're asking, but if the serum creatinine is high,
then no, nothing is compensating. If the serum creatinine is outside the
normal range, a nephrologist needs to be consulted for, among other
things, dietary restrictions appropriate to the patient.

If this query is about your lab results and BG, be sure to ask your
doctor for information, guidance and advice. Kidney disease is nothing
to play around with.