CDC OKs new two-tier testing algorithm for Lyme disease
The CDC issued an updated recommendation for the serologic diagnosis of Lyme disease, endorsing the use of a two-tier testing algorithm that uses a second enzyme immunoassay, or EIA, in place of a western immunoblot assay.
The update, published in MMWR, followed the FDA’s clearance last month of four previously cleared Lyme disease tests manufactured by ZEUS Scientific with new indications for use in the modified two-tier testing process.
The CDC previously recommended a two-tier testing algorithm that included a sensitive first-tier test — either an EIA or immunofluorescence assay — followed by a supplemental immunoblot assay if the first test resulted in a positive or equivocal result. Under the new recommendation, when cleared by the FDA for Lyme disease testing, “serologic assays that utilize EIA rather than western immunoblot assay in a two-test format are acceptable alternatives for the laboratory diagnosis of Lyme disease.”
According to the update, “clinicians and laboratories should consider serologic tests cleared by FDA as CDC-recommended procedures for Lyme disease serodiagnosis” — a standard based on the criteria established at the 1994 Second National Conference on Serologic Diagnosis of Lyme Disease.
The report from that conference offered guidance on the development of future tests. It advised that “evaluation of new serologic assays include blind testing against a comprehensive challenge panel and that new assays should only be recommended if their specificity, sensitivity and precision equaled or surpassed the performance of tests used in the recommended two-test procedure,” the authors of the new recommendation wrote. – by Joe Gramigna
Disclosures: The authors report no relevant financial disclosures.
FDA. FDA clears new indications for existing Lyme disease tests that may help streamline diagnoses. https://www.fda.gov/news-events/press-announcements/fda-clears-new-indications-existing-lyme-disease-tests-may-help-streamline-diagnoses. Accessed August 16, 2019.