A Rare Case of Large Hydatid Cyst at Atypical Location: Case Study

Hydatiddisease also know as Echinococcosis and caused by Echinococcus granulosus and Echinococcus multilocularis, which cause Cystic echinococcosis (CE) and alveolar echinococcosis (AE). Most common site for Hydatid cyst is liverandlungor both sites. But it can grow at unusual sites like bone, muscle, except hair and nail. Present case was a 65 years male who came with complaints of gradually increasing swelling of left thigh for last 9 months. There was recent onset of pain while changing posture from sitting to standing. USG (Ultrasonography) showed a hypoechoic lesion extending from groin to mid-thigh. MRI showed multiple round to oval cystic mass lesionsin adductor muscle of left thigh with thin walled daughter cysts suggestive of Hydatid disease. Hydatid Serology was negativewith no eosinophilia on hemogram. Albendazole was started 2 weeks preoperatively. Patient underwent enbloc excision and Histopathology report conformed the diagnosis hydatid disease. Patient was put on albendazole 400 mg for 14 weeks. Post-operative follow-up for one year showed no recurrence.

Conclusion: Hydatid cyst of a thigh muscle is a very rare condition and its diagnosis would require a high index of suspicion. The results of hydatid serology in cases of Musculo-skeletal organs could be negative but radiology imaging of the thigh including ultrasound scan, computed tomography scan and magnetic resonance imaging scan would tend to demonstrate features of the lesion that would be suggestive of Echinococcus disease of the thigh. Treatment of the disease does involve utilization of albendazole treatment for many weeks and complete excision of the lesion taking care to avoid spillage of the contents of the cyst.