I would assume so yes, since the kidneys lie around the area just behind the saddle. Soreness in that area can be provoked by a couple of things; one being a saddle thats too long and puts pressure on the area.
Soooo if pressure there can cause general soreness id assume that a kidney infection certainly would.
I know ive had them (although im obviously not a horse
), and theyve caused me lower back pain - really a rather short nasty pain also.
He was generally sensitive around the abdomen and lower back area, got to the point where he would kick out if you touched it (and he had never kicked before)
If you suspect it might be, please get him looked at straight away as can be really serious, we didnt think J was going to make it, but once they worked out what it was and treated it he gradually improved.
Somebody suggesed to me about a kidney infection causing his erratic jumping beaviour (i.e. launching me out of the front door over every fence!) so i was goin to speak to the vets on monday and hopefully run a urine sample up to them.
He had some sensitivity just infront of his point of hips either side of his spine (if that makes sense) so I thought I'd better check.