November 2021 Case of the Month - Emphysematous Cystitis in an Intact Male Dog

Patient Information:

Age: 12 years

Sex: Male

Breed: Shiba Inu

History:

A 12 year old intact male Shiba Inu presented for ultrasound following a several month history of inappropriate urination as well as decreased appetite. Urinalysis showed glucosuria, though no hyperglycemia was reported.

Ultrasound Findings:

The bladder is moderately distended with anechoic urine and there is a moderate amount of gas within the superficial bladder lumen and bladder wall; however, the bladder is of relatively normal contour and thickness. Also noted are occasional uroliths measuring up to ~0.5 cm within the dependent bladder.

Interpretation:

Gas within the bladder wall and bladder lumen is consistent with emphysematous cystitis. This is a rare condition which is often associated with comorbidities such as impaired immune system (hyperadrenocorticism, long-term corticosteroid therapy, etc), cystolithiasis, neurologic bladder, chronic UTI, and diabetes mellitus. Interestingly, one study does not show any gender predisposition, though a more typical UTI would be expected to be found more frequently in females.

E. coli is the most common isolate in this condition, and is what was cultured from this patient’s urine. This bacteria ferments glucose and lactate into gases such as CO2, O2, and H2, which would explain the role of diabetes mellitus or other glycosuric conditions in the development of emphysematous cystitis. In the case of our patient, glucosuria was despite the absence of hyperglycemia. Glucosuria in the absence of hyperglycemia is suspicious for proximal renal tubular disease/injury. This may include Fanconi syndrome, jerky treat exposure, pyelonephritis, Leptospirosis, NSAIDs, or toxins.

Treatment:

The patient is currently being treated for his emphysemtous cystitis with enrofloxacin, and is responding well so far.

Reasonable workup of his glucosuria would include ruling out any exposure to jerky treats of any kind, then consider Leptospirosis testing and a Fanconi panel.

References:

Lippi I, Mannucci T, Santa DD, Barella G, Oranges M, Citi S. Emphysematous cystitis: Retrospective evaluation of predisposing factors and ultrasound features in 36 dogs and 2 cats. Can Vet J. 2019;60(5):514-518. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6463776/