You have been logged out of VisualDx or your session has expired.

Please reload this page and sign into VisualDx to continue.

..
  VisualDx Mobile   Select Language

Get VisualDx Mobile

There are VisualDx mobile apps available for iOS and Android devices.

You will need a VisualDx account to use the mobile apps.



Already have an account? Sign In or
sign up for a free trial.

Users with VisualDx accounts earn CME credits for using VisualDx.

Already have an account? Sign In or
sign up for a free trial.

Create a Personal Account

E-mail (username)
Password
Verify Password
First Name
Last Name

Personal Account Created

Mobile Access

You can now download VisualDx for your iOS and Android devices. Launch the VisualDx app from your device and sign in using your VisualDx personal account username and password.

CME Certification

Sign in with your personal account to earn and claim CME credits through VisualDx. Credits can be earned by building a differential or looking up a diagnosis.

Version: 7.09.1401   (build 62b8f0e)
Select Language


Select Region

Send us your feedback

E-mail
Message
This field is required

Oops! There was an issue during submission. Please try again. If the problem persists, email feedback@visualdx.com with your feedback.

Thank You!

We appreciate your feedback and you will be hearing from us soon.

OK

Share This Page

Thank You!

We have sent an e-mail with a link to the current page.

OK

E-mail This Patient Information Sheet

Thank You!

We have sent an e-mail with this patient information.

OK

Image Contributors

Individuals

  • Christine Ahn MD
    Carl Allen DDS, MSD
    Brandon Ayres MD
    Howard P. Baden MD
    Robert Baran MD
    Keira Barr MD
    Gregory J. Basura MD, Ph.D
    Donald Belsito MD
    Jeffrey D. Bernhard MD
    Jesse Berry MD
    Victor Blanco MD
    Benjamin R. Bohaty MD
    William Bonnez MD
    Sarah Brenner MD
    Robert A. Briggaman MD
    Robert Brodell MD
    Roman Bronfenbrener MD
    Walter Brooks MD
    William Buckley MD
    Philip Bulterys MD, PhD (candidate)
    Susan Burgin MD
    Sonya Burton MD
    Sean P. Bush MD, FACEP
    Jeffrey Callen MD
    Scott Camazine MD
    Michael Cardwell
    Shelley D. Cathcart MD
    Robert Chalmers MD, MRCP, FRCP
    Chia-Yu Chu MD, PhD
    Flavio Ciferri MD
    Maria Rosa Cordisco MD
    Noah Craft MD, PhD
    John T. Crissey MD
    Harold E. Cross MD, PhD
    Charles Crutchfield III MD
    Adriana Cruz MD
    Donna Culton MD, PhD
    Bart J. Currie MBBS, FRACP, DTM&H
    Chicky Dadlani MD
    Alexander Dane DO
    C. Ralph Daniel III MD
    Thomas Darling MD, PhD
    William Delaney MD
    Damian P. DiCostanzo MD
    Ncoza Dlova MD
    James Earls MD
    Libby Edwards MD
    Melissa K. Egge MD
    Charles N. Ellis MD
    Rachel Ellis MD
    David Elpern MD
    Nancy Esterly MD
    Stephen Estes MD
    E. Dale Everett MD
    Janet Fairley MD
    David Feingold MD
    Benjamin Fisher MD
    Henry Foong MBBS, FRCP
    David Foster MD, MPH
    Brian D. Foy PhD
    Michael Franzblau MD
    Vincent Fulginiti MD
    Sunir J. Garg MD, FACS
    Kevin J. Geary MD
    Lowell Goldsmith MD, MPH
    Sethuraman Gomathy MD
    Bernardo Gontijo MD, PhD
    Kenneth Greer MD
    Kenneth G. Gross MD
    Alan Gruber MD
    Nathan D. Gundacker MD
    Akshya Gupta MD
    Vidal Haddad MSC, PhD, MD
    Edward Halperin MD, MA
    Ronald Hansen MD
    John Harvey
    Rizwan Hassan MD
    Michael Hawke MD
    Jason E. Hawkes MD
    Peter W. Heald MD
    David G. Hicks MD
    Sarah Hocker DO
    Ryan J. Hoefen MD, PhD
    Li-Yang Hsu MD
    William Huang MD
    Sanjana Iyengar MD
    Alvin H. Jacobs MD
    Shahbaz A. Janjua MD
    Joshua J. Jarvis MD
    Kit Johnson
    Robert Kalb MD
    A. Paul Kelly MD
    Henry Kempe MD
    Loren Ketai MD
    Sidney Klaus MD
    Ashwin Kosambia MD
    Jessica A. Kozel MD
    Carl Krucke
    Mario E. Lacouture MD
    Joseph Lam MD
    Alfred T. Lane MD
    Edith Lederman MD
    Nahyoung Grace Lee MD
    Pedro Legua MD, PhD
    Robert Levin MD
    Bethany Lewis MD
    Sue Lewis-Jones FRCP, FRCPCH
    Taisheng Li MD
    Christine Liang MD
    Shari Lipner MD, PhD
    Jason Maguire MD
    Mark Malek MD, MPH
    Jere Mammino DO
    Ricardo Mandojana MD
    Lynne Margesson MD
    Thomas J. Marrie MD
    Maydel Martinez MD
    Ralph Massey MD
    Patrick McCleskey MD
    Karen McKoy MD
    Thomas McMeekin MD
    Josette McMichael MD
    Somchai Meesiri MD
    Joseph F. Merola MD
    Mary Gail Mercurio MD
    Anis Miladi MD
    Larry E. Millikan MD
    Dan Milner Jr. MD
    Zaw Min MD
    Stephanie Montero
    Alastair Moore MD
    Keith Morley MD
    Dean Morrell MD
    Samuel Moschella MD
    Taimor Nawaz MD
    Vic Newcomer MD
    John Nguyen MD
    Matilda Nicholas MD
    Thomas P. Nigra MD
    Steven Oberlender MD, PhD
    Maria Teresa Ochoa MD
    Art Papier MD
    Lawrence Parish MD
    Tanner Parrent MD
    Mukesh Patel MD
    Lauren Patty-Daskivich MD
    David Peng MD, MPH
    Robert Penne MD
    Nitipong Permpalung MD
    Doug Powell MD
    Harold S. Rabinovitz MD
    Christopher J. Rapuano MD
    Sireesha Reddy MD
    Angela Restrepo MD, PhD
    Bertrand Richert MD, PhD
    J. Martin Rodriguez, MD, FACP
    Theodore Rosen MD
    Misha Rosenbach MD
    Scott Schiffman MD
    Robert H. Schosser MD
    Glynis A. Scott MD
    Carlos Seas MD, MSc
    Deniz Seçkin MD
    Daniel Sexton MD
    Paul K. Shitabata MD
    Tor Shwayder MD, FAAP, FAAD
    Elaine Siegfried MD
    Gene Sienkiewicz MD
    Christye Sisson
    Mary J. Spencer MD, FAAP
    Sarah Stein MD
    William Van Stoecker MD
    Frances J. Storrs MD
    Erik J. Stratman MD
    Lindsay C. Strowd MD
    Erika Summers MD
    Belinda Tan MD, PhD
    Robert Tomsick MD
    Jenny Valverde MD
    Vishalakshi Viswanath MD
    Susan Voci MD
    Lisa Wallin ANP, FCCWS
    Douglas Walsh MD
    Ryan R. Walsh MD
    George Watt MD
    Clayton E. Wheeler MD
    Sally-Ann Whelan MS, NP, CWOCN
    Jan Willems MD, PhD
    James Henry Willig MD, MPH
    Karen Wiss MD
    Vivian Wong MD, PhD
    Sook-Bin Woo MS, DMD, MMSc
    Jamie Woodcock MD
    Stephen J. Xenias MD
    Lisa Zaba MD
    Vijay Zawar MD
    Bonnnie Zhang MD
    Carolyn Ziemer MD


Organizations

  • Am. Journal of Trop. Med & Hygiene
  • Armed Forces Pest Management Board
  • Blackwell Publishing
  • Bugwood Network
  • Centers For Disease Control and Prevention
  • Centro Internacional de Entrenamiento e Investigaciones Mèdicas (CIDEIM)
  • Dermatology Online Journal
  • East Carolina University (ECU), Division of Dermatology
  • International Atomic Energy Agency
  • Massachusetts Medical Society
  • Oxford University Press
  • Radiological Society of North America
  • Washington Hospital Center
  • Wikipedia
  • World Health Organization
ContentsSynopsisCodesLook ForDiagnostic PearlsDifferential Diagnosis & PitfallsBest TestsManagement PearlsTherapyReferencesView all Images (5)
Babesiosis
Print Captions OFF
Other Resources UpToDate PubMed

Babesiosis

Print Images (5)
Contributors: Peter Mariuz MD, William Bonnez MD, Mukesh Patel MD
Other Resources UpToDate PubMed

Synopsis

Babesiosis is a tick-borne zoonotic infection caused by protozoa of the genus Babesia. The major tick vector in the United States is Ixodes scapularis, which can also transmit Lyme disease, human granulocytic anaplasmosis (formerly known as human granulocytic ehrlichiosis), and Borrelia miyamotoi. Concomitant infections with these pathogens have been described. The main animal reservoir is the white-footed mouse. Babesia species, like Plasmodium, are obligate intracellular parasites of erythrocytes and may cause a malaria-like syndrome of fever and hemolysis.

Babesiosis due to Babesia microti is highly endemic in the following states: Connecticut, Massachusetts, New York, New Jersey, Rhode Island, Wisconsin, and Minnesota. Cases are also sporadically reported from many other states including Maine, Maryland, New Hampshire, and Vermont. Babesia duncani and a B. duncani-like species have been implicated in human babesiosis cases in the Pacific Northwest region of the United States. Sporadic cases have been noted in other parts of the United States. Babesia divergens occurs in Europe, and other species appear to cause sporadic disease in South America, Asia, and North Africa. Babesiosis can be transmitted via transfusion of contaminated blood products and, rarely, transplacentally.

Babesia species have a complex life cycle that includes asexual reproduction in mammalian host erythrocytes and sexual reproduction in tick vectors. The sporozoite form is injected into the skin of humans by a feeding tick. In erythrocytes, Babesia trophozoites reproduce by binary fission. Two or four merozoites are produced. If four remain close together, this merozoite tetrad form may be seen on Giemsa- or Wright-stained thin smears of blood (as the pathognomonic "Maltese cross"). The emergence of merozoites from erythrocytes causes cell lysis, and new infection of red blood cells ensues. Hemolytic anemia may develop accompanied by tissue hypoxia. Autoimmune hemolytic anemia may also occur.

Immunocompromised patients, particularly surgically or functionally asplenic individuals, are more likely to develop symptomatic disease and severe disease. Other risk factors for severe babesiosis include age greater than 50 years, cancer, human immunodeficiency virus infection, organ transplantation, hemoglobinopathy, chronic heart, lung or liver disease, and receipt of immunomodulatory agents.

The incubation period post-tick bite is 1-6 weeks but may be as long as 9 weeks in transfusion-related infection. Infections are asymptomatic or mild in most immunocompetent individuals. Most symptomatic infections are mild and self-limiting and present as a nonspecific viral-like illness characterized by gradual onset of fatigue, malaise, and fever and one or several of the following symptoms: chills, sweats, headache, myalgia, arthralgia, anorexia, cough, and nausea. There are few findings on physical exam except for fever and occasionally mild splenomegaly, hepatomegaly, or both. With the exception of petechiae and ecchymoses in severe infection, other skin manifestations are not observed.

Complications of more severe infection include acute respiratory failure, disseminated intravascular coagulation, congestive heart failure, lethargy, coma, and renal failure. Mortality rates of 6% to 9% have been reported in patients with severe infection. Most of these cases were in patients older than 50 and with significant comorbidities. Relapse of hemolytic anemia and symptoms is uncommon in treated and otherwise healthy patients, even though parasitemia may persist for over 1 year. Relapsing or persistent disease despite treatment may occur in immunosuppressed individuals.

Codes

ICD10CM:
B60.0 – Babesiosis

SNOMEDCT:
21061004 – Babesiosis

Look For

Subscription Required

Diagnostic Pearls

Subscription Required

Differential Diagnosis & Pitfalls

Other Tick-Borne Illnesses:
  • Human ehrlichiosis and anaplasmosis – No evidence of hemolysis; Giemsa- or Wright-stained peripheral blood smear may show intracytoplasmic morulae in polymorphonucleocytes or monocytes.
  • Rocky Mountain spotted fever – Look for the rash, which starts peripherally, can involve palms and soles, and may become petechial in nature. Hemolysis is unlikely to occur.
  • Lyme disease – Look for the presence of the typical rash, erythema chronicum migrans; no hemolysis.
  • Borrelia miyamotoi infection – Relapsing viral-like febrile illness can occur. Meningitis has been noted in immunocompromised patients. Occurs in areas endemic for Lyme disease in the United States; other cases have been noted in Japan and Russia. No hemolysis.
  • Tularemia – Look for a painful maculopapular lesion at the entry site that progresses to an ulcer and associated regional tender lymphadenopathy. The "typhoidal" form of tularemia presents without skin or lymph node involvement; no evidence of hemolysis.
Non Vector-Borne Illnesses:
  • Infectious mononucleosis – Look for atypical lymphocytosis, prominent sore throat, and lymphadenopathy.
  • Falciparum malaria – Travel / exposure history is important to determine whether the patient is at risk for malaria, babesiosis, or both. Careful examination of blood smears is essential. Tetrad forms are not seen with malaria. Babesia ring forms do not display hemozoin (brown pigment deposits) seen in older ring stages of Plasmodium falciparum.

Best Tests

Subscription Required

Management Pearls

Subscription Required

Therapy

Subscription Required

References

Subscription Required

Last Updated: 03/17/2017
Copyright © 2018 VisualDx®. All rights reserved.
Babesiosis
Captions OFF Print 5 Images
View all Images (5)
(with subscription)
Babesiosis : Chills, Fatigue, Fever, Headache, Nausea, Tick bite, Anorexia, Diaphoresis, Anemia, Myalgia
Lab image of Babesiosis
Blood smear showing various intraerythrocytic forms of babesia.
Copyright © 2018 VisualDx®. All rights reserved.