Lyme disease or the Great Pretender is a very deceptive tick-borne disease. Borrelia burgdorferi, a corkscrew shaped spirochete bacteria is the main culprit. Lyme disease is a growing public health concern not only for those living in the Northern hemisphere or in endemic areas, but also for any person who loves to spend time outdoors.
The clinical diagnosis of Lyme Disease can be made based on the patient’s symptoms, his medical history, the objective clinical findings (Erythema migrans, facial palsy, arthritis ) and the exposure to ticks. (or appropriate exposure history to ticks). Generally lab testing is not required for the patients who developed the specific bull’s-eye rash. Unfortunately the rash only appears in an estimated 50% of infected patients.
In most of the cases health providers base their clinical diagnosis on the presence of the rash and typical symptoms, appropriate exposure history or recent travel to an endemic area. They would not consider a lab test if the patient does not present the above mentioned conditions.
Laboratory testing for Lyme Disease has several diagnostic approaches, serology being the most common.
INDIRECT TESTING. The most common diagnostic tests for Lyme disease are indirect ones. The lab tests used to diagnose Lyme Disease can confirm if a patient has been exposed to /infected by the Borrelia burgdorferi / Borrelia mayonii in the past. A two-step approach was suggested by CDC to make a diagnosis. They test for two class of antibodies (IgM and IgG) which develop a few weeks after the infection occurred and they remain in the blood forever.
The first tests performed are:
- Screening Immunoassay for Lyme antibody (EIA – Enzyme immunoassay) – available on both serum and cerebrospinal fluid
- Immunofluorescence (IFA)
- ELISA (Enzyme-linked immunosorbent assay ) detects antibodies to B. burgdorferi. It can not be used as the sole basis for diagnosis.
- Western Blot is a follow-up test which detects antibodies to several proteins of B.Burgdorferi. When the initial Elisa test results are positive or indeterminate. The test can be repeated after a few weeks.
DIRECT TESTING. The following tests are being referred to as “direct” tests because they detect the bacteria, not just body’s immune response to it.
- PCR (polymerase chain reaction) – PCR multiplies a key portion of DNA from the Lyme bacteria so that it can be detected. While PCR is highly accurate when the Lyme DNA is detected, it produces many false negatives.
- Antigen Detection Test – Antigen detection tests look for a unique Lyme protein in fluid (e.g. blood, urine, joint fluid). Sometimes people whose indirect tests are negative are positive on this test.
- Cerebrospinal fluid Test (CSF) detects the Borrelia antibodies in your cerebrospinal fluid. It is mostly used for patients presenting neurological symptoms.
Diagnosing Lyme (The Great Imitator or the Great Pretender) can be challenging. Given that the disease can mimic many other diseases such as: Fibromyalgia, Chronic Fatigue Syndrome, Multiple Sclerosis (MS), Amyotrophic Lateral Sclerosis (ALS) Parkinson’s, Alzheimer’s, Lupus, meningitis, environmental allergies (and the list goes on), many patients get mistakenly diagnosed. When left untreated it causes serious health consequences.