Nothing Gold Can Stay: Rethinking UTI Testing Standards

By Timothy J. Mattimore, Jr.

In his famous 1923 poem, Robert Frost said, “So dawn goes down to day. Nothing gold can stay.” Such sentiment applies to medical testing standards, although it often takes a unique perspective to see when certain “gold” standards of medical testing lose their luster and must be replaced.

Peter Rising does not consider himself an inventor, scientist or expert in microbiology. Peter is a self-described “problem solver.” For over twenty years Peter ran a successful business designing and manufacturing water-testing kits for municipal water authorities and similar customers. When customers requested advanced testing functionality, Peter set to work on improvements to his products to give customers the performance they required. His development of specifically designed, vacuum-sealed ampoules as the primary test vessel enabled customers to test for various microbes and other contaminants in water more quickly and accurately than ever before.

A few years ago, a Canadian sales rep asked a question that would change everything. “Would your ampoule test work on urine?” Peter answered, “I’m sure it can.” This led him to analyze the urine culture market and the potential to adapt his water-testing technology to urine testing for the detection of urinary tract infections. What Peter found was a method of laboratory testing which had many problems that required solving:

•  The samples tested were unrepresentative. Despite medical and laboratory standards, which uniformly stated that samples should be tested within two hours of sample harvesting to ensure such samples were representative of the condition in the body, samples were routinely 8-24 hours old before testing was initiated. Such samples were also subject to inconsistent preservation, refrigeration and incubation practices. Because of these inconsistent sample custody practices and the fact that recordkeeping of samples in transport was nonexistent, the labs did not know the age or condition of samples when the samples were delivered for testing.

•  Testing took too long. Once testing began in the lab, the testing process on agar plates took at least 24 hours, and results were often not communicated to caregivers for 48-72 hours. This delay often forced doctors to recommend treatments, including the prescribing of antibiotics, well before such doctors received the lab results.

•  First-round results were inaccurate. Due to poor scientific testing processes, including a small sample size tested (1-10 microliters), the use of calibrated loops which were often not properly cleaned between samples and which only collected the surface liquid of a sample for testing, and the inability for tests to distinguish log phase (infectious) bacteria from lag phase (non-infectious) bacteria, first-round results were often inaccurate. Labs routinely experienced first-round false positive rates in excess of 30%, and labs had no way to determine their false negative rate.

•  Because testing and recordkeeping methods were manual and labor intensive, testing for POA infections and HAIs was impractical. As the need for hospitals to test for present-on-admission and hospital-acquired infections became critical with Medicare’s new policy on withholding reimbursement for treatment of hospital-acquired infections, hospitals could not turn to microbiology labs using agar plates to handle the additional volume. The labor and cost of performing plate tests on all potential POA and HAI cases was prohibitive for most facilities, and the manual recordkeeping associated with plate testing would only add to the strain of complying with new HAI reporting requirements.

Perhaps the biggest problem of all facing Peter and his newly-formed company, MicroBionetics, was the widespread belief in the microbiology and medical worlds that use of agar plates was an established standard that could not be significantly improved. The name given to agar plate testing—the Gold Standard—reflects how indoctrinated this view had become over time. Peter and his colleagues knew that many microbiologists would hold fast to the comfort of the Gold Standard and not risk the increased scrutiny inherent with adopting new technology, despite the Gold Standard’s many shortcomings and the need for hospitals to lower costs wherever possible.

It would, therefore, take a unique perspective, a unique product and a unique company to solve all the problems inherent with Gold Standard testing and overcome the natural reluctance for the market to move to a new methodology and standard. Not only must the product be technically superior to agar plates, it must be easy to validate, implement and operate in the laboratory setting. It must also significantly reduce costs and lead to better patient care.

MicroBionetics and its product, the CultureStat Rapid UTI Detection System, are up to the task. CultureStat is a true bacteria culture test that uses (1) a vacuum-sealed ampoule containing growth media and indicator and (2) a small, automated, multi-wavelength light spectrophotometer connected to a computer to detect and measure bacterial growth in a urine sample. The ampoule creates a protected, in situ environment in which log phase bacteria, if present in the sample, continue to reproduce and respirate. The light spectrophotometer (called the CultureStat Reader) measures the cell mass increase and respiration of the bacteria to produce results which are both rapid and accurate.

Let’s reexamine the Gold Standard problems presented above, and how CultureStat solves each problem:

•  Unrepresentative samples: Testing with CultureStat begins as soon as the ampoule is filled. If samples must be transported to the central laboratory, transporting the samples in CultureStat Ampoules ensures samples are representative because (1) the test begins at the collection site, as soon as the ampoule is filled, and (2) the sample is preserved and the bacteria nourished within the ampoule, meaning the sample stays representative through the transport process without chemical preservation.

•  Time of test: Because of the sensitivity of the CultureStat Reader, testing using CultureStat takes two hours or less, despite the fact that it is a true bacteria culture. Such speed allows caregivers to make treatment decisions based on actual test results, drastically improving patient care and reducing costs.

•  Accuracy of first-round results: CultureStat’s advanced scientific methodology—including testing a full 7 ml sample, using light spectrophotometry to objectively measure cell mass increase and respiration, and being able to distinguish between log and lag phase bacteria—eliminates false negatives and minimizes the potential for false positives. More true negatives are identified and removed from the testing process before a full C&S analysis, which means labs can operate more efficiently and microbiologists can spend more time on positive samples.

•  Practicality for POA and HAI testing: Operating CultureStat is as easy as clicking a button on a computer screen. The CultureStat Ampoule is placed in the CultureStat Reader, and the operator clicks a button to begin the spectrophotometric analysis of the sample. The CultureStat Database Software Program retrieves the data from the Reader and automatically determines and records all results. Patient identification information can be recorded using a bar code scanner. Because the entire test is run mechanically, human error is avoided. The hands-on testing process takes only 15-30 seconds per sample, including the recording of patient information and results (compared to 3-5 minutes for testing and recordkeeping under the Gold Standard). The speed, ease of use, and advanced data recording features of CultureStat make it the ideal test for all first-round samples in the lab. CultureStat is also the perfect solution for testing samples from admitted patients to determine present-on-admission and hospital-acquired infections. The automated data recording feature of CultureStat also makes compliance with new HAI reporting requirements extremely easy.

Most significantly, CultureStat does not stray from the basic microbiological principles of agar plate testing—namely allowing bacteria present in urine to continue to grow and measuring such growth. CultureStat is a true bacteria culture, but utilizes superior scientific methodology to produce faster, more accurate and more economical results than Gold Standard testing. Microbiologists can easily incorporate CultureStat into their labs, and can demonstrate the advanced performance of CultureStat to lab managers, doctors and hospital administrators with confidence.

Indeed, in the world of medical testing, nothing gold can stay. The Gold Standard has lost its luster, and labs, hospitals, caregivers and patients deserve a new, higher standard of UTI analysis. By converting to CultureStat, labs can quickly establish this new standard to the benefit of all.

The author can be contacted at tjmattimore@microbionetics.com.