Benefits of urine testing include noninvasive collection and the wealth of information it generates from a single sample; "there's no single blood test that can give you the same number of results you would get from a simple urine test," said David Stein, PhD, CEO of Point-of-Care, Siemens Healthcare Diagnostics.
Today's dip-and-read strips can yield as many as 12 high-value results to give the clinician a fast snapshot of a patient's health, Dr. Stein said.
"This is especially valuable in areas of the world where you don't have a blood testing instrument, where you just need a quick assessment of how a patient is doing," he added.
A routine urine screening can show presence of blood, leukocytes, nitrite and protein, potentially signifying urinary tract infections (UTIs) or kidney disease. Siemens' newer point-of-care (POC) urine test strips offer checks for microalbuminuria, since small amounts of the protein albumin can leak into urine when kidneys are damaged. "We can accurately measure microalbumin to give an indication if a patient is in early- stage kidney disease so it can be managed to prevent long-term affects," Dr. Stein said.
The strips also provide ratios of creatinine-a chemical generated from muscle metabolism, which is important for adjusting the albumin value for varying urine concentrations.
Brian D. Miller, director, Scientific and Clinical Affairs, Iris Diagnostics, said urinalysis also helps point to nephrotic or nephritic syndromes, and high blood sugar or diabetes (via ketone and glucose levels). Blood testing is the preferred method for confirming diabetes since no urinary markers are approved for diagnosis/management of diabetes. However, urinalysis can be used as a front-line test.
Urine tests also indicate pregnancy via hCG.
To understand how the urine testing market has evolved over the last decade, Dr. Stein suggested breaking the market into the physician office laboratory (POL), decentralized areas of the hospital (e.g., emergency department [ED] and labor and delivery) and the central lab.
In the POL, testing has progressed from visual readings where technologists rely on color charts to assess results, to semi-automated, single-use, single-strip instruments where strips don't have to be removed and results print directly from the instrument. New features include operator and quality controls (QC) and electronic medical record (EMR) integration.
Many hospital departments have moved to full automation. Since a hospital may have as many as 60 remote analyzers with 1,000 operators, instruments can be tied to a data management solution to assure user authorization, validation, etc.
Miller said Iris is the only U.S. company providing images of urine samples via flow imaging technology on its automated iQ200 series urinalysis systems. As samples move through the analyzer, the instrument takes pictures and, using special software, groups them according to components before saving the images to the analyzer.
The images yield more information than a cell count, Miller said, and are helpful if a clinician (e.g., a nephrologist) wants verification that urine components were correctly identified. Further, "if you've done manual microscopy, you don't usually save the samples, so you have to go back and recollect. You're saving a lot of time by having the images stored on the system."
Today's fully automated, high-volume urinalysis platforms offer hands-free, walk-away capability by releasing results straight to the laboratory information system (LIS) so there's minimal intervention by the laboratory technologist. "We offer various platforms-with the fastest being iQ 200SPRINT with 101 samples per hour and iChem VELOCITY
at 240 per hour," Miller said.
The systems also provide a comprehensive view of samples, which is especially important for the central laboratory, where a technologist's interest extends beyond just chemistry results to individual urine components (e.g., red blood cells, white blood cells, bacteria, etc.).
"Typically what might happen in a hospital is in an ED, you get blood showing up or high nitrite, and a sample would then be sent to the central lab to determine what else is in the urine," Dr. Stein said. "The Siemens CLINITEK AUWi system provides urine chemistry and sediment results with minimal need to check results manually."
The latest data management solutions connect to LISs, EMRs and urine POC instruments. A good data management solution empowers managers to monitor staff members and devices from a centralized location.
"If you have 100 systems, even if you walk around non-stop every day, you can't make that work," Dr. Stein said.
Miller says the company's iWARE software provides real-time clinical validation on its analyzers, before samples are ever released to the LIS. "As an example, if you have an alkaline crystal that shows up but your pH is acidic, clinically that doesn't make sense, so you can have that as a flag," he said.
Other software capabilities enable rules customization; set parameters meeting College of American Pathologists, Clinical Laboratory Standards Institute and other international standards; perform audit trails to track use on a particular system and operators who have made changes to results, as well as upcoming expiration dates for lot numbers and reagents. "That's the top level of quality control that is currently requested," Miller said.
Test to Report
To get an idea of the pathway a urine test sample may take through a fully automated solution, Dr. Stein starts with a Siemens Clinitest hCG Test cassette to test for pregnancy. The cassette is placed on the automated CLINITEK Status+ Analyzer where automated checks look for interferences, etc. The analyzer is connected to the CLINITEK Status Connect System, which enables operator authorization, QC protocols and lockouts, etc. prior to reporting results. The system integrates directly to the RAPIDComm Data Management System (for manager oversight) in addition to the LIS and EMR to generate the report.
"It is a great solution, especially in the emergency room where you can get the traceability of quality control, where to send that hCG result instead of having to write it down and put it manually into the chart," Dr. Stein said.
Miller says faster test turn-around time is the biggest benefit of today's urinalysis systems to patients: "If you're in the emergency room, you can get your samples screened really quickly and find out whether it's a possible UTI, so they don't give you medicine unnecessarily. And it gets you out of the ER quicker. We've even found in some studies that because our turnaround time is so fast on an automated system, you get better turnaround times for other tests in the lab because the technologist isn't focusing on ours."
Jill Hoffman is on staff at ADVANCE.