Background: Hydatidosis is a protozoal infestation which generally involves the liver and the lungs. Primary skeletal muscle hydatidosis without involving the thoracic and abdominal organs is extremely rare.
Methods: A 48-year-old farmer presented with a mass in the quadriceps muscle that had persisted for 10 years. Clinical and radiological investigations revealed a primary hydatid cyst of the vastus medialis of the quadriceps muscle. We did not find any visceral organ involvement. Wide excision was performed without destroying the cyst wall. Then 400 mg albendazole was given daily for 3 months postoperatively.
Results: At the 7th postoperative month, the patient was symptom-free, and the laboratory test results were in the normal ranges.
Conclusion: Primary muscular hydatidosis is a rare disease and should be kept in mind in the diagnostic work-up of a cystic mass of a skeletal muscle.