Tick-borne Encephalitis and Positive Borrelial Antibodies

Study Overview
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Brief Summary
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In Slovenia, tick-borne encephalitis and Lyme borreliosis are both endemic diseases with high incidence rates and they are both transmitted by a bite of infected Ixodes ricinus tick. In clinical practice, tick-borne encephalitis is confirmed by demonstration of tick-borne encephalitis antibodies in serum of a patient with compatible clinical presentation and cerebrospinal pleocytosis. Patients with Lyme meningitis or meningoradiculitis also have cerebrospinal pleocytosis, however the presence of borrelial antibodies in serum does not attest Lyme neuroborreliosis. Patients with tick-borne encephalitis and positive borrelial antibodies in serum, but not fulfilling criteria for Lyme neuroborreliosis, are often being treated with antibiotics in several European countries due to the possibility of double infection. The investigators hypothesise that such patients do not benefit from antibiotics. Such an approach may appear safe regarding the possibility of borrelial infection, however it can also be associated with detrimental consequences such as antibiotic related adverse reactions, negative epidemiological impact on bacterial resistance, and intravenous catheter related complications.

Official Title
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Management of Patients With Tick-borne Encephalitis and Positive Anti-Lyme Borreliae Antibody Results

Conditions
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Tick-borne Encephalitis

Intervention / Treatment
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* Drug: Doxycycline
* Drug: Symptomatic therapy
* Other: Questionnaire


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 18 years or older clinical picture compatible with tick-borne encephalitis, clear cerebrospinal fluid, cerebrospinal pleocytosis (leucocytes in cerebrospinal fluid >5 x 106/)L, positive serum immunoglobulin M (IgM) and immunoglobulin G (IgG) antibodies against tick-borne encephalitis virus, positive serum IgG antibodies against Lyme borreliae. Exclusion Criteria: isolation of B.burgdorferi sensu lato from cerebrospinal fluid, positive intrathecal borrelial antibody production index, seroconversion of borrelial IgG antibodies, presence of erythema migrans and/or borrelial lymphocytoma in the last month, Bannwarth syndrome.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Doxycycline, Doxy®<br>Beside symptomatic therapy, patients will receive oral doxycycline 100 mg (Doxy®) twice daily. Patients will answer a questionnaire asking about the presence and frequency of nonspecific symptoms such as headache, fatigue, arthralgia, myalgia. | Drug: Doxycycline<br>* Beside symptomatic therapy, patients will receive oral Doxycycline 100 mg, Doxy® twice daily.<br>|
| Other: No antibiotics<br>Patients will receive symptomatic therapy (paracetamol, Lekadol®, granisetron, Kytril®, metamizol, Analgin®, parenteral hydration with saline). Patients will answer a questionnaire asking about the presence and frequency of nonspecific symptoms such as headache, fatigue, arthralgia, myalgia. | Drug: Symptomatic therapy<br>* Patients will receive symptomatic therapy with antipyretics, analgetics, antiemetics, and parenteral hydration: metamizole, Analgin®, paracetamol, Lekadol®, thiethylperazine, Kytril®, saline.<br>Other: Questionnaire<br>* Subjects will be asked to answer a questionnaire asking about the presence and frequency of nonspecific symptoms such as headache, fatigue, arthralgia, myalgia.<br>|
| Other: Healthy controls<br>Patients will be asked to refer a spouse to serve as a control. If unmarried they will be asked to refer a family member or a friend of +/- 5 years to serve as a control. Control subjects will be asked to answer a questionnaire asking about the presence and frequency of nonspecific symptoms such as headache, fatigue, arthralgia, myalgia. | Other: Questionnaire<br>* Subjects will be asked to answer a questionnaire asking about the presence and frequency of nonspecific symptoms such as headache, fatigue, arthralgia, myalgia.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Objective manifestations of Lyme borreliosis |  | one year | 
| Frequency of nonspecific symptoms such as headache, fatigue, arthralgia, myalgia |  | one year |