Searching for Persistence of Infection in Lyme Disease

Lyme Disease Clinical Trial

Official title: Searching for Persistence of Infection in Lyme Disease

Status Completed

Clinical Trial Summary

Background:

Lyme disease is an infection caused by Borrelia burgdorferi, a bacteria that is transmitted to humans by ticks. It can cause many different symptoms including rash, fever, headache, meningitis (infection of the central nervous system), and arthritis. While most patients improve after taking antibiotics, some patients continue to have symptoms. It is currently unknown why some patients continue to have symptoms. One possibility is that the antibiotics have not successfully gotten rid of all of the bacteria. Current tests for Lyme disease cannot tell whether the bacteria have been successfully eliminated from the body.

Xenodiagnosis is a way to look for Borrelia bacteria using the animal that usually hosts them, Ixodes scapularis (also known as the deer tick). This method takes advantage of the evolution of the bacteria and the insect that transmits the infection, which can make the insect particularly good at finding the agent. In studies of animals, xenodiagnosis may be more sensitive than current tests for detecting the presence of the Lyme disease bacteria. Researchers are interested in using xenodiagnosis to determine whether uninfected ticks that feed on humans who have been infected with Lyme disease bacteria can detect the continued presence of live bacteria.

Objectives:

• To determine whether xenodiagnosis can be used to successfully investigate the presence of Lyme disease bacteria.

Eligibility:

1. Individuals at least 18 years of age who are in one of the following categories:

2. Have had the erythema migrans rash (a symptom of Lyme infection) and received antibiotic therapy less than 4 months ago (but have not had antibiotics in the previous month).

3. Have the erythema migrans rash and received less than 2 days of antibiotic therapy.

4. Have been diagnosed with early or late Lyme disease, have received antibiotic therapy, but still have high levels of antibodies against the bacteria at least 6 months after therapy, and have not received antibiotics in the past 3 months.

5. Have been diagnosed with early or late Lyme disease, have received antibiotic therapy, and have new complaints of fatigue or other symptoms that are persistent for at least 6 months after completion of antibiotic therapy, and have not received antibiotics in the past 3 months.

6. Have been diagnosed with Lyme arthritis and have not yet received antibiotic therapy.

7. Healthy volunteers who have not had Lyme disease will also be included in this study.

Design:

• Participants will have an initial visit for a physical examination, medical history, and blood sample.

• For the first study visit, researchers will place a strip of filter paper or a small plastic container with 20 to 30 disease-free ticks on the participant s skin. If possible, the ticks will be placed at the site of a Lyme disease rash or another suspicious area, or on the nondominant forearm. Participants will be asked to keep the ticks in place, and will keep a diary card at home to record any symptoms or problems.

• The ticks will be collected 4 to 6 days after placement. At that visit, participants will have a skin biopsy taken of the area tested, a blood sample will be collected, and participants will receive a new diary card to keep until the next clinic visit.

• After 1 month, participants will provide a final blood sample, and will receive a follow-up phone call 2 months afterward.

Clinical Trial Description

Lyme disease is the most common vector borne disease in the United States. Although antibiotic therapy is clinically effective in treating the symptoms of Lyme disease for most patients early in the course of disease, a significant number of patients who receive therapy report persistent symptoms. The cause of persistent symptoms after antibiotic therapy for Lyme disease is an area of great controversy. Recent studies have shown that the organism (Borrelia burgdorferi) may persist in animals after antibiotic therapy and can be detected by using the natural tick vector (Ixodes scapularis) to acquire the organism through feeding (xenodiagnosis). Whether this occurs in humans is unknown. Currently available tests for human Lyme disease do not allow determination of persistent infection after antibiotic therapy.

In this proposal, the utility of xenodiagnosis for identifying persistence of B. burgdorferi in treated human Lyme disease will be tested in up to 120 subjects with various stages of Lyme disease with 30 healthy adults to serve as controls. Subjects will be followed for approximately 3 months. In Objective #1, subjects who have the characteristic erythema migrans (EM) rash and have been treated with antibiotics early (within 3 weeks of infection) in the course of Lyme disease will be tested. After completion of antibiotic therapy, 25-30 larval Ixodes ticks will be allowed to feed on the subject and biopsies of the EM site will be performed. Repleted ticks will be collected and tested for the presence of B. burgdorferi. In Objective #2, similar studies will be performed, but enrollment will target subjects with elevated C6 (region 6 of the VlsE surface protein of B. burgdorferi) antibody levels. In Objective #3, patients with persistent symptoms after antibiotic therapy will be evaluated. As an attempt to increase the chances of a positive xenodiagnosis in humans, patients with EM who are in the first 2 days of antibiotic therapy and patients with untreated Lyme arthritis will also be evaluated. Evidence that B. burgdorferi can be recovered by xenodiagnosis after antibiotic therapy in subjects with continued symptoms would change the current paradigm for potential mechanisms of disease and provide researchers and clinicians a tool for identifying patients with persistent infection. In Objective #4 we will assess the safety of the planned xenodiagnostic procedure in humans. All individuals who underwent xenodiagnosis under the study will be assessed for adverse events. ;

Related Conditions & MeSH terms

• Lyme Disease

• NCT number: NCT01143558
• Study type: Interventional
• Source: National Institutes of Health Clinical Center (CC)
• Status: Completed
• Phase: Early Phase 1
• Start date: November 4, 2010
• Completion date: December 30, 2014