Close
New

Medscape is available in 5 Language Editions – Choose your Edition here.

 

Hydatid Cysts

  • Author: Imad S Dandan, MD; Chief Editor: BS Anand, MD  more...
 
Updated: Aug 19, 2014
 

Background

Hydatid disease is a parasitic infestation by a tapeworm of the genus Echinococcus. It is not endemic in the United States, but the change in the immigration patterns and the marked increase in transcontinental transportation over the past 4 decades have caused a rise in the profile of this previously unusual disease throughout North America. This has led to the necessity for physicians to be more aware of its clinical features, diagnosis, and management.

Next

Pathophysiology

Human echinococcosis is a zoonotic infection caused by the tapeworm of the genus Echinococcus. Of the 4 known species of Echinococcus, 3 are of medical importance in humans. These are Echinococcus granulosus, causing cystic echinococcosis (CE); Echinococcus multilocularis, causing alveolar echinococcosis (AE); and Echinococcus vogeli. E granulosus is the most common of the three. E multilocularis is rare but is the most virulent, and E vogeli is the most rare.

Previous
Next

Epidemiology

Frequency

United States

Despite an increase in its occurrence, echinococcosis remains a very rare disease (< 1 case per 1 million inhabitants) in the continental United States. Northern Alaska has endemic areas of E granulosus, but the frequency of infection remains low (< 1 case per 100,000 inhabitants).

International

Echinococcosis is also unusual in northern Europe. The endemic areas are the Mediterranean countries, the Middle East, the southern part of South America, Iceland, Australia, New Zealand, and southern parts of Africa; the latter 5 are intensive endemic areas. Central Asia, particularly China, is also an endemic area.[1, 2] The incidence of CE in endemic areas ranges from 1-220 cases per 100,000 inhabitants, while the incidence of AE ranges from 0.03-1.2 cases per 100,000 inhabitants, making it a much more rare form of echinococcosis. An epidemiological study of cyctic echinococcosis in Romania emphasized the need for improved preventive measures.[3] Infestation with E vogeli is the most rare form of echinococcosis and is reported mainly in the southern parts of South America.

Mortality/Morbidity

See the list below:

  • Morbidity is usually secondary to free rupture of the echinococcal cyst (with or without anaphylaxis), infection of the cyst, or dysfunction of affected organs. Examples of dysfunction of affected organs are biliary obstruction, cirrhosis, bronchial obstruction, renal outflow obstruction, increased intracranial pressure secondary to mass, and hydrocephalus secondary to cerebrospinal fluid outflow obstruction.
  • In CE, mortality is secondary to anaphylaxis, systemic complications of the cysts (eg, sepsis, cirrhosis, respiratory failure, or operative complications.
  • In clinical cases of AE, the mortality rate is 50-60%. This figure reaches 100% for untreated or poorly treated AE. Sudden death has been reported with AE in asymptomatic patients (autopsy diagnosis).

Race

See the list below:

  • Because of the restricted geographic distribution of the echinococcal worms, persons of certain races are affected more commonly than others; however, the parasite has the capability of infecting persons of all races equally.

Sex

See the list below:

  • No sexual predilection is recognized.

Age

See the list below:

  • The cysts grow slowly, and a cyst is rarely diagnosed during childhood or adolescence unless the brain is affected.
  • CE is a disease of younger adults, with an average age at diagnosis of 30-40 years.
  • AE is a disease of older adults, with an average age at diagnosis of older than 50 years.
Previous
 
 
Contributor Information and Disclosures
Author

Imad S Dandan, MD Chief of Trauma Section, Scripps Memorial Hospital La Jolla, California

Imad S Dandan, MD is a member of the following medical societies: American Association for the Surgery of Trauma, American College of Surgeons, American Medical Association, California Medical Association, American Trauma Society, Society of Critical Care Medicine

Disclosure: Nothing to disclose.

Coauthor(s)

Assaad M Soweid, MD, FACG, FASGE Associate Professor of Clinical Medicine, Endosonography and Advanced Therapeutic Endoscopy, Director, Endoscopy-Bronchoscopy Unit, Division of Gastroenterology, Department of Internal Medicine, American University of Beirut Medical Center, Lebanon

Assaad M Soweid, MD, FACG, FASGE is a member of the following medical societies: American College of Gastroenterology, American College of Physicians, American College of Physicians-American Society of Internal Medicine, American Medical Association

Disclosure: Nothing to disclose.

Firass Abiad, MD Fellow in Minimally Invasive Surgery, Department of Surgery, University of Tennessee

Disclosure: Nothing to disclose.

Specialty Editor Board

Francisco Talavera, PharmD, PhD Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Received salary from Medscape for employment. for: Medscape.

Chief Editor

BS Anand, MD Professor, Department of Internal Medicine, Division of Gastroenterology, Baylor College of Medicine

BS Anand, MD is a member of the following medical societies: American Association for the Study of Liver Diseases, American College of Gastroenterology, American Gastroenterological Association, American Society for Gastrointestinal Endoscopy

Disclosure: Nothing to disclose.

Additional Contributors

Ann Ouyang, MBBS Professor, Department of Internal Medicine, Pennsylvania State University College of Medicine; Attending Physician, Division of Gastroenterology and Hepatology, Milton S Hershey Medical Center

Disclosure: Nothing to disclose.

References
  1. Wang K, Zhang X, Jin Z, Ma H, Teng Z, Wang L. Modelling and analysis of the transmission of echinococcosis with application to Xinjiang Uygur Autonomous Region of China. J Theor Biol. 2013 May 10. [Medline].

  2. Torgerson PR. The emergence of echinococcosis in central Asia. Parasitology. 2013 May 10. 1-7. [Medline].

  3. Moldovan R, Neghina AM, Calma CL, Marincu I, Neghina R. Human cystic echinococcosis in two south-western and central-western Romanian counties: A 7-year epidemiological and clinical overview. Acta Trop. 2012 Jan. 121(1):26-9. [Medline].

  4. Siracusano A, Delunardo F, Teggi A, Ortona E. Host-parasite relationship in cystic echinococcosis: an evolving story. Clin Dev Immunol. 2012. 2012:639362. [Medline]. [Full Text].

  5. Kapan S, Turhan AN, Kalayci MU, Alis H, Aygun E. Albendazole is not effective for primary treatment of hepatic hydatid cysts. J Gastrointest Surg. 2008 May. 12(5):867-71. [Medline].

  6. Ochieng'-Mitula PJ, Burt MD. The effects of ivermectin on the hydatid cyst of Echinococcus granulosus after direct injection at laparotomy. J Parasitol. 1996 Feb. 82(1):155-7. [Medline].

  7. Mamarajabov S, Kodera Y, Karimov S, Abdiev S, Sabirov B, Krotov N, et al. Surgical Alternatives for Hepatic Hydatid Disease. Hepatogastroenterology. 2011 Oct 12. 58(112):[Medline].

  8. Elsebaie SB, El-Sebae MM, Esmat ME, Nasr MM, Kamel MM. Modified endocystectomy versus pericystectomy in echinococcus granulosus liver cysts: a randomized controlled study, and the role of specific anti-hydatid IgG4 in detection of early recurrence. J Egypt Soc Parasitol. 2006 Dec. 36(3):993-1006. [Medline].

  9. Filippou D, Tselepis D, Filippou G, Papadopoulos V. Advances in liver echinococcosis: diagnosis and treatment. Clin Gastroenterol Hepatol. 2007 Feb. 5(2):152-9. [Medline].

  10. Flisser A. Larval cestodes. Collier L, Balows A, Sussman M, eds. Topley and Wilson's Microbiology and Microbial Infections. Parasitology. 9th ed. New York, NY: Oxford University Press; 1998. Vol 5: 539-60.

  11. Gargouri M, Ben Amor N, Ben Chehida F, Hammou A, Gharbi HA, Ben Cheikh M, et al. Percutaneous treatment of hydatid cysts (Echinococcus granulosus). Cardiovasc Intervent Radiol. 1990 Jun-Jul. 13(3):169-73. [Medline].

  12. Guidelines for treatment of cystic and alveolar echinococcosis in humans. WHO Informal Working Group on Echinococcosis. Bull World Health Organ. 1996. 74(3):231-42. [Medline]. [Full Text].

  13. Heath DD. Immunology of echinococcus infections. Thompson R, Lymbery AJ, eds. Echinococcus and Hydatid Disease. Wallingford, Oxon: CAB International; 1995. 183-200.

  14. Kjossev KT, Losanoff JE. Hydatid cysts of the liver: TN(R)C classification. Int Surg. 1998 Oct-Dec. 83(4):311-3. [Medline].

  15. Liu D, Lightowlers MW, Rickard MD. Evaluation of a monoclonal antibody-based competition ELISA for the diagnosis of human hydatidosis. Parasitology. 1992 Apr. 104 ( Pt 2):357-61. [Medline].

  16. Liu YH, Wang XG, Chen YT, Yao YQ. Computer tomography of liver in alveolar echinococcosis treated with albendazole. Trans R Soc Trop Med Hyg. 1993 May-Jun. 87(3):319-21. [Medline].

  17. Polo JR, Garcia-Sabrido JL. Sclerosing cholangitis associated with hydatid liver disease. Arch Surg. 1989 May. 124(5):637. [Medline].

  18. Schröder R, Robotti G. New aspects in the management of alveolar echinococcosis involving the liver. World J Surg. 1986 Dec. 10(6):968-73. [Medline].

  19. Tan A, Yakut M, Kaymakçioglu N, Ozerhan IH, Cetiner S, Akdeniz A. The results of surgical treatment and percutaneous drainage of hepatic hydatid disease. Int Surg. 1998 Oct-Dec. 83(4):314-6. [Medline].

  20. Taylor BR, Langer B. Current surgical management of hepatic cyst disease. Adv Surg. 1997. 31:127-48. [Medline].

  21. Taylor DH, Morris DL. In vitro culture of Echinococcus multilocularis: protoscolicidal action of praziquantel and albendazole sulphoxide. Trans R Soc Trop Med Hyg. 1988. 82(2):265-7. [Medline].

  22. Todorov T, Mechkov G, Vutova K, Georgiev P, Lazarova I, Tonchev Z, et al. Factors influencing the response to chemotherapy in human cystic echinococcosis. Bull World Health Organ. 1992. 70(3):347-58. [Medline].

  23. von Sinner WN. New diagnostic signs in hydatid disease; radiography, ultrasound, CT and MRI correlated to pathology. Eur J Radiol. 1991 Mar-Apr. 12(2):150-9. [Medline].

  24. Williams JF, Perez Esandi MV, Oriol R. Evaluation of purified lipoprotein antigens of Echinococcus granulosus in the immunodiagnosis of human infection. Am J Trop Med Hyg. 1971 Jul. 20(4):575-9. [Medline].

 
Previous
Next
 
 
 
 
All material on this website is protected by copyright, Copyright © 1994-2016 by WebMD LLC. This website also contains material copyrighted by 3rd parties.