Mystery Kidney issue

Buttercup, F, Age 4, 14lb Clinical signs: Creatinine levels spiked to 9.9mg/dL (we dont have baseline figure) before dropping to 1.9mg/dL on IV/antibiotics before rising to 4.4mg/dL off IV Duration: 10 days Hello, this is Buttercup, who has been relatively healthy during her four years in Washington, DC, until we discovered some rather troublesome kidney issues within the past 10 days. October 30 Buttercup has been regurgitating food periodically for years but on this day she repeatedly vomited and spit up her food. October 31 We took Buttercup to the vet and they prescribed gabapentin. Buttercup was concerned about being sedated over the next 48 hours, raising concerns her kidneys were not processing the drug November 2 Vet does blood test: creatinine levels very high (about 9.9mg/dL) Vet tells us to take her to the ER immediately. We take her to a VCA clinic in Fairfax, VA and they warn us that the prognosis is rather dire. Doctors say some signs point to chronic kidney issue while others point to an acute one She is placed on antibiotics, IV, lower doses of gabapentin and feeding tube Urine culture does not show signs of any illness. Red blood cell levels are normal. November 3 Her creatinine levels halved to ~5 mg/dL. I forgot the other kidney metric from the blood test (BUN?), which also improved considerably. The vet is happy with the improvement. Off feeding tube and eating very well. November 4 Creatinine levels halved again to about ~ 2.5 mg/dL. BUN levels also improved Continues to eat well, stays on IV and antibiotics November 5 Creatinine levels dropped to 1.9 mg/dL. BUN levels also improved. We took her home and she seemed to be doing pretty well on a daily antibiotic Zeniquin 25mg and appetite stimulant cerenia 8mg November 6 - 7 Seems to be doing okay drinking well, using bathroom but eating a little less Some meows sound a bit more uncomfortable than usual November 8 Take her back to the vet and creatinine levels have jumped to 4.4 mg/dL Vet encourages us to take her back to the ER but they do not really know what the issue is. Her appetite has slowed down a bit. She does not seem interested in her typical Royal Canin hard food but is eating a lot of delectable squeeze poaches and Temptation Treats. We still do not know what the issue is. Vets are guessing kidney stones or infection or chronic kidney issues Unfortunately, we do not have pet insurance and have paid over $8,500 at this point. We are happy to pay a little more but do not have a ton of income to spare, particularly if we do not think she will improve Other potential causes? I bought my partner Kenyan roses from grocery store and used the flower food pouch on October 27. We do not have a sense of whether she nibbled at the flowers. Our other cat appears fine. Buttercup has been grumpier the last year or so. She used to give warnings before nipping at people but she began nipping without warning on a daily basis, particularly when touched on her back. She has not nipped since returning from the hospital Our building occasionally sprays our apartment with insecticide but they assured us it was not harmful Our plan is to take her to the ER now. We are very worried about her. But we are also worried of spending endless money if she is not improving. What might Buttercup's issue be?

Hello - and thankyou for this complex question.  It is almost inevitable for kidney perameters to improve with a drip; indeed, it may be the fluids making a difference.  Good questions for your vet include:  what do you know about this case?  Can you be sure at this stage that there is a primary problem with the kidneys?   If not, are more tests needed?  If so, can you predict the likely cause and long-term outcome yet?  What more information would be useful? - and also, what are the costs (both in financial terms and to welfare) vs the benefits of finding this out / treatment? It sounds to be time to take stock of the situation and to make a plan going forward.   This is best done in consultation with the primary clinician in charge of the case.  Please never be shy to talk about money - money underpins every medical decision (in the UK this is hidden from human patients, so when it comes to feline health-care, we can be shy of discussing it). Another good line of questioning is 'What are the main things that could be causing this?'  and 'Which of these is likely to have a positive outcome?'   'What is the best case prognosis and worst case moving forward?' I hope that something there is useful, without my stepping on the vets' toes in this case.