Case Study

Prostatic abscess, drained with ultrasound guidance, in a 11 year old MN Bichon Frise

An 11-year-old MN Bichon Frise was presented for persistent hematuria despite treatment with antibiotics. The dog had a previous history of prostatic carcinoma diagnosed 1 year prior that had been treated with misosprostal and piroxicam. On physical examination the prostate was unchanged in size since the last visit and the rest of the abdomen was within normal limits.

DX

Prostatic abscess

Sonographic Differential Diagnosis

Prostatic abscess within prostatic carcinoma.

Image Interpretation

The urinary bladder presented some debris and minor wall thickening. However, the pelvic urethra was impinged upon by a prostatic mass, which was more progressively mineralized with a 2 x 1 cm abscess in the middle of the prostate. This abscess was drained, and 7 cc of hemorrhagic flocculent fluid was obtained. Enrofloxacin was injected back into the abscess. This procedure reduced the volume of the prostate by 20%.

Outcome

The patient was recommended for treatment with enrofolaxacin and Cox-2 inhibitor therapy for 4 weeks, urine culture and sensitivity, and possibly switching medications to deracoxib. A recheck ultrasound was advised in 1 month to assess regression or progression of the prostatic pathology.

Comments

Patient was lost to follow up.

Clinical Differential Diagnosis

Persistent hematuria – prostatic disease (progressive neoplasia, prostatitis, abscess), bladder pathology (neoplasia, urolith).

Sampling

The prostatic abscess was drained via ultrasound guidance yielding 7 ccs of flocculent fluid. A single body weight dose of injectable enrofloxacin was infused into the cavity. Ultrasound-guided drainage and quinolone infusion has provided positive empirical results in both abscessing prostatic carcinomas and in prostatic abscesses (combined with neutering). We have found that clinical signs worsen with expansion of the cysts/abscesses within both neoplastic and benign prostates. It is easiest and convenient to inject antibiotics at the time of drainage. If there is suspected bacterial involvement based on fluid recovered, injecting baytril at the time of cyst drainage avoids the expense and risk of a second sedated procedure.