LabCorp to deny physicians access to western blot tests for Lyme disease

Labcorp will not offer a western blot test for individuals unless they are positive or equivocal for the Enzyme Immunoassay (EIA) or Immunoflorescense (IFA) screening tests for Lyme disease as of August 11, 2014.[1]

img-ldpr2Physicians have been disappointed by the poor sensitivity of the EIA or IFA screening tests for Lyme disease. The sensitivity of the whole-cell enzyme-linked immunosorbent assay (ELISA) to the B31 strain typically falls between 33-49% for patients presenting with an EM.[2-4] The sensitivity of the Food and Drug Administration (FDA) approved complement peptide C6 (C6-peptide) was 37% in 89 clinically well-defined individuals with LD [5] and 66.5% 403 sera from patients with an EM rash.[6]

Physicians have commonly ordered the western blot test for Lyme disease even in the absence of positive or equivocal testing. An IgM Western blot test can persist for at least 2 years in individuals with established Lyme disease infection. A IgM WB can persist for months to years in LD even if an individual is treated with antibiotics.[7-9]  An IgG can be positive in individuals with a negative screening test.

LabCorp’s decision to deny physician assess to western blot test for Lyme disease only makes testing sensitive than it already is.

It important that LabCorp reverse their position and allow physicians to continue to order western blot tests for Lyme disease even if the EIA and/or IFA are negative. Until then, clinicians may have to direct their patients to other labs.

  1. LabCorp newsletter for clients. Lyme disease testing now employs a two-tier antibody standard, Available from https://  Last accessed 8/16/14.
  2. Aguero-Rosenfeld ME, Nowakowski J, Bittker S, Cooper D, Nadelman RB, Wormser GP. Evolution of the serologic response to Borrelia burgdorferi in treated patients with culture-confirmed erythema migrans. J Clin Microbiol, 34(1), 1-9 (1996).
  3. Trevejo RT, Krause PJ, Sikand VK et al. Evaluation of two-test serodiagnostic method for early Lyme disease in clinical practice. J Infect Dis, 179(4), 931-938 (1999).
  4. Aguero-Rosenfeld ME, Nowakowski J, McKenna DF, Carbonaro CA, Wormser GP. Serodiagnosis in early Lyme disease. J Clin Microbiol, 31(12), 3090-3095 (1993).
  5. Ang CW, Notermans DW, Hommes M, Simoons-Smit AM, Herremans T. Large differences between test strategies for the detection of anti-Borrelia antibodies are revealed by comparing eight ELISAs and five immunoblots. Eur J Clin Microbiol Infect Dis,  (2011).
  6. Wormser GP, Schriefer M, Aguero-Rosenfeld ME et al. Single-tier testing with the C6 peptide ELISA kit compared with two-tier testing for Lyme disease. Diagn Microbiol Infect Dis,  (2012).
  7. Steere AC, Hardin JA, Ruddy S, Mummaw JG, Malawista SE. Lyme arthritis: correlation of serum and cryoglobulin IgM with activity, and serum IgG with remission. Arthritis Rheum, 22(5), 471-483 (1979).
  8. Massarotti EM, Luger SW, Rahn DW et al. Treatment of early Lyme disease. Am J Med, 92(4), 396-403 (1992).
  9. Craft JE, Grodzicki RL, Shrestha M, Fischer DK, Garcia-Blanco M, Steere AC. The antibody response in Lyme disease. Yale J Biol Med, 57(4), 561-565 (1984).

25 Replies to "LabCorp to deny physicians access to western blot tests for Lyme disease"

  • Justin Reilly, JD
    08/19/2014 (10:14 pm)

    Dr. Cameron, thank you for this excellent, succinct blogpost on such an important topic!

    This is completely outrageous! I’m sputtering here.

    And I knew ELISA was bad, but wasn’t aware it was THAT bad. And these numbers Dr. Camerson cites are for “well-defined” Lyme cases and EM cases, and it’s still only 30 – 70% sensitive! And I thought the state of affairs was insane as it was; now this takes the cake.

    Ashley, before I started going to Dr. Cameron, I was treated for Lyme by Derek Enlander, who runs the ME’cfs’ Center at Mt. Sinai (I have a dx of ME’cfs’ too). He doesn’t bother ordering ELISA because it is such a PoS, he just orders Western Blot and Igenex 2xPCR + Southern Blot. He uses Quest usually, IIRC (and sometimes LabCorp).

    • Ashley
      08/25/2014 (5:49 pm)

      Thank you for letting me know! My lyme’s test came back 0 but RMSF test was .54. My doctor thinks both of those tests are negative but I still feel sick after 10 days on Doxy. They won’t even consider that the tests could be wrong. It’s so frustrating. More doctors need to be informed about Tick diseases.

      • Steve
        04/18/2017 (2:16 am)

        Please stop writing “lyme’s” or “Lymes.” There is no “s”; it is neither possessive nor plural.

  • Debbie Thompson
    08/19/2014 (10:01 pm)

    When I read about this, I called a number that was posted in one of the groups. It turned out to be a billing number, but I was asked what state I was in, and was given another number 800 877-7831 Labcorp Customer Service. The woman I spoke with told me right away that this was not Labcorp’s doing, and that this came from the top. I asked her if ‘from the top’ meant the CDC/IDSA, she said yes. I told her she may be getting more calls about this, because it is known that the ELISA is bogus.

  • Jerry Seidel
    08/19/2014 (6:13 pm)

    I am certain this is due to the CDC’s attempt to take control of ALL testing. They are working on the language for a bill which will give them control of all lab tests. Lab tests(You send them the sample) are currently validated by another government approved method. The CDC doesn’t like that. They only want individuals with Lyme who make tons of antibodies to test positive. They want people who have a weak immune response due to the immunosuppression from Lyme to test negative. Most people have the immunosuppression. Chronic infections which exist below your immune systems radar are worth billions of dollars to the industry. It makes you sick off and on for life. The CDC helps the industry make money because the CDC is part of it. The CDC is allowed to own patents and profit from them. They actually own Lyme disease related patents and we are expected to trust they are looking out for us. The CDC IS BigPharma.

  • Ashley
    08/19/2014 (5:24 pm)

    This is stupid! Why would they deny that kind of testing? I was sooooo sick with RMSF and it took forever for the doctors to even figure it out. Now I have been bitten by a couple ticks again and the doctor is running a test for Lymes and RMSF but if they come back negative, I would want the western blot run because I KNOW something is wrong. I feel the same sickness as I did when I first KNEW something was wrong before. Ugh..this makes me mad. I hope LabCorp changes their minds on this. What other labs will run a western blot?

  • Donna Falcone
    08/19/2014 (5:19 pm)

    LabCorp should be boycotted. Patients can ask their doctors who rely on LapCorp to write them an Rx for blood work and then have it done anywhere else that takes their insurance. This is outrageous.

1 2 3 5

Join the Lyme Conversation
(Note: comments are moderated. You will see your comment after it has been reviewed.)

Some html is OK