A urinalysis is an important diagnostic tool used to identify medical problems with the kidneys and genito urinary system. Performed in both the inpatient and outpatient setting, a urinalysis is a simple test that yields quick results. Although a urinalysis typically provides data for many substances found within urine, the presence of protein is often an indicator of medical problems within the renal or urinary system.
Urinalysis
Analysis of a urine sample can often provide important information regarding the current health of a patient. In many cases, patients are asked to provide a urine sample by urinating into a collection cup provided by the clinic or hospital. The cup is then sent to a laboratory that determines what substances and compounds are contained within the urine. The amounts of various substances found within the urine can help identify the presence of renal or genitourinary disease.
Renal Failure
The kidneys are responsible for the regulation of fluid and electrolytes within the body. In addition, the kidneys also filter out toxins and metabolic products for excretion. In some instances, the kidneys also reabsorb certain biological compounds. During healthy renal function, the kidneys retain or reabsorb proteins after filtration. However, in the presence of kidney disease, protein leakage and impaired re-absorption can cause excessive amounts of protein to be found within the urine. Albumin and other proteins that are important components of blood and plasma are the proteins most commonly found.
Urinary Tract Infection
According to a review published in 2006 in "Nephrology Dialysis Transplantation," Joanne L. Carter and colleagues examined the association between proteinuria and urinary tract infections. The article suggested that there was a strong correlation between symptomatic urinary tract infections and the presence of excessive protein within the urine. Although the nature of this correlation has not been conclusively determined, the article speculates that the source of protein may stem from increased amounts of blood that can be found in the urine during a urinary tract infection.
Contamination
An additional source of protein in the urine can be from contamination during the sample-collection process. Since the patient often self-collects a sample by urinating into a cup, there is some potential for contamination. Although less likely, a urine sample may also be contaminated during the analysis process within the medical laboratory. Appropriate instructions should be provided to the patient about urine sample collection to avoid this problem. Patients should speak to a physician with concerns regarding the results of a urinalysis.
References
- "Nephrology Dialysis Transplantation"; Does Urinary Tract Infection Cause Proteinuria or Microalbuminuria? A Systematic Review; Joanne L. Carte, et al; July 2006.
- National Kidney and Urologic Diseases Information Clearinghouse: Proteinuria
- MayoClinic.com: Urinalysis
- Lab Tests Online: Urine Protein and Urine Protein to Creatinine Ratio
