Lyme disease

Overview 
Theory 
Diagnosis 
Management 
Follow up 
Resources 

Last reviewed: 22 Nov 2024

Last updated: 08 Oct 2024

Lyme disease is an infectious disease transmitted to humans through the bite of infected ticks.

Erythema migrans develops at the site of tick bite usually within 1 to 2 weeks and is a pathognomic feature.

Constitutional symptoms such as fever, headache, myalgias, fatigue, and arthralgias may occur.

Complications of Lyme disease may be neurologic, cardiac, or musculoskeletal.

Mainstay of treatment is antibiotic therapy.

There is currently no vaccine; prevention is centered around reducing exposure to ticks.

Definition

Lyme disease is a zoonotic infection caused by a spirochete of genus Borrelia, which is transmitted to humans by ticks. Zoonotic diseases are transmitted between vertebrate animals and humans. Animals serve as the primary reservoir of Borrelia. Ticks become infected by feeding on an infected animal. The most common initial manifestation is a typical skin lesion known as erythema migrans. Later manifestations may include arthritis, or central nervous system or cardiac involvement.

History and exam

Key diagnostic factors

erythema migrans
constitutional symptoms

Full details

Other diagnostic factors

facial palsy
arthritis or arthralgia
regional lymphadenopathy
stiff neck
lymphocytoma cutis
acrodermatitis chronica atrophicans
atrioventricular (AV) block or myopericarditis
radiculoneuropathy
encephalomyelitis, peripheral neuropathy, encephalopathy

Full details

Risk factors

exposure to infected ticks
outdoor activities
tick bite duration

Full details

Diagnostic tests

1st tests to order

enzyme immunoassay or immunofluorescence assay

Full details

Tests to consider

Lyme-specific IgM and IgG (immunoblot assays)
skin biopsy culture
polymerase chain reaction (PCR)
ECG

Full details

Treatment algorithm

INITIAL

known high risk tick bite

ACUTE

erythema migrans

cardiac involvement

neurologic disease

arthritis

ONGOING

recurrent or persistent arthritis

Contributors

Authors

Janak Koirala, MD, MPH, FACP, FIDSA

Professor of Medicine and Infectious Diseases

Division of Infectious Diseases

Southern Illinois University School of Medicine

Springfield

Disclosures

JK declares that he has no competing interests.

Acknowledgements

Dr Janak Koirala would like to gratefully acknowledge Dr Tin Han Htwe and Dr Cristian A. Spiel, previous contributors to this topic.

Disclosures

THH and CAS declare that they have no competing interests.

Peer reviewers

Raymond J. Dattwyler, MD

Professor of Medicine and Microbiology/Immunology

Chief of Allergy, Immunology and Rheumatology

New York Medical College

Valhalla

Disclosures

RJD declares that he has no competing interests.

Ionita Catalina, MD

Assistant Professor of Neurology and Neurosurgery

SUNY at Buffalo

Stroke/Neurocritical Care

Millard Fillmore Gates Hospital - Kaleida Stroke Center

Buffalo

Disclosures

IC declares that she has no competing interests.

Graham Fry, MB, FRCSI, DTM&H

Lecturer in Tropical Medicine

University College Dublin

Medical Director

Tropical Medical Bureau

Ireland

Disclosures

GF declares that he has no competing interests.

Andras Lakos, MD, PhD

Physician

Centre for Tick-Borne Diseases

Budapest

Hungary

Disclosures

AL is an author of a reference cited in this topic.

Differentials
- Local inflammatory reaction to tick bite
- Tickbite allergy
- Cellulitis
More Differentials
Guidelines
- CDC Yellow Book: health information for international travel - Lyme disease
- 2020 guidelines for the prevention, diagnosis and treatment of Lyme disease
More Guidelines
Patient information
Lyme disease
More Patient information
Log in or subscribe to access all of BMJ Best Practice

Use of this content is subject to our disclaimer

Lyme disease

Summary

Definition

History and exam

Key diagnostic factors

Other diagnostic factors

Risk factors

Diagnostic tests

1st tests to order

Tests to consider

Treatment algorithm

known high risk tick bite

erythema migrans

cardiac involvement

neurologic disease

arthritis

recurrent or persistent arthritis

Contributors

Authors

Janak Koirala, MD, MPH, FACP, FIDSA

Disclosures

Acknowledgements

Disclosures

Peer reviewers

Raymond J. Dattwyler, MD

Disclosures

Ionita Catalina, MD

Disclosures

Graham Fry, MB, FRCSI, DTM&H

Disclosures

Andras Lakos, MD, PhD

Disclosures

Differentials

Guidelines

Patient information

Log in or subscribe to access all of BMJ Best Practice

Log in or subscribe to access all of BMJ Best Practice

Log in to access all of BMJ Best Practice