Implementation of a proficiency testing program for Lyme disease in New York State

Nine proficiency test events for Lyme disease (Borrelia burgdorferi) antibody were carried out from October 1988 to January 1992 by the New York State Department of Health, Albany, Overall sensitivity for the 846 participants averaged 95.4%, with varying sensitivities of 98.7% for users (71 laboratories) of immunofluorescence assays, 97.4% for users (144 laboratories) of solid-phase fluorescence immunoassays, and 94.6% for users (631 laboratories) of enzyme immunoassays. Thirty percent of the enzyme immunoassay laboratories tested at greater than or equal to 98.4% sensitivity by the DiaMedix test kit (DiaMedix Corp, Miami, Fla) and MarDx test kit (MarDx Diagnostics Inc, Scotch Plains, NJ), while 7% tested at less than or equal to 83% by the Access test kit (Access Medical Systems Inc, Branford, Conn) and the Cambridge BioScience test kit (Cambridge BioScience, Worcester, Mass). Overall specificity was 98.8%, with specificities greater than 99% for both solid-phase fluorescence immunoassay and enzyme immunoassay users and 92.9% for immunofluorescence assay users. Cross-reactivity with Treponema pallidum antibody was high for the Hillcrest (Hillcrest Biologicals, Cypress, Calif) (30%) and Wampole (Wampole Laboratories, Cranbury, NJ) (25%) immunofluorescence assay test kit users and for the MarDx (30%) and 3M (3M Diagnostics Systems Inc, Santa Clara, Calif) (24%) enzyme immunoassay test kit users. Laboratories that tested by the Wampole immunofluorescence assay test kit had also high cross-reactivity (25%) against heterophile antibody.