Test Code MISC2MAYOECHNO Echinococcus Antibody, IgG, Serum
Useful For
Detection of antibodies to Echinococcus species, including Echinococcus multilocularis and Echinococcus granulosus
Method Name
Enzyme Immunoassay (EIA)
Reporting Name
Echinococcus Ab, IgG, SSpecimen Type
SerumSpecimen Required
Container/Tube:
Preferred: Serum gel
Acceptable: Red top
Specimen Volume: 0.5 mL
Specimen Minimum Volume
0.2 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Serum | Refrigerated (preferred) | 30 days | |
Frozen | 30 days |
Reject Due To
Gross hemolysis | Reject |
Gross lipemia | Reject |
Clinical Information
Echinococcosis, also referred to as hydatidosis or hydatid disease, is 1 of the 17 neglected tropical diseases recognized by the World Health Organization and affects over 1 million people worldwide. Echinococcus species are tapeworms or cestodes, and 2 main species infect humans: Echinococcus granulosus and Echinococcus multilocularis.
With respect to geographic distribution, E granulosus can be found worldwide but, more frequently, is found in rural grazing areas where dogs may feed on infected sheep or cattle carcasses. E multilocularis is largely localized to the northern hemisphere. The definitive hosts for E granulosus are dogs or other canids, while the definitive host for E multilocularis are foxes and, to a much lesser extent, canids. Echinococcus tapeworms reside in the small intestine of definitive hosts and release eggs that are passed in the feces and ingested by an intermediate host, typically sheep or cattle in the case of E granulosus or small rodents for E multilocularis. The eggs hatch in the small bowel, releasing an oncosphere that penetrates the intestinal wall and migrates through the circulatory system to various organs where it develops into a cyst that gradually enlarges producing protoscolicies and daughter cysts, which fill the interior. The definitive host becomes infected following ingestion of these infectious cysts. Humans become accidentally infected following ingestion of Echinococcus eggs.
In humans, E granulosus (cystic echinococcal disease) cysts typically develop in the lungs and liver, and the infection may remain silent or latent for years (5-20 years) prior to cyst enlargement and symptom manifestation. Symptomatic manifestations include chest pain, hemoptysis, and cough for pulmonary involvement and abdominal pain and biliary duct obstruction for liver infection. E multilocularis (alveolar echinococcal disease) infections manifest more rapidly than those of E granulosus and similarly to a rapidly growing, destructive tumor, resulting in abdominal pain and biliary obstruction. Rupture of cysts can produce fever, urticaria, and anaphylactic shock.
Diagnosis of echinococcal infections relies on characteristic finding by ultrasound or other imaging techniques and serologic findings. Fine-needle aspirates of cystic fluid may be performed; however, they carry the risk of cyst puncture and fluid leakage, which may potentially lead to severe allergic reactions. Importantly, infected individuals do not shed eggs in stool.
Reference Values
Negative
Reference values apply to all ages.
Interpretation
Negative:
The absence of antibodies to Echinococcus species suggests that the individual has not been exposed to this cestode. A single negative result should not be used to rule-out infection (see Cautions).
Equivocal:
Consider repeat testing on a new serum sample in 1 to 2 weeks.
Positive:
Results suggest infection with Echinococcus. False-positive results may occur in settings of infection with other helminths, or in patients with chronic immune disorders. Results should be considered alongside other clinical findings (eg, characteristic findings on imaging) and exposure history.
Method Description
Purified antigens are bonded to a microwell plate. Antibodies that are present in the patient samples attach themselves to the antigens and are determined during the second phase of the test by using enzyme-labelled antihuman antibodies (the conjugate). The enzyme converts the colorless substrate (urea peroxide/TMP) to a blue endproduct. The enzyme reaction is stopped by adding sulfuric acid. The colour of the mixture then switches from blue to yellow. A final measurement is carried out in a photometer at 450 nm using a reference wavelength of ≥620 nm.(Package insert: RIDASCREEN Echinococcus IgG. R-Biopharm AG: 09/2015)
Day(s) Performed
Tuesday, Thursday
Report Available
Same day/1 to 5 daysPerforming Laboratory

Test Classification
This test has been modified from the manufacturer's instructions. Its performance characteristics were determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
86682
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
ECHNO | Echinococcus Ab, IgG, S | 32171-1 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
64985 | Echinococcus Ab, IgG, S | 32171-1 |
Forms
If not ordering electronically, complete, print, and send a Microbiology Test Request (T244) with the specimen.