The Significance of Bacteria in Feline Cystitis and Urolithiasis

Abstract

SUMMARY A total of 48 male and female cats with signs of cystitis or urethral obstruction were evaluated. Other criteria of selection included (1) the lack of any complicating disease, (2) no previous catheterization or surgery of the urinary tract, and (3) no therapy for at least 1 month prior to presentation. Urinalyses were performed in 46 cats and confirmed the presence of an inflammatory urinary tract disease. The urine constituents were of a rather characteristic pattern, with many red blood cells, relatively few white blood cells, a high specific gravity, neutral pH, variable amounts of struvite crystals, and +2 to +4 proteinuria. Bacteria could not be demonstrated in gram-stained smears of the urine in 85% of the cases and bacteriologic cultures of urine collected by a midstream clean-catch technique yielded only insignificant growth (< 10 4 bacterial colonies/ml. of urine) in 12 cats and no growth in 35 cats. Only 1 specimen had significant bacteriuria (> 10 5 colonies/ml.); this sample was suspected of being contaminated because of failure to demonstrate organisms in gram-stained smears or sediment culture. This evidence indicates that the urolithiasis-cystitis syndrome in male cats, with and without urethral obstruction, and cystitis in female cats are not caused by bacterial infection. The urolithiasis syndrome in male cats resembled cystitis in female cats, the only apparent difference being the occurrence of urethral blockage in the male.