Parasites and Biliary stones

Echinococcosis ٤٧
parasites, as cestodes, is a major problem. Overall, cystic echinococcosis
serology may be improved by combining several defined antigens
(including synthetic peptides), and the design of new E granulosus
specific peptides that react with otherwise false-negative sera. Currently,
however, there is no standard, highly sensitive, and specific test available
for antibody detection in cases of the disease. Interleukin-4 detection may
be useful in the follow up of patients with cystic echinococcosis (Rigano
et al., 1999).
The diagnosis of Echinococcus multilocularis in intermediate and
aberrant hosts should be based on several criteria. These consist of the use
of macroscopic and histological examinations, including the morphology
and size of hooks on the protoscolices. In very small lesions additional
techniques may be necessary such as immunohistology with monoclonal
antibodies, DNA-hybridisation or PCR techniques (Eckert et al., 2001).
The most reliable means of diagnosis of Echinococcus in the definitive
host is by necropsy, as the worm burden can be estimated and parasites
collected for identification (Eckert, 1997).
Figure (14): Cystic echinococcosis: Lung cyst on chest radiograph (quoted from
Craig et al., 2007)