David Adelson MD
Christine Ahn MD
Sanah Ali MD
Carl Allen DDS, MSD
Brandon Ayres MD
Howard P. Baden MD
Yevgeniy Balagula MD
Robert Baran MD
Keira Barr MD
Sid Barsky 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
Mina Botros MD
Jeremy S. Boyd MD
Sarah Brenner MD
Robert A. Briggaman MD
Robert Brodell MD
Roman Bronfenbrener MD
Walter Brooks MD
Daniel Bryan MD
William Buckley MD
Philip Bulterys MD, PhD
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 E. Crutchfield III MD
Adriana Cruz MD
Donna Culton MD, PhD
Bart J. Currie MBBS, FRACP, DTM&H
Chicky Dadlani MD
Alexander Dane DO
Roxana Daneshjou MD
C. Ralph Daniel III MD
Thomas Darling MD, PhD
Steven Daveluy MD
William Delaney MD
Shreya Deoghare MD
Alex Derstenfeld
Damian P. DiCostanzo MD
Benedict F. DiGiovanni MD
Ncoza Dlova MD
Erin Doudt
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
Jennifer J. Findeis-Hosey MD
Benjamin Fisher MD
Robert Warne Fitch, MD
Henry Foong MBBS, FRCP
David Foster MD, MPH
Lindy P. Fox MD
Brian D. Foy PhD
Michael Franzblau MD
Vincent Fulginiti MD
Sunir J. Garg MD, FACS
Kevin J. Geary MD
Sharon Glick MD
Lowell Goldsmith MD, MPH
Sethuraman Gomathy MD
Bernardo Gontijo MD, PhD
Ayman Grada MD
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
Martha Hickman MD
David G. Hicks MD
Sarah Hocker DO
Ryan J. Hoefen MD, PhD
Li-Yang Hsu MD
Jennifer Huang MD
William W. Huang MD, MPH, FAAD
Eric F. Ingerowski MD
Sanjana Iyengar MD
Alvin H. Jacobs MD
Randy Jacobs MD, FAAD
Saagar Jadeja MD
Shahbaz A. Janjua MD
Joshua J. Jarvis MD
Noman Javed, MD
Beverly A. Johnson MD
Kit Johnson
Zachary John Jones MD
Harsimran Kaur MD
Robert Kalb MD
Katherine Kaproth-Joslin MD, PhD
Philip J. Katzman MD
A. Paul Kelly MD
Henry Kempe MD
Loren Ketai MD
Sidney Klaus MD
Sasank Konda, MD, FAAD
Ashwin Kosambia MD
Jessica A. Kozel MD
Carl Krucke
Mario E. Lacouture MD
Joseph Lam MD
Alfred T. Lane MD
Gerald S. Lazarus MD
Edith Lederman MD
Nahyoung Grace Lee MD
Ronald J. 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
Adam Lipworth MD
Jenna Lullo MD
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
Lynn McKinley-Grant 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
Nequesha Mohamed MD
Stephanie Montero
Alastair Moore MD
Martha Alejandra Morales-Sánchez MD
Keith Morley MD
Dean Morrell MD
Samuel Moschella MD
Surya N. Mundluru MD
Nicholas Erick Nacca MD
Rehan Naseemuddin MD
Taimor Nawaz MD
Vic Newcomer MD
John Nguyen MD
Matilda Nicholas MD, PhD
Thomas P. Nigra MD
Dylan Norton MD
Steven Oberlender MD, PhD
Maria Teresa Ochoa MD
Edward O'Keefe ND
Daniel C. Oppenheimer 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
Frank Johannes Plate MD, PhD
Miriam Pomeranz MD
Doug Powell MD
Harold S. Rabinovitz MD
Christopher J. Rapuano MD
Sireesha Reddy MD
Angela Restrepo MD, PhD
Cynthia Reyes-Barron MD
Bertrand Richert MD, PhD
J. Martin Rodriguez, MD, FACP
Theodore Rosen MD
Misha Rosenbach MD
Courtney Schadt 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
Daniel Siegel, MD
Elaine Siegfried MD
Gene Sienkiewicz MD
Christye Sisson
Jonathan Soh MD
Philip I. Song MD
Mary J. Spencer MD, FAAP
Lawrence B. Stack MD
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
Hensin Tsao MD, PhD
Richard P. Usatine MD
Jenny Valverde MD
Vishalakshi Viswanath MD
Susan Voci MD
Lisa Wallin ANP, FCCWS
Douglas Walsh MD
Ryan R. Walsh MD
George Watt MD
Erin X. Wei MD
Zachary Werle DO
Clayton E. Wheeler MD
Sally-Ann Whelan MS, NP, CWOCN
Danielle Wilbur MD
Jan Willems MD, PhD
Victoria L. Williams MD
James Henry Willig MD, MPH
Kelly Wilmas MD
Karen Wiss MD
Vivian Wong MD, PhD
Sook-Bin Woo MS, DMD, MMSc
Jamie Woodcock MD
Stephen J. Xenias MD
Nathaniel Yohannes
Lisa Zaba MD
Vijay Zawar MD
Bonnnie Zhang MD
Carolyn Ziemer MD
Barret Zimmerman MD
Jeffrey P. Zwerner MD, PhD
Organizations
American Academy of Dermatology
Am. Journal of Trop. Med & Hygiene
Armed Forces Pest Management Board
Blackwell Publishing
Broward Health Medical Center
Bugwood Network
Centers For Disease Control and Prevention
Centro Internacional de Entrenamiento e Investigaciones Mèdicas (CIDEIM)
Dermatology Associates of Concord
Dermatology Online Journal
East Carolina University (ECU), Division of Dermatology
International Atomic Energy Agency
Massachusetts Medical Society
NYU Department of Dermatology
Oregon Health & Science University (OHSU)
Oxford University Press
Radiological Society of North America
Washington Hospital Center
Wikipedia
World Health Organization
Echinococcosis, or hydatid disease, is a zoonotic parasitic (tapeworm) infection caused by the larval stage (metacestode) of species of the genus Echinococcus, mainly Echinococcusgranulosus (the northern biotype species is now recognized as Echinococcus canadensis) and Echinococcusmultilocularis, each of which leads to a different clinical presentation: cystic echinococcosis (CE) and alveolar echinococcosis (AE), respectively. A few other species, ie, Echinococcusortleppi, Echinococcusvogeli, and Echinococcusoligarthrus, are very rarely found in humans and will not be covered in this section.
CE is the most common cause of hydatid disease; it involves a definitive host (dog) and an intermediate herbivorous animal (sheep, cattle). Humans may accidentally become infected through ingestion of food or water contaminated with eggs or from contact with the fur of an infected dog. CE leads to slowly growing hepatic (70%) and/or pulmonary (20%) cystic lesions that can be asymptomatic for a variable time period (5-20 years). Cysts may be complicated by bacterial superinfection, cyst rupture, and anaphylactic shock.
AE involves wolves and dogs as definitive hosts and mice as intermediate hosts, with humans becoming infected through fecal-oral contact. AE is also a slowly advancing infection, although after a variable incubation period of 5-15 years, it differentiates itself from CE by producing multiple small vesicles infecting the liver initially, with subsequent metastatic spread to other organs (lungs, brain, bone, etc) in 20%-30% of cases. AE may be fatal if not treated.
CE has a nearly worldwide geographical distribution, although most cases reported in the United States are imported from European Mediterranean countries, the Russian Federation, China, Africa, Australia, and South America. AE is restricted to the northern hemisphere, with cases reported from Alaska and Canada in North America; Switzerland, Germany, and France in Europe; the tundra region of the Russian Federation; and the northern parts of China and Japan.
The initial phase of both CE and AE infection is asymptomatic. Cysts may grow slowly over months or even years. The infection may become symptomatic if the cysts either rupture or exert mass effect.
For liver involvement, abdominal pain and jaundice may occur with large cysts distending the liver capsule or compressing the biliary tree, while signs and symptoms of cholangitis or even anaphylaxis may present if cysts rupture.
For lung involvement, dyspnea can occur with large cyst(s) compressing lung parenchyma, while fever and cough productive of "salty" sputum may be the presenting signs of pulmonary cyst rupture.
The clinical presentation of the less common locations (ie, cardiac, renal, muscular, or subcutaneous) is usually caused by mass effect.
Some patients may develop immunologic manifestations, such as urticaria or eosinophilia, in response to leakage of cyst contents. This can occur at any point during the course of the infection.
Infection can be life-threatening in special situations (anaphylaxis) and in advanced cases, but by and large echinococcosis is a chronic condition.
Codes
ICD10CM: B67.90 – Echinococcosis, unspecified
SNOMEDCT: 74942003 – Echinococcosis
Look For
Subscription Required
Diagnostic Pearls
Subscription Required
Differential Diagnosis & Pitfalls
Echinococcosis differential diagnosis depends mainly on the location of the cyst(s).