Dear Shannon
I was being my autistic self and reacting to
"some urine test that could indicate whether the kidneys are emptying
fully... "
I think the test is done by using contrast medium and it shows the passage
of the material through the urinary system. But it is not like a barium meal
which is X-ray opaque. I think this stuff is Radio Active and they measure
the radio-activity build up.
The material has a short half life so with a short passage of time it has
left the body.
Indeed when there is ureter of bladder pathology, the whole of the volume
from the kidney to the bladder fills up and allows bacteria that have
travelled from urethra to the bladder to go to kidneys. So extreme hygiene
(and use of a bidet after urination) is very important as I had expressed
before.
Another source is of course micro organisms coming to the kidneys via the
blood that goes through them. But these normally react quickly when A/B are
administered.
It must be noted that the urinary system is usually sterile. But when the
micro-organisms enter the urinary tract via the urethra - because there is
little blood flow, A/Bs are not all that effective, especially as they are
also countered by the chemicals present in urine.
Rgds
Soroush