Table 2. Case definition of CE in the article “Expert consensus for the diagnosis and treatment of cystic and alveolar echinococcosis in humans” published by WHO-IWGE in 2010.

A. Clinical criteria At least one of the following three: 1.A slowly growing or static cystic mass(es) (signs and symptoms vary with cyst location, size, type and number) diagnosed by imaging techniques. 2. Anaphylactic reactions due to ruptured or leaking cysts. 3. Incidental finding of a cyst by imaging techniques in asymptomatic carriers or detected by screening strategies.

B. Diagnostic criteria 1. Typical organ lesion(s) detected by imaging techniques (e.g. US, CT-scan, plain film radiography, MR imaging) 2. Specific serum antibodies assessed by highsensitivity serological tests, confirmed by a separate high specificity serological test 3.Histopathology or parasitology compatible with cystic echinococcosis (e.g. direct visualization of the protoscolex or hooklets in cyst fluid) 4.Detection of pathognomonic macroscopic morphology of cyst(s) in surgical specimens.

C. Possible versus probable versus confirmed case Possible case. Any patient with a clinical or epidemiological history, and imaging findings or serology positive for CE Probable case. Any patient with the combination of clinical history, epidemiological history, imaging findings and serology positive for CE on two tests. Confirmed case. The above, plus either (1) demonstration of protoscoleces or their components, using direct microscopy or molecular biology, in the cyst contents aspirated by percutaneous puncture or at surgery, or (2) changes in US appearance, e. g. Detachment of the endocyst in a CE1 cyst, thus moving to a CE3a stage, or solidification of a CE2 or CE3b, thus changing to a CE4 stage, after administration of ABZ (at least 3 months) or spontaneous.