APIM243887241 - CME/CMLE - Utilizing Molecular Testing Correctly-APIM243887241

APIM243887241 - Educational Activity

Pdf Summary

This educational commentary by Celesta Gibbs, M.S., MB(ASCP)CM, discusses the appropriate utilization of molecular testing in infectious disease diagnosis, emphasizing syndromic molecular panels and PCR methods. Molecular tests detect microorganisms by targeting nucleic acids (DNA, RNA), providing rapid, sensitive, and specific identification that surpasses traditional culture and antigen-based methods, especially for difficult-to-culture pathogens.<br /><br />Syndromic panels use multiplex real-time PCR to simultaneously detect multiple pathogens and antimicrobial resistance genes relevant to an infection syndrome, thereby improving diagnostic speed and accuracy. Common panels target respiratory, gastrointestinal (GI), blood, and central nervous system infections. For example, respiratory panels distinguish bacterial from viral infections to guide antimicrobial stewardship, often reducing result turnaround from about 16 hours to 3.3 hours, thereby optimizing treatment and reducing unnecessary antibiotic use.<br /><br />GI panels identify diverse causative agents of foodborne illness, including viruses like norovirus, which were previously difficult to detect. Blood panels rapidly identify bloodstream infection pathogens and resistance markers directly from positive blood cultures, decreasing time to diagnosis by up to 24 hours and improving patient outcomes. Meningitis/encephalitis panels enable rapid detection of CNS infections, though they don’t cover all possible pathogens due to clinical variability and cost considerations.<br /><br />Multiplex real-time PCR uses fluorescent probes with distinct fluorophores to detect multiple targets simultaneously, allowing high-throughput testing with excellent sensitivity and specificity. However, molecular tests detect both live and dead organisms, so they are not suitable for confirming cure.<br /><br />While multiplex panels often have higher upfront costs, they significantly reduce overall healthcare costs by shortening hospital stays, enabling targeted therapy, and limiting unnecessary antimicrobial use. As technology advances and costs decline, incorporating syndromic molecular panels into routine clinical microbiology holds promise for enhancing patient care and antimicrobial stewardship.

Keywords

Molecular testing

Infectious disease diagnosis

Syndromic molecular panels

PCR methods

Multiplex real-time PCR

Antimicrobial resistance genes

Respiratory infection panels

Gastrointestinal infection panels

Bloodstream infection detection

Meningitis/encephalitis panels