Lyme disease-the most common arthropod-borne illness in the United States-has become entrenched in the Northeast, upper Midwest, and northern California, and it is spreading to other regions of the country. Diagnosis and management remain a significant challenge because of the diverse manifestations of the disease and the limitations of current tests.
Lyme disease-the most common arthropod-borne illness in the United States-has become entrenched in the Northeast, upper Midwest, and northern California, and it is spreading to other regions of the country.1 Diagnosis and management remain a significant challenge because of the diverse manifestations of the disease and the limitations of current tests.
In response to this growing problem, the Infectious Diseases Society of America (IDSA) recently updated its clinical practice guidelines on Lyme disease.1 The most significant changes in the newer version of the guidelines, originally published in 2000, include the following:
• Information was added on human granulocytic anaplasmosis (HGA) and babesiosis, both of which are transmitted by Ixodes scapularis, the deer tick that transmits Lyme disease. HGA is caused by Anaplasma phagocytophilum; symptoms include headache, fever, chills, muscle pain, and fatigue. Babesiosis-a malaria-like parasitic infection-is usually asymptomatic in healthy persons but can be life-threatening in those who are elderly or who have compromised immune systems.
• A single dose of an antibiotic is recommended for treatment of some high-risk patients who have been bitten by a tick but do not show symptoms of Lyme disease. Eligibility criteria include the ability to reliably identify the attached insect as an I scapularis tick having been attached for an estimated 36 hours or longer, the ability to start preventive treatment within 72 hours of the time when the tick was removed, and the presence of ecological information indicating that the local rate of infection of these ticks with Borrelia burgdorferi is 20% or greater. Whether antibiotic prophylaxis after a tick bite will reduce the incidence of HGA or babesiosis is not known.
• The discussion and definition of "chronic," or post-Lyme disease, syndromes were expanded. The updated IDSA guidelines concluded that objective evidence of a previous B burgdorferi infection must be part of any acceptable definition of post-Lyme disease syndromes and did not recommend ongoing antibiotic therapy for patients with chronic symptoms who completed the initial course of treatment for Lyme disease. The guidelines also noted that long-term antibiotic therapy may be dangerous and may lead to complications, such as bloodstream catheter infection and Clostridium difficile colitis. Patients who have symptoms that persist after appropriate antibiotic treatment for Lyme disease are advised to consult with their physician.
For more information on the IDSA updated practice guidelines and a Lyme disease fact sheet for patients, visit the IDSA Web site at www.idsociety.org. For more information about Lyme disease diagnosis, management, and prevention, contact the American Lyme Disease Foundation (ALDF), Inc, PO Box 466, Lyme, CT 06371. Or, visit the organization's Web site at www.aldf.com. Tips on prevention from the ALDF are provided in the Box below.
Patients' best line of defense against Lyme disease is to examine themselves at least once each day and to remove any ticks before they become engorged with blood, according to the American Lyme Disease Foundation (ALDF). An infected deer tick usually cannot begin transmitting the Borrelia burgdorferi spirochete until it has been attached to its host for about 36 to 48 hours. Other measures you can offer patients who wish to reduce their risk of contracting Lyme disease include the following:
Wormser GP, Dattwyler RJ, Shapiro ED, et al. The clinical assessment, treatment, and prevention of Lyme disease, human granulocytic anaplasmosis, and babesiosis: clinical practice guidelines by the Infectious Diseases Society of America.
Clin Infect Dis.