Lyme tests: rashes, bands, bones of contention
This is the second of a three-part series on controversies over diagnosing and treating Lyme disease. This week will focus on controversies over complicated Lyme testing.
Guidelines condoned by the U.S. Centers for Disease Control and Prevention allows a tick-bitten, symptomatic person with Lyme’s telltale bull’s-eye rash to immediately get a prescription for inexpensive, highly effective antibiotics from a doctor. But rash-less victims are not so lucky, for they are instead thrown into the now nationally contentious area of testing for the bacterial spirochete Borrelia burgdorferi.
There are two current tests for Lyme. The first is an enzyme-linked immunosorbent assay, or ELISA, which measures antibody levels. The second is the Western immuno-blot assay, or Western blot, which identifies proteins particular to Lyme.
Unfortunately for the rash-free patient, neither test is very accurate.
According to Dr. Joseph J. Burrascano, board member of the International Lyme and Associated Diseases Society ( ILADS), ELISA’S accuracy rate is only 30 to 50 percent.
Many doctors will readily send out for ELISA results as it is relatively inexpensive. But speaking at the recent Lyme forum sponsored by the Rappahannock League for Environmental Protection in Washington, retired Sibley Hospital internist Tom Connally frankly warned the audience, “don’t bother with the ELISA,” instead suggesting they request the Western blot.
Connally explained that if a patient is tested too soon – within two weeks after infection – their body has not had enough time for antibodies to form (two to five weeks) and induce a positive ELISA.
Possibly unaware of ELISA’S inaccuracy – or using CDC’S Lyme “surveillance” guidelines versus diagnostic guidelines – many doctors will stop testing there. If they do pro- ceed with the more expensive Western blot, with its higher “specificity” to Lyme of 90 percent, the accuracy (or “sensitivity”) of this test is only 30 percent – a statistic mainly brought on by human error.
The Western blot detects two types of antibodies which, if present, have been enzymatically cut into segments of varying lengths and run from end to end through an electrophoretic gel. The problem occurs when the gel analyzer eyeballs “bands” to see if certain segments exist that would claim a positive Western blot for that patient. As lesser-containing antibody bands are harder to see, these bands can be missed entirely.
But there is one big “band” bone of contention between two notable organizations at the controversy’s epicenter: ILADS (whose stance largely benefits Lyme patients) and the Infectious Disease Society of America (whose stance benefits others, such as insurance companies), according to the Lyme
Disease Association’s website.
In a January 2012 letter signed by several members of Congress – including Virginia’s own Frank Wolf – it states that the “highly controversial” IDSA guidelines for Lyme disease “have been responsible for insurance company denials of Lyme disease treatments.”
The problem began when IDSA – which devised the guidelines largely behind closed doors – threw out two gel bands for diagnostic consideration. The other camp says many Lyme sufferers are not being diagnosed – and therefore treated – because of this exclusion. Unfortunately for Lyme sufferers, the CDC agrees with the IDSA.
In 2008, Connecticut Attorney General Richard Blumenthal announced that an antitrust investigation carried out by his office had “uncovered serious flaws” in the guidelines.
Further, Blumenthal said in a press release, “My office uncovered undisclosed financial interests held by several of the most powerful IDSA panelists.” Blumenthal claimed the investigation revealed conflicts of interest among panel members, including financial interests in “drug companies, Lyme disease diagnostic tests, patents, and consulting arrangement with insurance companies” – claims all denied by the IDSA.
Putting controversy aside, there exists another diagnostic problem: Other bacterial co-infections can be transmitted in the same tick bite with Lyme bacterium. According to Burrascano, Lyme has been redefined now as “a complex illness potentially consisting of multiple tick-delivered co-infections.”
According to Thomas Mather, director of the Rhode Islandbased Center for Vector-borne Disease, “. . . current research shows that one in four or five” of the black-legged deer tick carries Lyme. Just as alarming, most of these infected ticks also carry lesser-known but equally serious infections of malaria-like babesiosis, as well as ehrlichiosis, mycoplasmas, and bartonella. These bacteria – which require a different set of tests with some requiring other types of antibiotics – are often overlooked by doctors.
According to Mather, the D.C. area is “at the [Lyme] nexus” as there are “lone star ticks coming in from the south [and] deer ticks coming in from the north…” The lone star tick, per the CDC, can carry another mysterious bacterium called STARI (Southern TickAssociated Rash Illness), which has a Lyme-like rash. STARI has no reliable test currently.
Next week’s installment will consider controversy over Lyme treatments.