FineLetMeSayIt OP t1_j9qbfjw wrote on February 23, 2023 at 8:28 PM

Reply to comment by lascivious_boasts in How can Doctors tell if one of your kidneys isn't working? by FineLetMeSayIt

Thank you for such a wonderfully detailed response! I guess barring an anomaly on your tests, doctors would never think to look for single sided kidney failure. I don't know enough about kidney diseases, but I thought about this because of a coworker/acquaintance who currently has to undergo dialysis. In laymen's logic, it would seem unlikely BOTH of her kidneys failed at the same time. Which means at some point one kidney was doing the job of two, but nobody noticed.

lascivious_boasts t1_j9qe4vg wrote on February 23, 2023 at 8:45 PM

It's actually much more common for both kidneys to fail together.

The underlying causes of kidney failure tend to be systemic (that is affecting the whole body) rather than local.

The big one is diabetes, and barring a blockage in blood supply to one kidney, the main damage is in all the tiny blood vessels that feed each nephron. This usually happens equally between both sides (although occasionally the renal artery stenosis is more of a problem, in which case one side can get a stent to try to maintain its function).

Other big causes are inflammatory/autoimmune. This means anywhere there's a kidney cell/structure the damage occurs. Broadly, this affects both sides at the same time.

fiendishrabbit t1_j9tmiei wrote on February 24, 2023 at 1:59 PM

Though not always. Had a colleague with hereditary PKD and an asymmetric progression (left kidney, non-functional and a huge amount of scar tissue. Enough that they had to remove it when transplanting. Right kidney had been pulling all the weight for the last few years and was now failing as well).

puahaha t1_j9qgvnh wrote on February 23, 2023 at 9:02 PM

Kidney failure is also sinister because you can be asymptomatic even while function is declining until it's really bad, like less than 20~30% functionality. So not only is compensatory action like one kidney fulfilling the role of the other at play, both will have to fail to a very significant degree before you even notice.

paceminterris t1_j9t2ctd wrote on February 24, 2023 at 10:33 AM

While it is true that it is rare to "sense" kidney function decline, it is a trivial matter to detect with blood and urine tests. If you get a blood test every year as part of routine screening, you will catch kidney disease as soon as it begins.

[deleted] t1_j9ukuiy wrote on February 24, 2023 at 5:47 PM

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wannabe-physiologist t1_j9tkqe3 wrote on February 24, 2023 at 1:45 PM

Unilateral kidney failure is possible in cases of unilateral nephrolithiasis (kidney stones) however this would be painful enough to prompt someone to go to the ED where the imaging and labs others have mentioned will be done.

In the case of unilateral nephrolithiasis you would expect to see a patient with unilateral flank pain, CVA tenderness, and the urine studies would show red blood cells in the urine. This isn’t technically kidney failure per se, but is one of the ways someone without access to care may develop it.