How PCR Revolutionizes Diagnostic Speed and Accuracy in Healthcare

In the world of patient care, change is the only constant. The need to provide patients with faster diagnostic results while maintaining accuracy drives the healthcare industry forward to continuously innovate. In the modern day, if you were to develop a new diagnostic tool for pathogen detection that took 3-5 days to result, you’d have a hard time getting a patient to sign onto using it!

Perhaps that’s because a technique like that already exists - in the form of bacterial and cell culture. The time to result of classic culture techniques has hampered health systems, labs, providers, and patients themselves in their ability to treat or be treated for infections in a way that is rapid and targeted. The increased use of Polymerase Chain Reaction (PCR) testing stands as a testament to the fact that modern healthcare has had enough of waiting.

There are a number of ways PCR outshines culture, with ongoing improvements to the technique that make it a progressively more compelling option for physician’s practices. Because of this, PCR has the power to reshape diagnostics and, thus, offer patients a quantum leap forward in time-to-result, clinical accuracy, and sensitivity. 

The Efficiency Leap of PCR

Traditionally, culturing methods have been the de facto choice for pathogen identification. PCR takes a different approach by amplifying genetic material, a process which can be shortened from the 3-5 days that it normally takes with culture to just hours. So drastic is the shortened diagnostic timeframe that many physicians leverage this to choose tailored antibiotics before a patient even leaves the office! PCR’s ability to drastically reduce time-to-diagnosis in this way is renowned - it’s the main reason PCR was used when speedy response times were demanded by the COVID-19 pandemic.

Improving on Sensitivity and Specificity

Of course, speed is important, but so is accuracy. A recent study in the journal Urology demonstrated a high level of ​​agreement between PCR and urine cultures for positive cultures (90%), clearly exceeding non-inferiority thresholds (85%).¹ Further, since PCR does not rely on live organisms, it may have some usefulness in situations where antibiotics have already been administered, such as in meningitis patients.² Inherent to PCR is its ability to detect pathogens even in low concentrations, which can translate to a heightened sensitivity.  

The Added Advantage of Antibiotic Resistance Marker Detection

Considering the prevalence of antibiotic resistance among patients, there is an increased demand to leverage modern techniques in the fight for antibiotic stewardship. While cultures can provide antibiotic sensitivities, they cannot detect the presence of antibiotic resistance markers. PCR can not only identify organisms, but also the presence of these critical resistance markers, which allows providers to more judiciously prescribe laser-targeted antibiotics.

Benefits for Laboratories

PCR has firmly established itself as a diagnostic tool that can provide physicians with increased speed, clinical accuracy, and sensitivity when compared to using cultures. It also has the unique ability to detect antibiotic resistance markers to help doctors make better decisions as they fight the new pandemic of antibiotic-resistant organisms, and is continually being improved as a diagnostic platform. When change is the only constant, and classic techniques no longer meet the needs of modern providers, they can be confident that PCR will help them face the future and provide the best outcomes for their patients.

References

1. Wojno K, Baunoch D, Luke N et al. Multiplex PCR Based Urinary Tract Infection (UTI) Analysis Compared to Traditional Urine Culture in Identifying Significant Pathogens in Symptomatic Patients. Urology. 2020;136:119-126. doi:10.1016/j.urology.2019.10.018
2. Bryant PA, Li HY, Zaia A, et al. Prospective study of a real-time PCR that is highly sensitive, specific, and clinically useful for diagnosis of meningococcal disease in children. J Clin Microbiol. 2004;42(7):2919-2925. doi:10.1128/JCM.42.7.2919-2925.2004