Laboratory Diagnosis of Cystic Hydatic Disease

Abstract

The main purpose of this article is to answer the questions about which test to perform for hydatic diagnosis and when. Several techniques for biologic diagnosis and follow-up of human cystic hydatidosis are reviewed. The specificity and sensitivity of immunologic reactions are reported. The differential diagnosis between Echinococcus granulosus and E. multilocularis is examined. The characteristics of the immunologic diagnosis according to the stage and the treatment of hydatidosis disease is discussed. Laboratory diagnosis of cystic hydatic disease is complementary to the clinical data. A judicious association of the usual techniques (indirect immunofluorescence assay, indirect hemagglutination assay, immunoelectrophoresis, co-electrophoresis with antigen 5 identification) confirms the diagnosis in 80% to 94% of hepatic hydatidosis cases and in 65% of pulmonary hydatidosis cases. Special techniques (enzyme-linked immunosorbent assay, Western blot, polymerase chain reaction) must be used for other localizations or when cysts are calcified. A serologic survey is necessary for the follow-up of operated medically treated patients. Despite poor standardization, purified antigens can distinguish between E. granulosus and E. multilocularis infections, although false-positive results are observed during other helminthiases, such as cysticerocosis.

An Easy and Efficient Method for Native and Immunoreactive Echinococcus granulosus Antigen 5 Enrichment from Hydatid Cyst Fluid

“…Diagnosis is usually based on symptomatology, epidemiological data, and the combined use of radiologic imaging and immunodiagnostic techniques [9]. Imaging is mostly useful to assess the cyst stage and to differentiate echinococcal cyst from benign cysts, cavitary tuberculosis, mycoses, abscesses, and benign or malignant neoplasms [10]. On the other hand, serological tests might offer advantages over radiological procedures, including early diagnosis of infection, early treatment for a more effective chemotherapy, and close follow-up monitoring programs [11].…”

Cystic Echinococcosis

“…It is therefore important to remember that a negative serologic test result does not exclude the presence of cystic echinococcosis. Serology is positive in around 80% to 94% of hepatic echinococcosis cases and 65% of pulmonary cases (23).…”

“…These methods have various levels of sensitivity and somewhat poor specificity, especially in patients with other helminthic infections. For many assays, the antigen material used for testing is a crude or purified preparation from animal liver hydatid cysts and is likely a significant source of variability in test performance (6,23).…”

Seronegative, complicated hydatid cyst of the lung: A case report

“…Factors such as cyst size, stage, location and patient characteristics have been suggested to affect the test results [13]. A negative serological test normally does not rule out CE [14]. IHA test for serum antibodies for E. granulosis is positive in approximately 50% of patients with pulmonary CE [15].…”