I am afraid that it is impossible to give a single diagnosis for her condition without having a look at her and performing a physical examination (and neurological examination). This i because she is showing signs that are associated with a number of conditions in a cat her age.
Weakness that causes wobbliness (ataxia) can arise or a range of reasons. If we overlook this being caused by her being ill with an bacterial or viral condition, we still have to consider a range of metabolic (hyperthyroidism
) and organ (ie kidney
,heart, or liver) diseases. And it worth noting that all of these would lead her to lose weight and have an increased thirst before causing weakness and leading to her going off her back legs.
Also, while it isn't nice to think about, we do have to consider that cancer can cause the signs you are seeing with your wee kitty and must be on our list of diseases that would lead a cat to wobbly weakness and collapse.
As well, if there is pain involved, then I would be concerned that we cannot rule out that she may have throw a blood clot (which can lead to loss of leg control and extreme pain). That said, full clot obstructions can lead to complete paralysis and the feet do become chilled with time (because of the loss of blood flow). So, it may be a partial clot to blame. Furthermore, we do have to consider that this pain may be a problem in itself (ie spinal arthritis) and the weakness one of the above mentioned issues.
So, it is not possible to narrow your cat 's situation one disease entity. That said, all of the diseases I have outlined above are quite serious and need to be addressed. While it would normally be ideal to rule these out with a blood or urine sample, I am very concerned about this pain element you are describing. Therefore, even before ruling out the underlying chronic disease that has been eating away at her, I think you need to have her evaluated to make sure there isn't a painful clot present. If there is, she will need to be hospitalized (put on pain relief, and supportive care) but she will have a guarded prognosis. Therefore, with this pain element, Shiela really does need to be see as soon as possible. If this can be ruled out, then pain needs to be addressed and the other potential causes for her wasting must be addressed.
I hope this information is helpful.
Please do let me know if you have any further questions.
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