Two urine samples consistently showed false-positive results. At least one urine fraction from each of the 10 samples examined tested false-positive. The LUAT results, unlike the highly reproducible IgG Western blot results, varied markedly. Each urine sample was divided into five equal fractions, or replicates, so that a total of 50 individual LUATs were performed. The LUAT was performed by the test’s manufacturer (IgeneX, Palo Alto, CA) on urine samples taken from 10 healthy volunteers who had no history or symptoms of Lyme disease. All samples from the same 10 healthy volunteers tested negative. The same results were obtained when the duplicate fractions of the same 21 samples were tested. On initial testing, two-thirds (14/21) of the patient samples tested positive for Lyme disease by standard IgG Western blot criteria the remainder tested negative. The laboratory performing the test was not aware of the results from the previous test. In accordance with current recommendations, the IgG test was considered positive if it revealed 5 or more of the 10 bands (indicative of antibodies) deemed significant for Lyme disease.ĭuplicate fractions of blood from the 21 patients with chronic Lyme disease symptoms were tested at separate times. Testing was performed at NEMC, a laboratory recognized by CDC as qualified to do so. These 21 blood samples were analyzed and compared with those from 10 healthy volunteers who had no history or symptoms of Lyme disease. All patients had been treated for acute Lyme disease symptoms with recommended antibiotics, but they had continued to suffer symptoms of fatigue, muscle and joint pains, or neurocognitive problems for at least six months thereafter. To perform the IgG Western blot, the investigators collected blood samples from 21 patients who met the case definition of Lyme disease established by the Centers for Disease Control and Prevention (CDC). Although the LUAT has not been approved by the Food and Drug Administration as a valid diagnostic test for Lyme disease, it is widely used, and the NIAID Lyme Disease Advisory Panel asked that it be further evaluated. The LUAT detects proteins derived from the bacterium in urine samples. The IgG Western blot is a licensed test used to screen blood samples for antibodies to the Lyme bacterium, Borrelia burgdorferi. Klempner, M.D., of NEMC and his scientific collaborators in New York, Connecticut and Washington, D.C., report their findings about the reliability of two Lyme disease tests: an IgG Western blot blood test and the Lyme urine antigen test, or LUAT. In the February 15 issue of the American Journal of Medicine, Mark S. The investigators included this evaluation because diagnostic tests for Lyme disease have been controversial due to problems with their ability to detect evidence of the Lyme bacterium and to distinguish it from closely related bacteria the lack of standardized materials used to perform the tests and variation within and among laboratories performing the tests. The proposed study included an evaluation of old and new tests used to diagnose and manage Lyme disease and other tick-borne diseases. In 1996, the National Institute of Allergy and Infectious Diseases (NIAID) awarded a five-year contract to the New England Medical Center (NEMC), Boston, MA, to study how chronic Lyme disease develops and how to improve its treatment. IgeneX testing has also been cited as problematic by the FDA.įebruReliability of Blood and Urine Tests for Lyme Disease Below is a statement from the NIH’s National Institute of Allergy and Infectious Diseases (NIAID) about the unreliability of IgeneX testing.
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