C ₆ Test as an Indicator of Therapy Outcome for Patients with Localized or Disseminated Lyme Borreliosis

Abstract

Management of Lyme disease would benefit from a test to assess therapy outcome. Such a test could be employed to ascertain if treatment of early Lyme disease was successful and would be helpful to clinicians assessing patients with lingering posttreatment symptoms. We reported recently that levels of the antibody to C 6 , a Borrelia burgdorferi-derived peptide that is used as an antigen in the C 6 -Lyme diagnostic test, declined after successful antibiotic treatment of Lyme borreliosis patients. We assessed retrospectively the change in anti-C 6 antibody titers in 131 patients with either early localized disease (erythema migrans) or disseminated disease. All of these patients were treated with antibiotics and were free of the clinical signs shown at presentation within 12 weeks after the initiation of treatment. Decreases in reciprocal geometric mean titers (rGMT) of the anti-C 6 antibody were quantified for the subpopulation of 45 patients whose baseline rGMT were >80 and whose second serum specimens were obtained at least 6 months after the baseline specimen. Eighty percent of this patient group (36 of 45) experienced a >4-fold decrease in their rGMT (P < 0.0003). These results suggest that a change in the anti-C 6 antibody titer may serve as an indicator of therapy outcome for patients with localized or disseminated Lyme borreliosis.

Diagnosis of Lyme Borreliosis

“…Philipp et al reported that 80% of a subset of patients treated for early localized or disseminated LB had a Ն4-fold decrease in their reciprocal geometric mean titers to C6 at 6 months or thereafter (255). Other studies have not confirmed these findings.…”

“…Those authors also reported that in another group of patients, 50% of those with early LB and 83% of those with late LB still had detectable C6 reactivity 8 to 15 years after treatment. Likely explanations for the discrepancies in the findings of Philipp and Peltomaa include differences in serum dilutions used to calculate the decline in antibodies, whether patients had sufficient titers at baseline to permit detection of a fourfold decline at least 6 months later, and/or the patient populations studied (250,255).…”

Dynamic Longitudinal Antibody Responses during Borrelia burgdorferi Infection and Antibiotic Treatment of Rhesus Macaques

“…Two of the most commonly used tests for diagnosis in North America are (i) the twotier test, which includes an enzyme-linked immunosorbent assay (ELISA) and Western blotting using antigen derived from wholecell lysates, and (ii) the C6 test, which detects antibodies to a specific peptide within a conserved region of the B. burgdorferi antigen VlsE (5,30,32). The C6 test has also been used experimentally for evaluation of treatment efficacy (36,37).…”

Comparison of an automated Borrelia indirect chemiluminescent immunoassay (CLIA) with a VlsE/C6 ELISA and Immunoblot

“…Since the handling time is minimal, the CLIA is more cost-effective as compared to conventional ELISAs and thus is an alternative for large scale laboratories. In the light of that convalescence samples sometimes are required to prove LD [6], the CLIA is an affordable option. In conclusion, the Liaison Borrelia CLIA is a reliable screening test for automatization and is comparable with the VlsE/C6 ELISA.…”

“…Borrelia Outer surface protein C (OspC) [3] and Vmplike sequence expressed (VlsE) [4] are two plasmid encoded membrane proteins that both are immunodominant antigens. Furthermore, VlsE consists of one invariable region (IR6), which is extraordinary immunodominant [5,6]. Other antigens that have been useful in serology are p39 and p83 [7].…”