What are the recommended diagnostic tests for Mycoplasma genitalium in a patient presenting with urethritis?

Recommended diagnostic tests for Mycoplasma genitalium in a patient presenting with urethritis primarily involve nucleic acid amplification tests (NAATs), which are the gold standard due to their high sensitivity and specificity. The UK guidelines (NG221) recommend testing urethral swabs or first-void urine samples using validated NAATs to detect M. genitalium DNA or RNA in symptomatic men presenting with urethritis ¹.

Recent literature supports this approach, emphasizing that NAATs remain the most reliable diagnostic method for M. genitalium, especially in resource-constrained settings where rapid and accurate diagnosis is critical (Wi et al., 2019). Advances in laboratory detection have improved the availability and accuracy of these molecular tests, including multiplex assays that can simultaneously detect M. genitalium along with other sexually transmitted infections (Waites et al., 2023).

Additionally, molecular testing can include assays that detect macrolide resistance mutations, which is increasingly important for guiding effective treatment due to rising antibiotic resistance (Raj et al., 2022; Waites et al., 2023). However, routine resistance testing may not yet be universally implemented in all UK settings but is recommended where available to optimize antimicrobial stewardship ¹.

In summary: For a patient with urethritis, collect a first-void urine sample or urethral swab and perform a validated NAAT for M. genitalium detection. Where possible, include testing for macrolide resistance mutations to guide therapy ¹ (Wi et al., 2019; Raj et al., 2022; Waites et al., 2023).