Bacterial infection of the bladder is what causes bacterial cystitis in dogs and due to the shorter distance the bacteria needs to travel up the urethra to the bladder this disease is more common amongst females.
In most cases, the main source of bacteria will be the anus.
The relatively shorter distance between the vagina and the anus results in females being effected more so than males.
After reaching the bladder the unwanted bacterium will travel to the thin outer wall of the muscle that forms the bladder worsening the infection.
Trying to maintain a healthy body, at this point the mild acids in the dog's urine will try and fight the bacterium to stop the infection.
The infection will begin to worsen once this natural defense system fails and the acids in the urine run out.
A worsening infection would mean that the dog would feel a burning sensation in its bladder which in turn may rupture microscopic blood vessels leaking them into the urine and giving it a reddish pink color.
The natural response of the dogs' body would be to contract its bladder muscles and thus leave the bladder in a continuous state of spasm.
In this state, the dogs' bladder will create a feeling which would make the dog want to urinate and a similar feeling will be caused by the small amounts of urine filling up the contracted bladder.
What a Professional May Have to Say.
If the vet suspects the dog to have bacterial cystitis they will ask you to bring in a urine sample which will be used to test for acidic (pH) levels, glucose and blood cells.
If the vet manages to find blood vessels in the urine sample this will confirm that there is inflammation of the bladder and thus the proper diagnosis will lead to appropriate treatments to cure the disease.
If there is glucose present in the urine, which encourages bacteria growth, it might mean that the dog has a mild case of diabetes and a different treatment would be suggested to cure cystitis.
The urine sample will also be tested for pH levels and if these turn out to be too high it will indicate that the dogs' urine does not contain adequate levels of acid to fight the bacteria which would make the dog more prone to this disease and will require further treatment such as a different diet to lower the pH level.
The vet may also want to conduct further tests such as an ultrasound scan, an x-ray or endoscopy to view the bladder.
These tests will help check the presence of abnormal cells such as tumors or microscopic bladder stones (crystals).
Only after all these tests and procedures have been conducted will the vet be able to diagnose the disease properly and suggest the appropriate treatment or inflammatory medicine to use.