To ask the Secretary of State for Health what assessment he has made of the adequacy of blood tests as a tool for diagnosis of late-stage Lyme disease; and what other tools for diagnosis he is considering.
Blood testing to confirm late stage Lyme disease is undertaken for the national health service by the Health Protection Agency's (HPA) Lyme disease Reference Laboratory. This laboratory is fully accredited and the tests conform to the internationally agreed testing criteria for "Borrelia burgdorferi", the causative agent of Lyme disease, based upon stringent interpretation of serological test results. The testing is a two stage process: testing for the presence of antibodies to "B. burgdorferi" followed by specific immunoblot (Western blot) tests on all specimens that react in preliminary tests. The significance of the results are then carefully assessed in the light of the patient's clinical signs and exposure history to ticks. This two stage testing procedure is carried out by world-renowned experts at the HPA's Lyme disease reference unit and supports the clinical assessment to provide the most accurate diagnosis. These tests are freely available to clinicians in the NHS. A small group led by the Inspector of Microbiology reviewed the testing methodology in 2006 and we are satisfied that the tests available to the NHS are adequate for the diagnosis of late-stage Lyme disease.
Molecular diagnostic tests have been developed for detection of "B. burgdorferi" and can be a useful in particular circumstances such as a diagnostic test on joint fluids in patients with suspected chronic Lyme arthritis. Such tests are not yet considered useful as a routine diagnostic tool. Direct detection by culture of "B. burgdorferi" is not useful for the diagnosis of late-stage Lyme disease.
The Chief Medical Officer's Inspector of Microbiology undertook a thorough investigation in 2006 of unorthodox and unvalidated blood tests offered by some non-NHS practitioners to make a diagnosis of Lyme disease in patients with medically unexplained symptoms similar to those of late stage Lyme disease. He found such unvalidated tests wholly unsuitable for the diagnosis of late-stage Lyme disease. His report is available at: