Cystitis (bladder inflammation), Urethral Blockage, Bladder/Kidney Stones - Pt 3

A very important note on antibiotic usage in these cases: Most cases of cystitis are sterile. In other words, they are not the result of an infection and the patient should not be placed on antibiotics.

Only ~1% of cats with cystitis that are under 10 years of age have a urinary tract infection, yet many veterinarians place these patients on antibiotics when these drugs are not warranted. Most cats under 10 years of age produce a very concentrated urine (USG greater than 1.035) and bacteria do not grow well in concentrated urine.

In cats over 10 years of age, infections are more common but that still does not mean that older cats with cystitis should automatically be put on antibiotics. The reason that an older cat is more prone to urinary tract infections is because kidney disease is more common in this age group and so these cats will have a more dilute urine which is not as hostile to bacterial growth.

Diabetes and hyperthyroidism are also more common in cats over 10 years of age and both disease render the patient more prone to urinary tract infections.

That said, only ~20% - or less - of all older cats that present with lower urinary tract signs (see Feline Urinary Tract Health - Cystitis) actually have an infection so ~80% of this age group exhibiting these clinical signs do not need to be put on antibiotics.

A urine culture and sensitivity (C & S) should be run to check for an infection, especially if the patient has a low urine specific gravity or is diabetic. It must be kept in mind that even with a low USG, most cases of cystitis are not due to an infection. This is why it is important to run a C & S before placing the patient on antibiotics.

Antibiotics are NOT harmless drugs and they need to be used with more critical thought than is currently happening in both human and veterinary medicine.

This is especially true of Convenia. Please do not allow that drug to be injected into your cat without reading my Convenia webpage first.

A C & S test identifies the bacteria (if present) and tells the veterinarian which antibiotic is appropriate. The urine for a C & S needs to be obtained by way of cystocentesis which involves using a syringe and needle to obtain urine directly from the bladder.

This is not a painful procedure for the cat and this method is the only way to obtain a sample for accurate information in order to properly treat with antibiotics. One problem, however, is that a sample may be difficult to obtain without waiting a couple of hours since cats with cystitis urinate frequently and often do not have enough urine in their bladder to get a good sample.

To get around this problem, your veterinarian can give the your cat a dose of subcutaneous (just under the skin) fluids. The patient is then put into a cage without a litter box. Within a couple of hours (or less), the bladder is usually full enough to obtain a urine sample via cystocentesis.

We have to stop treating all cases of cystitis with antibiotics without supporting evidence of an infection!

Cystitis will often recur in these patients and this painful health problem can be very frustrating to deal with. On a good note, most cats will have their clinical signs spontaneously resolve even without any treatment. In fact, it has often been said, jokingly, that a cat with cystitis will often stop exhibiting clinical signs within seven days with antibiotics and in one week without antibiotics.

Unfortunately, when people don’t understand this issue, antibiotics often get the credit when they had nothing to do with the patient’s improvement. When this happens, the abuse of antibiotics continues.

Inflammatory Bowel Disease (IBD): IBD can cause vomiting, diarrhea, and/or constipation in the cat. IBD can also present with weight loss as the only clinical sign. There are many unanswered questions with respect to this disease process, but it is logical to start to “treat” a gastrointestinal issue with diet