History & signalment
Tizzy is a 10y.o. FN Collie with a 4-month history of haematuria. The owner had noticed blood towards the end of the urinary stream on multiple occasions. Some blood clots had been identified in the urine. Some reduction in the frequency of haematuria was noted following treatment with antibiotics, but recurred following their cessation. Tizzy was somewhat lethargic but appetite and thirst were stable. Tizzy had been diagnosed as diabetic 2 years earlier and diabetic control was fairly good on twice daily lente insulin.
On clinical examination Tizzy was bright and alert and in overweight body condition. Mucous membranes were pink and moist. Thoracic auscultation was unremarkable. Abdominal palpation was also unremarkable with no signs of pain. Peripheral lymph nodes were not enlarged.
Haematology was unremarkable and platelet count was within normal limits. Clotting times were also unremarkable. Blood biochemistry initially revealed azotaemia, but urine SG was increased (urine SG 1.040), making a pre-renal cause more likely. Azotaemia had resolved by the next blood check and SDMA was measured which showed no evidence of kidney issues.
An abdominal ultrasound was performed, followed by some abdominal radiographs. Images of the urinary bladder are shown. Renal ultrasound was unremarkable.
Answer: Emphysematous cystitis
The ultrasound reveals an almost unrecognisable bladder. The wall is thickened and irregular. There were bright echoes and reverberation artefacts typically associated with gas and this had a static pattern regardless of whether the animal was standing or recumbent, indicating that the gas was entrapped in the bladder wall. The bladder contents were echogenic.
Answer: A cystocentesis sample should be collected for culture and sensitivity. In this case, culture was positive for a fairly resistant strain of E. coli.
Emphysematous cystitis is a rare condition in dogs caused by bacterial infection which results in accumulation of gas and cystic changes within the bladder wall. The gas is thought to be produced by bacteria, typically Gram negative bacteria such as E. coli or Klebsiella. Emphysematous cystitis is generally diagnosed in diabetic dogs and the most common isolate is E. coli, as in this case. Ultrasound is the most sensitive method to detect small amounts of gas in the bladder wall in early stages, but in this advanced case, radiographic changes were classical.
Answer: Bladder rupture and peritonitis are possible but most dogs will respond to appropriate antimicrobial therapy