Clinical evaluation of a Borrelia modified two-tiered testing (MTTT) shows increased early sensitivity for Borrelia burgdorferi but not other endemic Borrelia species in a high incidence region for Lyme disease in Wisconsin.

A modified two-tiered testing algorithm (MTTT; ZEUS Scientific) for Borrelia burgdorferi was recently FDA-cleared. We evaluated the MTTT algorithm to confirm Lyme disease and compared the findings in parallel with those obtained using standard two-tiered testing (STTT). Medical records from patients who submitted sera for laboratory confirmation of Lyme-like disease were reviewed. Three hundred twenty patient samples were run by the STTT and MTTT approaches and the results compared. Positive STTT samples were also positive by MTTT (94%). The MTTT confirmed the illness in 116 subjects (36%, P = 0.007), and 30 (26%) were negative by the STTT. Increased MTTT sensitivity was seen (P = 0.0005) during early infection. MTTT was insufficiently sensitive to identify other non-Borrelia spp. infections. Routine adoption of MTTT would improve sensitivity for early Lyme disease attributable to B. burgdorferi, but may not capture illness attributed to B. mayonii and B. miyamotoi.