I'm on my way, I hope, toward the new, highly sensitive and accurate feraheme USPIO MRI scan to spot any prostate cancer in lymph nodes, as I've mentioned in other posts. (I'm on my way toward a possible shot at a cure in my thirteenth year since diagnosis of a very challenging case of prostate cancer.) My first major step was the Na 18F PET bone scan, a sensitive type of scan that showed no bone mets, as I've also mentioned in other posts.
However, that scan revealed a likely benign "adrenal incidentaloma" - honestly, that's the official name, and I've now had my second test to workup that issue. It was supposed to be a CT scan with and without contrast, and I followed the few preparation instructions to the letter. However, I wish I'd been given a couple more instructions.
I did have a CT scan without contrast, but the center was unable to do the contrast part, which requires an IV, because my creatinine level was too high. I felt blindsided and disappointed.
Creatinine is used as an indicator of kidney trouble, because the kidneys clear creatinine from the blood. If the level is high, it suggests that the kidneys are not functioning well, and that can be a problem with the CT contrast agent that is delivered by the IV as it may not be cleared out of the body well enough. Contrast is also known, I've just learned, to increase the creatinine level all by itself.
I'm actually learning about creatinine for the first time, having retained only a vague recollection of what I had read about it. It's likely that those of us with kidney issues know all about it, but my levels, tested just about every two months for years as part of a battery of blood tests, have always been right around 1.0, which is excellent. In fact my last test in November was 1.1, slightly elevated for me but well below the upper end of the reference range, which is 1.4 for the test version my doctor's lab uses. That's why I had never been concerned about creatinine.
Well, the technician got a reading of 1.7 just before the CT scan, and the same reading on a repeat, too high for him to give me the contrast, which he confirmed with the radiologist.
While I might have a serious kidney issue, that seems a remote possibility as I think I've doped out what happened. Yesterday I learned that creatinine goes up when muscle tissue is injured, as happens routinely in weight lifting and heavy physical exertion, which, after recovery, leads to increased muscle strength. The day before I had hauled a lot of heavy items around, and the night before the scan I was as sore as I had been for months, indicating muscle tissue injury. I suspect that accounted for some of the unusual increase in creatinine. I've also learned that the supplement creatine monohydrate - a favorite among muscle builders and for many athletes - can affect creatinine levels - no Sherlock Holmes needed to see that connection. I had started daily creatine supplementing in mid-September, and I had added a teaspoonful to my orange juice about five hours before the technician did the blood test. Therefore there are two likely causes for my elevated creatinine level, and I can take care of both before my next CT scan with contrast.
That is going to be my last dose of creatine for a while. After talking to a couple of supplement maker reps yesterday, I've learned that it's wise to use creatine intermittently - say a month on and a month off, at least for me, in order to avoid a build-up. It would have been nice for the makers to mention that on the label.
It would also have been nice for the radiology lab to ask about creatine use and explain that I would be pre-screened with a creatinine blood test.
While they were at it, they could have also advised me to avoid heavy muscle exertion for a few days.
The lab I hope to go to in Florida for the feraheme scan actually does advise patients to avoid heavy exertion for several days, but I did not understand the reason, and I figured their scan used a different technology, thereby requiring different prep. Now I understand what they are aiming for.
I'm sadder but wiser. On the other hand, I'm grateful to learn about the creatinine buildup from taking creatine monohydrate.
Has anyone else run into this issue with creatinine? Is anyone else using the supplement creatine?
I guess I've just taken another course in the Medical School of Hard Knocks.