Primary hydatid disease of the spine: an unusual case.

Hydatid disease or hydatidosis caused by Echinococcus granulosus is the most widespread, serious human cestode infection in the world. Bone involvement is reported in 0.5-4% with spinal involvement reported in 50% of these cases. We report a case of this rare entity of an isolated primary hydatid cyst of the spine in a 15-year-old boy, who presented with progressive back pain for 8 months, lower extremity weakness and urinary incontinence for 3 months. Neurological examination was suggestive of upper motor neuron type of paraperesis grade 1/5 with complete sensory loss below T4 level. MRI of the spine showed multiple cystic extradural lesions at the T4-5 level with involvement of the paraspinal muscles. The patient underwent a T4-5 laminectomy, and a total excision of the multiple epidural and paraspinal cysts. The diagnosis of hydatid disease was confirmed on histopathology. Albendazole was started postoperatively. At 6 months follow-up the boy had no neurological deficit, was playful, active and walking. Postoperative MRI at 6 months showed no recurrence of the lesion. Analysis of the other reported cases is discussed with relevance to our case.