IDSA updates Lyme disease recommendations

November 2006

New recommendations regarding the treatment of Lyme disease have been released by the Infectious Diseases Society of America to help elucidate the epidemiology, features and diagnosis of the disease.

The new guidelines include the following:

• More information regarding the diagnosis and background of Lyme disease.
• The addition of borrelial lymphocytoma and acrodermatitis chronica atrophicans.
• The addition of human granulocytic anaplasmosis and babesiosis, both of which are deer tick-transmitted infections.
• The recommendation of a single dose of up to 200 mg of doxycycline as prophylaxis for certain patients >8 years of age who have been bitten by an engorged, nymphal-stage deer tick.
• A proposed definition for post-Lyme disease syndrome.

“The updated guidelines were an evidence-based approach and there are extensive references for the scientific evidence that formed the basis for these guidelines,” said Eugene D. Shapiro, MD, FAAP, one of the authors of the guidelines and professor at Yale University School of Medicine Department of Pediatrics.

Disease transmission

The organisms that cause Lyme disease, human granulocytic anaplasmosis and babesiosis are found in mice and several other small mammals. Deer ticks acquire the infection from these mammals and subsequently may transmit the organisms to people.

Human granulocytic anaplasmosis is a tick-associated disease caused by a species of bacteria called Anaplasma phagocytophilum. According to the new guidelines, the most common symptoms for this condition are high fever and thrombocytopenia, myalgia muscle pain, fatigue and headache. Babesiosis is an infection that affects the red blood cells, and is transmitted through the bite of a deer tick. In the United States, most patients who are not immunocompromised are either asymptomatic or have only mild symptoms.

Patients who have these illnesses usually show symptoms such as the erythema migrans rash, facial nerve palsy or arthritis of a knee. In addition, flu-like symptoms such as fever, vomiting and joint pain, are also common.

Treatment

The guidelines state that the majority of patients with Lyme disease should be cured by a simple course of antibiotics. Occasionally, persons who are treated adequately with antibiotics may have persistence of some non-specific symptoms after the antibiotic course has been completed. The updated guidelines discuss post-Lyme disease Syndrome, which generally resolves within weeks without additional antimicrobial treatment.

The new guidelines also cover the so-called “chronic Lyme disease.” But the panel found no scientific evidence to support the existence of this condition.

Within both the updated and old guidelines, Lyme disease is considered a curable disease. “Patients should be reassured that Lyme disease is a curable infection like other spirochetal infections, and long-term antibiotic therapy is neither helpful nor safe,” Gary P. Wormser, MD, lead author of the guidelines and chief of the division of infectious diseases and vice chairman of the department of medicine at New York Medical College in Valhalla, N.Y., told Infectious Disease News. “There is also no convincing scientific evidence to justify prolonged antibiotic therapy or to support the existence of antibiotic-refractory, symptomatic Borrelia burgdorferi infection, which is also know as chronic Lyme disease.”

Doxycycline

According to the new guidelines, some tick bites that occur in patients >8 years of age may be treated with one dose of doxycycline if the Ixodes scapularis tick has been attached for at least 36 hours, if treatment can begin within 72 hours after the tick was removed and if the ecologic information indicates the local rate of infection with B. burgdorferi bacteria is over 20%.

For more information:

• 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. 2006;43:000.
• Wormser GP, Nadelman RB, Dattwyler RJ, et al. Practice guidelines for the treatment of Lyme disease by the Infectious Diseases Society of America. Clin Infect Dis. 2000;31 Suppl 1:1-14.