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Hello Jane

First they will almost certainly do full testing tomorrow, the nurse takes urine at once, and things might have changed. Second, all test results have to be interpreted along with other test results and other findings

The ANA 1:40 is the weakest reportable level and makes lupus less likely as many perfectly healthy people have low levels and it can be slightly raised for reasons other than lupus. It does not exclude a lupus diagnosis -there may be other far more important findings. ANA levels can vary very very much over time even in diagnosed people.

As for the GFR, it's used as a measure of kidney function. Here's one reliable site's description of it. According to this, that GFR is probably fine whch would be why the GP didn't follow up. However it's a good idea to have frequent urine and other tests in the early years after diagnosis. Although I have blood tests every few months for side effects of meds my GP wasn't ordering a urine test so I simply asked for one. It is most unlikely that I will develop kidney disease at this late stage in my lupus but I want to keep an eye on UTI's as well because I tend to have symptomless ones which would go undetected otherwise. But kidney disease doesn't have symptoms until quite advanced so the sooner problems are detected by a simple test the better.

Your doctor can measure the level of creatinine by doing a simple blood test. A normal adult creatinine is about 1.0, regardless of age. We use the level of creatinine to determine the “glomerular filtration rate” or “GFR” – in other words, how well the glomeruli (those tiny filters in the kidneys) are filtering out waste products. The GFR is calculated using a mathematical equation, or sometimes by having you collect urine for 24 hours and measuring how much creatinine is in the urine. The 24-hour urine test is called the “creatinine clearance” and is similar to the GFR.
Kidney function normally declines as we age, so even though the normal blood creatinine is still 1.0 when you are 70-years old, the kidneys filter waste products less efficiently than when you were age 20. The higher the GFR, the better the kidney function. A GFR of 60-100 is generally considered normal (depending on your age and whether you are male or female). Most people do not have symptoms of decreased kidney function until the GFR is 20-30 or less, and some people don’t feel sick until the GFR is as low as 10-15. It is important for anyone with kidney disease to “know your GFR number” and once you know your blood creatinine, you can even calculate your own GFR by using the GFR Calculator on this website. (Go to’s GFR Calculator to learn your GFR.)

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