Case Study

Polypoid bladder wall changes in a 9 year old FS Welsh Corgi

A 9-year-old spayed female Welsh Corgi dog was presented for evaluation for recurrent hematuria. On urinalysis, inappropriate SG (1.020) and proteinuria were present. Urine culture revealed Acinetobacter, Pseudomonas, and Enterobacter; the latter two were antibiotic resistant strains.

DX

Polypoid cystitis

Sonographic Differential Diagnosis

Chronic cystitis bladder pattern. There is a mild potential for underlying transitional cell carcinoma.

Image Interpretation

The urinary bladder presented dependent debris, polypoid bladder wall changes, and echogenic remodeling. The bladder wall changes appeared to be occupying 2/3 of the cranial bladder. The pelvic urethra was slightly thickened. No obvious neoplasia was noted.

Comments

A cystoscopy, along with anaerobic and aerobic cultures, would be ideal in this patient. Urinary bladder resection could be justified given that the chronic changes in the bladder wall would suggest that it would be difficult to completely clear the urinary tract infection with medical therapy in this patient. Embedded bacteria within the wall is likely an issue regarding recurrence. Inspection of the vaginal vestibule for urine pooling and/or recessed vulva would also be warranted to rule out underlying occult incontinence. Aggressive antibiotic therapy is recommended with once daily dosing in the evening after micturition to maximize urinary bladder concentration. Six weeks of marbofloxacin/tetracycline combination therapy could be considered. Recheck culture at 4 weeks and recheck sonogram at 6 weeks would be recommended prior to stopping any antibiotics. Pulse antibiotics may be necessary in this patient long term for management.

Clinical Differential Diagnosis

Bladder pathology – chronic bacterial cystitis, neoplasia, uroliths, polyploid cystitis, granulomatous cystitis. Renal pathology – pyelonephritis, renoliths, neoplasia.