Lyme disease PCR testing is gaining significance as a vital diagnostic tool for Borrelia burgdorferi sensu lato (Bbsl) infections. However, a recent EU-wide external quality assessment study highlights critical gaps in current molecular diagnostics. While clinical symptoms and serology remain the primary diagnostic pillars, clinicians increasingly rely on PCR to detect Borrelia DNA. This comprehensive study evaluated 57 different amplification protocols across 34 international laboratories. Notably, the researchers uncovered substantial variations in performance across these settings.

Challenges in Lyme Disease PCR Testing

The research findings indicate that detection limits vary significantly between protocols. Some variations reached up to 10 genome equivalents (GE). Furthermore, common PCR targets like 16S rRNA, flagellin, and ospA showed similar performance levels. No single target significantly outperformed the others. However, the study observed that the same protocol often yielded different results on various Bbsl species. These differences even persisted between different strains within the same species. Additionally, many protocols exhibited cross-reactivity with relapsing fever Borreliae, which complicates diagnostic accuracy.

The Path Toward Diagnostic Standardization

Consequently, the study authors emphasize that standardizing PCR methods is essential for reliable Lyme borreliosis confirmation. In India, Lyme disease is increasingly recognized as an emerging threat. Reports from states like Himachal Pradesh and Haryana suggest the disease is often underdiagnosed. Therefore, accurate molecular testing helps differentiate Lyme disease from other tropical infections. Improving laboratory harmony will ensure more consistent patient outcomes. Clinicians should remain aware of these protocol variations when interpreting results.

Frequently Asked Questions

Why is standardization necessary for Lyme disease PCR?

Current protocols show vast differences in sensitivity and specificity. This variation leads to inconsistent results across different laboratories and Borrelia strains, potentially affecting patient care.

Which PCR targets are most effective for detecting Borrelia?

The study found that common targets like ospA, 16S rRNA, and flagellin perform similarly. Currently, no single genetic target is significantly superior to the others in a clinical setting.

Disclaimer: This content is for informational and educational purposes only and does not constitute medical advice. It is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Refer to the latest local and national guidelines for clinical practice.

References

Streibl BI et al. EU-wide external quality assessment study on the sensitivity and specificity of different DNA amplification protocols for the detection of Borrelia burgdorferi sensu lato. Ticks Tick Borne Dis. 2026 Jun 15. doi: undefined. PMID: 42296597.

Lager M, et al. Molecular detection of Borrelia burgdorferi sensu lato – An analytical comparison of real-time PCR protocols from five different Scandinavian laboratories. PLOS One. 2017.

Indian Council of Medical Research (ICMR). Lyme Disease: An Emerging Threat in India. Journal of the Association of Physicians of India. 2025.