My senior cat with CKD is losing weight. Is immune decline next?

It sounds like you and you vet have a good plan for your kitty. Depending on any symptoms other than weight loss and his most recent blood work, adding on a phosphate binder and antacid may help. The antacid would be helpful if his appetite is low. If he has high blood pressure, then medications for that may be needed, especially if your vet suspects it could be leading to protein loss in the urine (a cause for weight loss in cats with CKD).

Renal failure often causes cats to lose weight. The waste products that build up in the blood because the kidneys can't properly eliminate them cause nausea and gastritis (inflammation in the stomach) and sometimes even ulcers in the mouth. Talk to your vet about trying some medications to manage these conditions - either omeprazole or famotadine are often helpful, as well as the anti-nausea drug Cerenia. Also the drug mirtazipine can be used to help stimulate his appetite. Unfortunately it sounds like he has multiple problems that may be difficult to manage concurrently. I'd also consider running a bacterial culture of the nasal discharge to try to focus the antibiotic therapy and ensure that an effective drug is being used.

Cats that are losing protein through their kidneys can lose weight. With your cat's medical history, I would recommend having him examined by the vet. Blood work will check the kidneys and urinalysis will look for extra protein in the urine. The blood work can also screen for other issues that can cause weight loss.

I'm sorry to hear that Puss hasn't been feeling well. His further weight loss with decreasing muscle mass could be related to progression of kidney disease, or could be associated with other conditions such as hyperthyroidism, cancer, inflammatory bowel disease, among others. Diarrhea is not commonly associated with kidney problems, however, and could be due to other gastrointestinal issues from diet changes, parasites, inflammatory bowel disease, cancer, or other problems. Regardless, it sounds as though another trip to the vet is in order to recheck his kidney values on blood testing, as well as additional diagnostic testing to try to determine the cause of diarrhea. From there, your vet will be able to come up with the best treatment plan possible to help Puss maintain as good of a quality of life as possible. I hope this helps and that all goes well.

There are a number of causes of weight loss in cats. I'm assuming that the information of 1 kidney being larger than the other was something that the vet noted when the belly was palpated on exam. That finding, in and of itself, doesn't necessarily mean the kidneys are the issue. I see that Neko is only 3 years old. Weight loss in a younger cat could be due to kidney failure, though its much more common in senior cats. Working only off of the information that Neko is a young cat who losing weight and has 1 kidney larger than the other, with no other history given, it is hard for us to get any impression for what may be wrong. Again, if she were a senior cat I would suspect kidney failure, and I would then recommend a canned prescription kidney diet, lots of water, TLC, and know that time is limited -- with the understanding that we don't KNOW its the kidneys without blood work. However, since Neko is young, its harder to jump to this sort of advice. It could be her kidneys, but other concerns would include inflammatory bowel disease, intestinal worms, or even something like FIP (feline infectious peritonitis). Some causes are relatively inexpensive to treat, and others are much more difficult. Additional information about any other signs would help us-- is she vomiting, how is her appetite, is she playful and active or is she dumpy and lethargic, is she hiding, etc. Please feel free to resubmit a question on the forum (no charge), or request a consultation (for a fee) and we can give information back and forth and would likely be able to assist you further that way. Thank you for asking Petco Pet Education Center, formerly Petcoach.

Adding in the wet food while providing her regular dry diet available as much as she wants should help increase her calorie count some. It is common for cats to start to lose weight as they age as their nutritional needs tend to change when they hit their senior years, plus absorption of nutrients overall tends to decrease with age as well. Mixing the wet into the dry may encourage her to eat a bit more and increase calorie count which should help. Your vet can also monitor her weight/BCS (most vets will let you weigh your pets at no charge) to make sure she is gaining/maintaining a healthier weight with the changes.

I recommend to have her examined. Certainly something like cancer is possible but there are some other conditions that are common in older cats like renal disease and hyperthyroidism that generally respond very nicely to treatment but this does depend on the severity. If renal disease is caught before things get too bad, cats require a special diet, sometimes a medication, sometimes subcutaneous fluids and the average time of quality life after diagnosis is 2 years. https://www.petcoach.co/article/how-to-care-for-a-cat-with-kidney-disease/ Hyperthyroidism can be controlled with a special diet, with medications or with a permanent solution like radioactive iodine treatment. Many cats with this condition will live normal live expediencies as long as they are medicated. https://www.petcoach.co/article/hyperthyroidism-in-cats/ It's always best to know whats happening. That way you can made an educated decision and prevent any suffering. Bloodwork and a urinanalysis will give you and the doctor a good idea of what is happening inside Natasha's body and then you can make an appropriate decision once you know what your options are. I recommend to get this done within the next day or two since both of these conditions will respond best to earlier intervention. I hope this helps.