Originally Posted by
Dennis Thomas, DVM
Hi. I thought I might offer some information about UTIs in dogs. You didn't mention your Labs age and that would certainly be a consideration when trying to ascertain the source of the problem. When we think of UTIs in dogs, we usually think of a bacterial cystitis (bladder infection) as it is by far the most common problem of the lower urinary tract. However, if you look at dogs that have UTIs, then, by far, most of them are females. Why? Because they have very short urethras and it is very common for contaminant bacteria from the vulva area to migrate upwards into the bladder. Same goes for humans. It is very, very rare for a male dog to have a primary bacterial cystitis. Why? Because their urethra is very long and any bacteria around the prepuce that attempted to migrate upstream into the bladder would get flushed out each time he urinated. Then, how can a male dog end up with a UTI? Because the bacteria are secondary to another problem. In intact males, it is almost always associated with the prostate. In neutered males it could be secondary to crystals, stones, bladder tumors, infections coming from upstream (kidney infection, infections in the blood that originated from bad teeth, anal sac infections and others). The point that I am trying to make is the wise vet knows that primary UTIs in males is very rare and should be focusing on the underlying problem. It starts with the urinalysis (urine ph, crystals, USG, etc) and then moving from there. Keep this in mind as you move forward. The antibiotics will likely take care of the symptoms, but if they return, they need to find the source of the problem. Good luck.