Issues in the diagnosis and treatment of lyme disease.
Department of Medicine (Infectious Diseases), Falmouth Hospital, USA.
Since the identification of the causative organism more than 30 years ago, there remain questions about the di-agnosis and treatment of Lyme Disease. In this article, what is known about the disease will be reviewed, and approaches to the successful diagnosis and treatment of Lyme disease described. In considering the diagnosis of Lyme disease, a major problem is the inability of documenting the existence and location of the bacteria. After the initial transfer of the bacteria from the Ixodes tick into the person, the spirochetes spread locally, but after an initial bacteremic phase, the organisms can no longer be reliably found in body fluids. The bacteria are proba-bly present in subcutaneous sites and intracellular loci. Currently, the use of circulating antibodies directed against spe-cific antigens of the Lyme borrelia are the standard means to diagnose the disease, but specific antibodies are not an ade-quate means to assess the presence or absence of the organism. What is needed is a more Lyme-specific antigen as a more definitive adjunct to the clinical diagnosis. As for the treatment of Lyme disease, the earliest phase is generally easily treated.
But it is the more chronic form of the disease that is plagued with lack of information, frequently leading to erroneous recommendations about the type and du-ration of treatments. Hence, often cited recommendations about the duration of treatment, eg four weeks is adequate treatment, have no factual basis to support that recommendation, often leading to the conclusion that there is another, per-haps psychosomatic reason, for the continuing symptoms. B. burgdorferi is sensitive to various antibiotics, including pe-nicillins, tetracyclines, and macrolides, but there are a number of mitigating factors that affect the clinical efficacy of these antibiotics, and these factors are addressed.
The successful treatment of Lyme disease appears to be dependent on the use of specific antibiotics over a sufficient period of time. Further treatment trials would be helpful in finding the best regimens and duration periods. At present, the diagnosis of Lyme disease is based primarily on the clinical picture. The pathophysiology of the disease remains to be determined, and the basis for the chronic illness in need of additional research. Whether there is continuing infection, auto-immunity to residual or persisting antigens, and whether a toxin or other bacterial-associated product(s) are responsible for the symptoms and signs remains to be delineated.
Labels: B. burgdorferi, bacteria, causative organism, diagnosis, Ixodes tick, lyme disease, signs, symptoms