Are UK Doctors Overdiagnosing Lyme Disease?
The HPA notes an increasing trend for some medical practitioners to diagnose Lyme disease using unvalidated laboratory tests or to rely on the diagnosis when patients have a number of serious but non-specific symptoms. This includes patients who have likely not been exposed to ticks but who are, regardless, treated for suspected Lyme disease with potentially dangerous antibiotics and other medications. In addition to the risk of liver damage, gastrointestinal problems and other possible complications from the use of parenteral cephalosporins and other antibiotics, there is the risk of creating antibiotic resistance and thus endangering the general population.
Dangers of Misdiagnosing Lyme Disease
Another risk noted by the HPA is that doctors that jump to a diagnosis of Lyme disease may overlook clinically important symptoms and miss the opportunity for diagnosing and treating a patient early in the development of diseases such as Multiple Sclerosis, or even Alzheimer’s disease. Tests that the UK HPA specifically warns against include:
- LUAT – Lyme Urine Antigen Test
- QRIBb test
- LTT Lymphocyte transformation test
- Unorthodox applications of immunoblots
Unreliable Lyme Disease Tests
The report on these tests was prepared by Professor Brian Duerden, the Inspector of Microbiology and Infection Control, UK Department of Health. The LUAT claims to test for Borrelia burgdorferi antigens in the urine of patients suspected of infection with Lyme disease. This test has been found to yield a high number of false positives, possibly putting patients at risk of unnecessary exposure to antibiotics and delays in accessing treatment for the illness that is actually causing their symptoms. The QRIBb test is a type of fluorescent microscopy that purports to identify Lyme disease bacteria in the blood or other body fluids or tissues taken from patients. This test has not been validated and is considered, by Duerden and colleagues, to be unreliable and with no scientific basis. The LTT is also regarded as an unreliable Lyme disease test, as are unorthodox applications of immunoblots.
Early Testing for Lyme Disease
The UK HPA goes on to warn that even those antibody tests it does consider sensitive and reliable enough to diagnose Lyme disease are not helpful in the first few weeks of infection as patients will not always have built up sufficient antibody levels to prove seropositive on such tests. Late-stage Lyme disease rarely tests as seronegative according to the HPA, although many Lyme disease advocates disagree on this matter. Having additional polymerase chain reaction (PCR) tests of joint tissue can be helpful to confirm the presence of bacteria but such tests are not seen as reliable for testing cerebrospinal fluid.
Self-Diagnosing Lyme Disease
The confusion surrounding Lyme disease tests is all too apparent, with many patients resorting to sending their own samples to labs such as IGeneX. Unfortunately, laboratories may then rely on patient satisfaction for their success, rather than the accuracy of Lyme disease tests, and patients looking for a diagnosis of Lyme disease are unlikely to send samples for further testing, or recommend others to do so, following a negative result.
New Lyme Disease Testing Methods
Further research into the sensitivity, specificity and reliability of Lyme disease tests clearly needs carrying out, with new tests such as VOVO LIPS still undergoing investigation and the prospect of xenodiagnosis appealing to some with Chronic Lyme disease. Patients in the UK might feel short of options for Lyme disease testing but it does seem that physicians are becoming better able to access information on diagnosing the infection, whereas recent years have seen a continued denial of the presence of Lyme disease in the UK and resulting scarcity of laboratories offering reliable Lyme disease tests.
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