Hydatid disease of the spine: A rare case

Hydatid disease or hydatidosis is the most widespread zoonosis caused by Echinococcus granulosus. Liver and lungs are the most common sites. Bone involvement is rare and reported in 0.5%-4% with spinal involvement reported in 50% of these cases. We present a case of spinal hydatidosis in a 35-year-old male presenting with lower extremity weakness and numbness. Magnetic resonance imaging (MRI) of the spine showed multiple cystic lesions at the T9-T11 level with involvement of the paraspinal muscles. The lesion was seen intraspinal, intradural, intramedullary, and epidural. Radiological impression was aneurysmal bone cyst. The patient underwent laminectomy, and the excised cysts showed characteristic features of hydatid cyst (HC) on histopathology. The patient was started on antihelminthic therapy postoperatively. MRI is a diagnostic modality for HC, but the unusual location and absence of characteristic features can cause diagnostic difficulty. A high index of suspicion should be kept in patients residing in endemic areas and presenting with unusual cystic lesion of spine.