Cardiac Hydatid Cyst in a Cow: A Case Report on Morphological and Viability Assessment of Protoscoleces

Background: Cystic echinococcosis, caused by the larval stage of Echinococcus granulosus, is a zoonotic parasitic disease that affects humans and livestock. Although the liver and lungs are most commonly involved, cardiac hydatidosis is rare but may have serious pathological significance. Methods: A bovine heart showing external enlargement was submitted for pathological evaluation. Diagnostic ultrasonography and radiography were performed to locate cystic structures. Gross examination revealed one fluid-filled cyst attached to the epicardium and one calcified cyst within the myocardium. The cystic fluid was aspirated and examined microscopically. Using a ۰.۱% eosin stain, the viability of the protoscoleces was assessed—live forms remained unstained and motile, while dead forms stained red and immobile. Results: A total of ۱۰۱۲ protoscoleces were counted, of which ۹۳۱ (۹۲%) were viable and ۸۱ (۸%) were non-viable. The heart was visibly enlarged, and the presence of a calcified cyst indicated a chronic infection. The eosin exclusion test proved efficient for viability evaluation. Cardiac hydatid cysts, though uncommon in cattle, should be considered in the differential diagnosis of cardiac lesions. The high proportion of viable protoscoleces suggests a significant risk for transmission to definitive hosts if infected organs are improperly disposed of. Routine meat inspection and preventive measures are essential for controlling hydatidosis in endemic regions.

کلیدواژه ها:

Hydatid cyst ، Echinococcus granulosus ، bovine heart ، protoscoleces viability ، eosin staining