The Differential Diagnosis of Chronic Lyme Disease
Many patients referred for Lyme disease are often found to have a rheumatologic or neurologic diagnosis. Osteoarthritis, rheumatoid arthritis (RA), degenerative diseases of the spine and spondyloarthropathies are the most common rheumatologic conditions identified in these patients.[32,33,47] Some patients are found to have neurologic diseases, including multiple sclerosis (MS), demyelinating diseases, amyotrophic lateral sclerosis (ALS) and neuropathies. Some authors and patient advocates have proposed that in actuality Lyme disease is the true or underlying etiology in many patients who have received these alternative medical diagnoses.[30,48–50] This seems to be quite unlikely given that many of these diseases result in rather specific medical syndromes that do not concentrate in areas with heavy B. burgdorferi transmission, such as the Northeastern and upper Midwestern USA. Even if one were to stipulate that very atypical presentations of Lyme disease (i.e., resembling ALS) went unrecognized by public health authorities, and that surveillance numbers are skewed by too narrow a case definition, one would still expect to see clustering in areas where Lyme transmission is heaviest. This is not the case. MS, for instance, occurs at substantial rates in areas with little or no endemic transmission of B. burgdorferi, such as Washington state, USA, Northern Canada, Iceland and arctic Norway. Similarly, the medical literature fails to yield evidence that ALS, Parkinson's disease, RA or spondyloarthropathies cluster in areas with the highest incidence rates of Lyme disease. While there can certainly be clinical overlap between Lyme disease and other clinical entities, objective findings and studies will generally allow the clinician to differentiate between them.[53–55]
Syndromes such as fibromyalgia and chronic fatigue syndrome, as well as less specific chronic syndromes (variably called 'medically unexplained systems', 'functional pain syndromes' or 'chronic multisystem illness') account for most of the remaining patients who are referred for chronic Lyme disease. Unlike Lyme disease, these frustrating conditions generally lack objective clinical or histopathological abnormalities, and are dominated by subjective complaints and functional impairment.[56–58] Neither fibromyalgia nor chronic fatigue syndrome is known to geographically cluster with B. burgdorferi transmission. Fibromyalgia has been found to temporally follow Lyme disease in some cases: in a prospective study of 287 patients treated for confirmed Lyme disease, 22 (8%) went on to develop fibromyalgia within 5 months of treatment. Additional antibiotics were not beneficial. It must be noted that fibromyalgia and chronic fatigue can temporally follow a variety of infections, including, but not limited to, infection with B. burgdorferi.[56,60]
Expert Rev Anti Infect Ther. 2011;9(7):787-797. © 2011 Expert Reviews Ltd.
Cite this: Chronic Lyme Disease: The Controversies and the Science - Medscape - Jul 01, 2011.