Limping, peeing in unusual places, weight loss, lethargic, weak

My Vet is stumped. Male feline,13 years old. Blood work not giving any indication of what's going on. Waiting on urinalysis results. Ultra sound showed no injury. Since urinalysis results can take 48+hrs, antibiotics were prescribed, in case it's a UTI. I also asked for pain meds. Was given a B12 shot. Temperature normal.

He goes from bed to bed and rests all day, gets up only to eat and use the litter box. He uses the litter box but peed on my bed twice. Sometimes he hides and his beds are under the chairs which are a bit hidden too. Since he did loose a pound, I'm bringing food to him to make sure he's eating enough, so he doesn't have to get up and walk. His appetite seemed okay since he was eating but not as much as usual, now he's eating more since I bring it to him. This all has been going on for 6 days now. His temperament is normal, purrs, sits on my lap but he is clearly not himself.

Has anyone had a similar situation happen? Where the blood work came back with no indication of disease which would cause limping and weakness. Since blood work can indicate kidney disease or diabetes I'm wondering if there's other test that should be done or if we're missing something???

Please note: Another incident of limping happened about 2 months ago, was his back leg (now it's the front), the vet (was an emergency visit so had a different Vet in their office on call) couldn't find anything wrong after examining him. Gave him a b12 shot. Took his blood pressure and of course, temp. Yet had no idea what could cause his limp. He got better after about 2 weeks. Now, 2 months later its happening again except, it's his front leg!!!

Has your baby been checked for arthritis?  

Sending prayers to your baby   .

Yes, I also wonder about arthritis. Has anyone done x-rays on him?

Thank you Tamu for the prayers and CatPack. Ultra sound only - actually he's had 4 ultra sounds within the last 2 months...had another one today. I just got back from another visit to the Vet. They aren't ruling out arthritis but since the frequency of his urinating, going in and out of the litter box and sometimes lying in the box, they think he may be diabetic since his blood work showed high glucose levels and the urinalysis came back today showing high glucose levels too. Dr. said if he took an x-ray that it most likely will show arthritis since as cats age (he said as we all age) arthritis develops but since there's so much else going on, he gave an insulin shot today and said to stay on the antibiotics. We will go back in Monday to check if the insulin shots (2 x a day) are working to lower his glucose. 

I feel so bad for my baby.

Ok, so new blood work IS showing elevated glucose AND there is now glucose in the urine? was this blood work done in house or sent to another lab? What was his glucose level?

Hopefully you will see improvement in the litter box accidents with the insulin.

And, while I do agree that arthritis accompanied age to some extent, some animals have a more serious problem with it and greatly benefit from treatment. (Laser therapy, glucosamine supplements, Adequan injections, pain management...) Just something to keep in mind as it does sound like your kitty could have several issues going on.

Thank you CatPack. The blood work was done 2 days ago before I wrote my first post, our Dr. thought the high level might be due to stress but since the urine showed it too they are now thinking maybe diabetes. The test was sent out to a lab for the blood and urinalysis. Blood showed 239 glucose. Urine showed 3+. They took a fresh urine sample today to check it as well (office checked it on the spot) it was "high" and they said the glucose level was 288 today in house. The Dr. does not know what is causing this limping and weakness. They are treating what they can and focused on the peeing issue. I will keep in mind the treatments you mentioned for arthritis...I'm not sure why these treatments were not discussed today. I noticed a laser pamphlet when I was at the office today and will look into the supplements. I am still giving him pain medication.