Cat is sick, vets don’t know what’s wrong

Background: This is about Gustav. Gustav is 1/4 bengal and is an absolute weirdo, I’ve never known a cat like him. He is about 7 years old and is a very slim and energetic, playful cat. He has always been healthy, never had any problems apart from when he’d lose a fight which was the end of the world for him. Gustav hates shut doors and the fact he’s not allowed on the kitchen sides to eat all of the (people) food. The most random food he likes is jacket potato. We have another cat named stink who is about 11. They are both neutered and seem to get on. They’ve both been with us since they were kittens.

At the weekend (Saturday) he was as crazy as normal and trying to eat everyone’s food. All in all he appeared absolutely fine, if not a little sad as he wasn’t allowed any beef pie. I gave him about 4 dreamies (cat treats) at lunch time and that is the last thing he has eaten.

Sunday he didn’t touch his food, he is known to be very fussy so we weren’t overly concerned, he still seemed okay.

Monday (bank holiday) my mum was getting concerned as he still wouldn’t eat. He was offered everyone of his favourite foods and still wouldn’t eat. He licked a piece of ham and that was it. He has a cat fountain which is also used by stink. I saw him drink from it twice so I know he had some water.

Tuesday my mum rang the vets and he was seen in the morning. Physical examination found nothing other than he had lost around a 1KG since he was last seen about 4 months ago and his anal glands were full (but not blocked) and there was blood on the thermometer after taking his temperature. The vet drained his anal glands, gave him an injection with something to stop any pain and sent him home with some probiotics. They asked to see him the next day if he was no better.

Wednesday (today) he was no better at all and seemed like a shell of his normal self, he doesn’t play. He just walks around or sleeps. If he’s stroked he does purr and let you stroke him and he doesn’t appear to be in any pain. He still hasn’t eaten anything and wouldn’t have the probiotic anywhere near him, let alone in his mouth. My mum took him back to the vets this morning. They examined him again and again found nothing physically wrong, but he had lost weight since the day before. They took some bloods and sent him home and they’d ring later on to let us know what they found. They rang at about 4pm (now 6pm). Nothing obvious was found in his blood results but they wanted to see him again. My mum took him back and he was again examined and they again found nothing. The vet said the only thing they found in his blood were that his albumin levels were low. Which could apparently point to something wrong with his liver. The vet also said he was extremely dehydrated.

He is on his way to be admitted to the vet hospital now so that he can be put on a drip. Once he is rehydrated they plan to do more blood tests to confirm the results and then do an ultrasound to see if they can find out what is wrong. The original vet said it could be his liver due to the low albumin but she can’t confirm anything.

I just wanted to know if anyone has experienced this before or if anyone has any ideas of what could be wrong?