In humans, semen contamination has been shown to alter measured urine protein concentrations. In 1 study,1 for instance, postcoital urine samples from 6 of 22 men had some degree of proteinuria, as determined by means of dipstick analysis, even though results of dipstick analysis of precoital samples from all of the men were negative for protein. In another study,2 clinically relevant protein concentrations were found in initial-stream, but not midstream, morning urine samples from men who had had intercourse the previous evening, and in a separate study,3 protein concentrations of postcoital urine samples in which spermatozoa were detected ranged from 100 to > 300 mg/dL, even though precoital urine samples were negative for protein. Finally, the addition of WE or spermatozoa-free SF to urine has been shown to result in proteinuria.3
To our knowledge, there are no published reports of the effects of semen contamination on urine protein concentration in dogs. The purpose of the study reported here, therefore, was to determine the effect of semen in urine specimens on urine protein concentration measured by means of dipstick analysis.
Bayer Multistix, Siemens Clinical Diagnostics, Elmhurst, Ill.
Olympus AU640e automated analyzer, Melville, NY.
Pinnacle 530 pH meter, Corning Inc Life Sciences, Lowell, Mass.
Probe (No. 476346), Corning Inc Life Sciences, Lowell, Mass.
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