What is your diagnosis? THE ANSWERS… 1. What are the radiographic findings?
There is good serosal detail. The bladder silhouette contains extensive radiolucent/gas opaque streaks and pockets, both within the lumen and conforming to the bladder wall (Figure 2). The prostate gland is moderately enlarged. There is mild ventral vertebral spondylosis deformans noted at L6/L7 and L7/S1.
2. What is the radiographic diagnosis?
The appearance of the urinary bladder is consistent with a diagnosis of emphysematous cystitis. The prostatomegaly in an entire male dog most likely represents benign prostatic hyperplasia, however concurrent prostatic inflammation/infection (i.e. prostatitis) cannot be excluded.
3. What would be the next diagnostic step?
Not all cases of emphysematous cystitis are readily identified from radiographs, particularly if only a small amount of intramural gas is present, or if the bladder is superimposed by intestinal loops. Abdominal ultrasound has therefore been suggested as a more sensitive means for detecting emphysematous changes in the bladder (Petite et al. 2006), and whilst it was not necessary for the diagnosis in this case, the patient was referred for a specialist abdominal ultrasound to look for an underlying cause. The ultrasound revealed a highly abnormal urinary bladder with large amounts of both intraluminal and intramural gas which cast hazy distal acoustic shadows (Figure 3), consistent with severe emphysematous cystitis. Visualisation of the bladder lumen and far wall was hindered by the distal acoustic shadowing artefact, however, the far wall of the bladder had the impression of moderate to severe diffuse
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Figure 2. The same right lateral abdominal radiograph as in Figure 1. Note the extensive gas streaks and pockets within the bladder lumen and bladder wall (white arrows), and the enlarged prostate gland (red circle).
thickening. Multifocal collections of free peritoneal gas were also identified within the caudal abdomen, likely due to translocation of gas across the bladder wall, however, there was no evidence of free peritoneal fluid. The prostate gland was moderately enlarged with smooth capsular contours and symmetrical lobes, however, there were multiple irregularly shaped and poorly demarcated hypoechoic regions within the parenchyma. The appearance of the prostate was most suspicious for benign prostatic hyperplasia with concurrent prostatitis, although an underlying malignancy could not be entirely excluded without tissue sampling.
The liver was also moderately diffusely enlarged with an increase in parenchymal echogenicity and coarsening of echotexture. This hepatopathy/hepatomegaly was the likely cause of the increased ALP found on biochemistry. As a non-specific finding, causes are varied but include vacuolar hepatopathy, hepatitis, cholangiohepatitis, infiltrative neoplasia or nodular regeneration, and tissue sampling would be required for a definitive diagnosis.
Discussion
Emphysematous cystitis (EC) is a form of complicated urinary tract infection, defined by the presence of gas within the bladder wall and lumen (Fumeo
Companion Quarterly: Official Newsletter of the Companion Animal Veterinarians Branch of the NZVA | Volume 32 No 3 | September 2021
