Hydatid Cyst in Emergency Service
Article Outline
To the Editor:
Hydatid cysts have a worldwide distribution and are most prevalent in sheep- and cattle-raising regions like Australia, South America, the Middle East, South Africa, Eastern Europe, and the Mediterranean region. Hydatid cysts may be found in almost any part of the body, resulting either from primary inoculation or via secondary spread.1
The disease is typically asymptomatic, and is commonly diagnosed alongside other illnesses.2 Sometimes symptoms can mimic other acute abdominal disorders and should be included in the differential diagnosis in emergency service patients. It can become symptomatic due to expansion, rupture or pyogenic infection. Rupture of the cyst is the most common complication, either internally or externally, followed by secondary infection, jaundice, and anaphylaxis.2
In this study, we analyzed demographic and clinical characteristics of the hydatid cyst patients who are admitted the emergency service due to complications of the hydatid cysts.
The medical records of patients admitted to the Department of Emergency at Ankara Numune Hospital between January 2006 and August 2008 with a final diagnosis of complicated hydatid cysts were reviewed for demographic information, admission symptoms, laboratory findings and evaluation techniques.
Ten patients (7 men, 3 women) with final diagnosis of complicated hydatid cyst included the study with mean age of 42.4 (range 17-75). All were from rural areas in Middle Anatolia. All of the patients had abdominal pain. While the pain was diffuse in the entire abdomen in 7 patients, it was located in the right upper quadrant in 3 patients. Patient's complaints were nausea (10 patients), vomiting (7), jaundice (4), ileus, (2), and urticaria (2). Physical examination revealed rebound tenderness in all patients, and 4 patients had fever. Nine of the patients had elevated leukocyte counts ranging from 12,000 to 20,000/μL.
Plain abdominal radiographs were normal in 7 patients. While 2 patients had air fluid levels of small intestine origin, 1 patient had an elevated right hemi-diaphragm, which was also observed on plain thorax films.
Ten patients underwent ultrasound examination. The primary findings on ultrasound were cystic lesions of the liver (10 patients), free intraperitoneal fluid (4 patients), and subdiaphragmatic abscess (1 patient). The cysts were located mainly in the right lobe (8 patients) based on the ultrasound examination.
After initial evaluation patients were referred to general surgery clinic for surgical intervention.
Hydatid cysts is a zoonotic human infection caused by the larval hydatid worm of echinococcus granulosus. Humans can become accidentally involved in the life cycle of the parasite by ingesting the eggs shed in the feces of the infected definitive host. Hydatid cysts are endemic in many countries where sheep, dogs, and humans live in close contact. There is variability in the incidence rates that have been reported.1, 2 In our study all of the patients come from rural areas of central Anatolia.
Hydatid cysts develop most frequently in the liver (65%), lungs (25%), and rarely in the spleen, kidneys, heart, bone, central nervous system, or other internal organs.1, 2
The symptoms of hydatid cysts may be related to local and mechanical effects depending on the location and nature of the cyst but hydatid fluid can be irritating, due to toxic reaction.3 In our group there were 2 patients with toxic reaction. Other patients presented with abdominal pain, icterus, ileus and fever.
Various incidence rates of direct rupture have been reported (1.75-8.6%). 2, 4, 5 The clinical signs and symptoms of hydatid cyst rupture are not always severe, but hydatid fluid can irritate, which can cause peritonitis as occurred in our series of patients, all of whom had acute abdominal signs. In the study of Patel and Butt,6 76% of the patients with ruptured hydatid cysts had abdominal pain. In our series, this rate was 100%. Thus, the clinical presentation of hydatid cyst rupture is not always silent. The severe clinical presentation and infrequency of hydatid cyst perforation has been held partially responsible for the misdiagnosis by the clinician.
The use of diagnostic imaging studies can be helpful. Ultrasound is widely used with an acceptable sensitivity and sensitivity for diagnosis and specificity of 90% with rupture.2
Compression and displacement of the biliary ducts are frequent. At the point of contact with a biliary duct, a rupture may occur. In frank rupture daughter vesicles and fragmented membranes escape into the biliary tree causing obstruction, cholangitis or septicemia.7
Mechanical bowel obstruction is an uncommon clinical presentation for hydatid disease, although intestinal obstruction due to rupture or fistulization of a hepatic, splenic, pancreatic, mesenteric, or retrovesical cysts into the gastrointestinal tract has been reported.4
In conclusion, in endemic areas, complicated hydatid cysts should be included in the differential diagnosis of acute abdomen. Ultrasound is an extremely helpful diagnostic aid.
References
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- Posttraumatic free intraperitoneal rupture of liver cystic Hydatid cysts : a case series and review of literature. Am J Surg. 2007;194:313–316
- Surgical management and long-term outcome of complicated liver hydatid cysts caused by Echinococcus granulosus. Surgery. 2005;137:312–316
- . The perforation problem in hydatid disease. Am J Trop Med Hyg. 2002;66:575–577
- Acute rupture of hydatid cysts in the peritoneum: 17 cases. Presse Med. 2004;33:378–384
- . Inadvertent rupture of an echinococcal cyst: case report and review of literature. Am J Med Sci. 2004;327:268–271
- Surgical management of spontaneous intrabiliary rupture of hydatid liver cysts. Surg Today. 2002;32:594–597
Funding and support: By Annals policy, all authors are required to disclose any and all commercial, financial, and other relationships in any way related to the subject of this article that might create any potential conflict of interest. The author has stated that no such relationships exist. See the Manuscript Submission Agreement in this issue for examples of specific conflicts covered by this statement.
PII: S0196-0644(09)00120-6
doi:10.1016/j.annemergmed.2009.01.035
© 2009 American College of Emergency Physicians. Published by Elsevier Inc. All rights reserved.
