Diagnosis
Diagnosis of Hydatid disease is done using imaging techniques, examination of the cyst fluid and serological tests.
A routine chest x-ray may reveal a pulmonary cyst in the form of irregular lung masses. CT, MRI, and ultrasound findings are diagnostic. Hydatid sand and daughter cysts are characteristic findings. Simple Hydatid cysts are to be differentiated from simple benign cysts, abscesses or tumours.
Contents of hydatid cyst may be aspirated; the examination of this fluid is diagnostic. The imaging technique called ERCP (Endoscopic retrograde Cholangio-Pancreatography) is sometimes required.
Serologic tests include enzyme immunoassay, immunofluorescent assay, and indirect hemagglutination assay. Though their sensitivity vary it is important that the tests are performed. A complete blood count is also ordered for.
Casoni’s test is a blood test that can detect the presence of antibodies to the parasite; it is of historical value and has been abandoned due to a multitude of defects.
