Improved Clinical Sensitivity for Detection of Antibodies to Borrelia burgdorferi
Jyotsna S Shah, Iris Du Cruz, William Narciso, Wai Lo and Nick S Harris
Igenx Inc.
Abstract
We evaluated the Western blot (WB) assay for Borrelia burgdorferi (BB) with in-house developed strips prepared using a mixture of two strains of BB – B31 and 297. All of the WB strips were scored positive or negative as per Centers for Disease Control and Prevention (CDC) and inhouse interpretive criteria. The in-house criteria for both immunoglobulin M (IgM) and IgG WB positivity is two bands and includes bands 31 and 34, which are not included in the CDC criteria. Of the 88 sera from treated patients (including 71 from US and 17 from Europe) with confirmed Lyme disease at various stages, the in-house prepared WB strips with CDC band interpretation had a sensitivity of 71 and 82% for IgM and IgG, respectively. Using the in-house interpretive criteria, the sensitivity for the IgG WB increased by 14%. The most significant increase (from 60 to 85%) was within the first year of infection, allowing detection of almost 97% of the samples. For 276 controls that included samples with antibodies to other tick-borne diseases, autoimmune diseases, viral diseases, presumed syphilis and normal controls without any known infections, the specificity of the in-house blot was 97 and 100% using the CDC interpretive criteria and 93.5 and 95% using the inhouse criteria for IgM and IgG, respectively. By removal of patients that were positive for antibodies to the band at 31kDa but who tested negative for antibodies to the recombinant outer surface protein A (OspA) antigen, which migrates at 31kDa, the specificity increased to >97% for both IgM and IgG. The use of a combination of two strains of BB, B31 and 297, improved IgM assay sensitivity and the expanded interpretation of the banding pattern improved the sensitivity of the IgG WB assay. Furthermore, the data shows that the IgM WB can be useful in the diagnosis of Lyme disease in patients beyond one month of disease onset if the recombinant OspA antigen testing is performed on sera that are positive for a band that migrates at 31kDa.
Keywords
Lyme disease, Borrelia burgdorferi, Western blot, tick-borne disease
Disclosure: The authors are employees of IGeneX, Inc.
Acknowledgements: We thank the US Centers for Disease Control and Prevention (CDC) for providing the Lyme Serum panel and Borrelia burgdorferi-specific monoclonal antibodies; Brian Fallon from Columbia University for providing sera from patients with neuroborreliosis; Armin Schwarzbach from Borreliose Centrum in Augsburg, Germany, for providing sera from European patients with Lyme Disease; and Mary York for comments and discussions.
Received: 27 July 2010 Accepted: 15 September 2010
Citation: European Infectious Disease, 2010;4(2):56–60
Correspondence: Jyotsna S Shah, IGeneX, Inc., 797 San Antonio Road, Palo Alto, CA 94303, US. E: jyotsna [at] aol [dot] com