The integrity of the urine sample is affected by many common contaminants, including:
- Menstrual blood
- Microorganisms (eg, yeast and bacteria from non-sterile collection technique)
Female patients should be instructed to not collect urine samples during their menstrual period, and to take precautions when collecting a urine sample during a bowel movement. Certain components, such as albumin, are in far higher concentrations in the blood than in urine. Albumin is widely used to assess the onset of kidney damage in patients with diabetes, and albumin from contaminating blood will falsely increase the measured levels in the urine, and may lead to misdiagnosis and inappropriate treatments.
Regardless of gender, the use of an antiseptic towelette is recommended to minimize the effects of contaminating microorganisms from the genitalia.