Update Milo 3.38pm Friday

Vet called. Bill so far is $735. Paid $385 last Saturday to local vet. Total $1100. But it includes many blood tests, consults, ultrasound, biopsy and of course ther new donut bed and catnip spray :)

Vet just emailed and said Milo was very happy in his new donut bed with catnip spray and has been kneading it all afternoon. I feel so much better now. I feel so sorry for him being away from home. He has never been away from home overnight before.

Creatinine (From wikipedia http://en.wikipedia.org/wiki/Creatinine)
Creatinine is a break-down product of creatine phosphate in muscle, and is usually produced at a fairly constant rate by the body (depending on muscle mass).
Creatinine is mainly filtered by the kidney, though a small amount is actively secreted. There is little-to-no tubular reabsorption of creatinine. If the filtering of the kidney is deficient, blood levels rise. As a result, creatinine levels in blood and urine may be used to calculate creatinine clearance (ClCr), which reflects the glomerular filtration rate (GFR). The GFR is clinically important because it is a measurement of renal function. However, in cases of severe renal dysfunction, the creatinine clearance rate will be overestimated because the active secretion of creatinine will account for a larger fraction of the total creatinine cleared.
A more complete estimation of renal function can be made when interpreting the blood (plasma) concentration of creatinine along with that of urea. In the USA, urea concentration is given as blood urea nitrogen (BUN), in mg/dL. In other countries, including those of Europe, urea concentration is measured and quoted in mmol/L.
The ratio of urea to creatinine can indicate other problems besides those intrinsic to the kidney. For example, a urea level raised out of proportion to the creatinine may indicate a pre-renal problem such as dehydration.