A comparison of Lyme disease serologic test results from four laboratories in patients with persistent symptoms after antibiotic treatment.
http://doi.org/10.1093/cid/ciu703
Abstract
Background. As the incidence of Lyme disease (LD) has increased, a number of "Lyme specialty laboratories" have emerged, claiming singular expertise in LD testing. We investigated the degree of interlaboratory variability of several LD serologic tests—whole cell sonicate (WCS) enzyme-linked immunosorbent assay (ELISA), IgM and IgG Western blots (WB), and an ELISA based on the conserved sixth region of VlsE (C6)—performed at one university laboratory, one commercial laboratory and two laboratories that specialize in LD testing.
Methods. Serum samples from 37 patients with post-treatment Lyme syndrome (PTLS), as well as 40 medically healthy controls without prior Lyme disease, were tested independently at the four laboratories.
Results. In general there was little difference among the labs in the percentage of positive test results on the ELISAs and IgG WBs, although the number of discordant results was often high. When in-house criteria for positivity were used at the two specialty laboratories, specificity at one lab declined considerably on both the IgM and IgG WB. The CDC 2-tiered criteria improved overall concordance. At the two laboratories that performed the C6 ELISA, the percentage of positive tests was comparable to that of the WCS ELISA while providing higher specificity. The IgM WB performed poorly in our patient population of individuals with later stage illness, a result consistent with previous studies.
Conclusions. While there was surprisingly little difference among the labs in percentage of positive results on most assays using CDC criteria, interlaboratory variability was considerable and remains a problem in LD testing.
http://doi.org/10.1093/cid/ciu703
[published in IDSA journal, late stage patients, what is said about antibody testing in that population, if anything]Fallon BA, Pavlicova M, Coffino SW, Brenner C.
Clinical Infectious Diseases, online before print 2014 Sep 2. pii: ciu703.http://doi.org/10.1093/cid/ciu703
Abstract
Background. As the incidence of Lyme disease (LD) has increased, a number of "Lyme specialty laboratories" have emerged, claiming singular expertise in LD testing. We investigated the degree of interlaboratory variability of several LD serologic tests—whole cell sonicate (WCS) enzyme-linked immunosorbent assay (ELISA), IgM and IgG Western blots (WB), and an ELISA based on the conserved sixth region of VlsE (C6)—performed at one university laboratory, one commercial laboratory and two laboratories that specialize in LD testing.
Methods. Serum samples from 37 patients with post-treatment Lyme syndrome (PTLS), as well as 40 medically healthy controls without prior Lyme disease, were tested independently at the four laboratories.
Results. In general there was little difference among the labs in the percentage of positive test results on the ELISAs and IgG WBs, although the number of discordant results was often high. When in-house criteria for positivity were used at the two specialty laboratories, specificity at one lab declined considerably on both the IgM and IgG WB. The CDC 2-tiered criteria improved overall concordance. At the two laboratories that performed the C6 ELISA, the percentage of positive tests was comparable to that of the WCS ELISA while providing higher specificity. The IgM WB performed poorly in our patient population of individuals with later stage illness, a result consistent with previous studies.
Conclusions. While there was surprisingly little difference among the labs in percentage of positive results on most assays using CDC criteria, interlaboratory variability was considerable and remains a problem in LD testing.
http://doi.org/10.1093/cid/ciu703
Comment:
Here is a link for anyone who wants to download the full article:
https://www.yousendit.com/download/ZUcwWGJKTlFiR0pESjhUQw
Lab B in the study uses the same diagnostic criteria as iGeneX, so I’m guessing that Lab B is iGeneX. Or is there another lab out there that uses the same diagnostic criteria?
(I'll try to update this if I get an answer.)
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