Why is my cat meowing when looking at his water bowl and in the litter box?

[debodun]

My almost 18-year-old neutered male cat is suddenly meowing (not a gentle mew, but a howling meow) when he approaches his water bowl and while he's drinking. He also howls when in the litter box and keeps one back paw on the top edge. Last July, my vet said he was starting to have kidney failure. Could this behavior be related?

[opus88]

Yes it could be, but more likely has crystals in his bladder which can block off the flow of urine, this is extremely painful as well as a medical emergency....his bladder can burst please get him to a Vet clinic ASAP