Pediatric Echinococcosis Workup

Updated: Dec 21, 2020
  • Author: Germaine L Defendi, MD, MS, FAAP; Chief Editor: Russell W Steele, MD  more...
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Laboratory Studies

Ultrasonography, chest radiography, CT scans, or MRI are imaging modalities that can detect findings suggestive of echinococcosis, especially in those patients with reported epidemiological risk factors. Serologic tests are then used to help confirm the diagnosis. If radiologic studies and epidemiology suggest echinococcosis, consider further evaluation when serology test results are negative.

The Centers for Disease Control and Prevention in Atlanta, Georgia provides the following types of serologic testing for humans: [12]

  • Indirect hemagglutination

  • Indirect fluorescent antibody

  • Enzyme immunoassay/enzyme-linked immunosorbent assay

Test sensitivities range from 60-95%. Liver cysts are more likely to yield positive serologic test results than pulmonary cysts. Positive test results are less likely with calcified or dead cysts and more likely with ruptured cysts.

False-positive serologic test results may occur in patients with other parasitic infections (e.g. cysticercosis) and in patients diagnosed with cancer or with immune dysfunction.

Antigen testing may be helpful if antibody test results are negative, although this modality is not available in the United States.

Stool evaluation for ova and parasites is generally not useful for diagnosis, but a loop-mediated isothermal amplification method (LAMP) for E. granulosus coprodetection in canines has been described. [13]


Imaging Studies

Ultrasonography is the imaging study of choice to diagnosis CE and AE. It is a noninvasive diagnostic tool and can ascertain hydatid cyst size. Ultrasonography may reveal irregular, heterogeneous, hypoechoic lesions, and calcified cysts. Ultrasonographic positive findings are then complemented or confirmed with computed tomography (CT) and/or magnetic resonance imaging (MRI). Liver cysts are commonly located in the hepatic right lobe and can be difficult to differentiate from abscesses or neoplasms. Liver cysts may be single or multiple.

Chest radiography may reveal cysts in the pulmonary fields, ranging from 1-20 cm in size. Pulmonary cysts do not calcify and they do not produce daughter cysts. Approximately one-third of patients with a positive finding on chest radiography, have definable hepatic cysts.