Best practices of nucleic acid amplification tests

american society for microbiology

Best practices of nucleic acid amplification tests for the diagnosis of Clostridioides (Clostridium) difficile

The American Society for Microbiology’s Clinical Microbiology Reviews recently published a systematic review co-authored by Division of Laboratory Systems (DLS) Medical Officer Dr. Nancy Cornish. The study emphasizes the issues related to the diagnosis of C. difficile infection, with a focus on testing algorithms that include nucleic acid amplification tests (NAAT).

Using DLS’ Laboratory Medicine Best Practices (LMBP) A-6 cycle, the systematic review team concluded that the published evidence supports the use of testing algorithms that use NAAT alone or in combination with glutamate dehydrogenase (GDH) or GDH plus toxin enzyme immunoassays (EIAs) to detect C. difficile in adults.

The study also highlighted important gaps in the literature, including the lack of documented pre-analytic variables that affect diagnostic accuracy, such as consistency of stools and use of laxatives. Also among the gaps identified is whether the algorithms used in the clinical microbiology laboratory improved patient outcomes.