A 61-year-old woman presented with low back pain associated with radiation to left lower limb since the past 1 year, with left foot drop since the past 1 month. Examination revealed wasting of the left lower limb with a foot drop. The remaining neurological examination was normal. Magnetic resonance imaging of the spine revealed diffusely bulky and multi-septated homogenous fluid-filled lesions (with signal intensity similar to cerebrospinal fluid [CSF]) in the intraspinal compartment from L3 to sacral vertebrae, causing extradural compression, and prevertebral and paravertebral locations (Figure 1). Contrast-enhanced computed tomography of the abdomen revealed similar cysts in the retroperitoneum, liver, and left psoas muscle. Serum ELISA was positive for Echinococcus IgG antibody (value-19.31; normal < 9), thus confirming the diagnosis of disseminated hydatidosis.
Hydatid disease is a parasitic infection caused by the larval form of Echinococcus granulosus.1 Humans are intermediate hosts who become infected by accidental consumption of infected food/water,2 with liver and lungs being the commonest sites of involvement.3 Bone involvement is rare, occurring in less than 2% cases, with spinal involvement occurring in half of those cases.3 The thoracolumbar spine is the common site of involvement, with involvement of the sacral spine being very rare.4 ELISA serology has a sensitivity of 80–100% for hepatic infections but only 25–56% for other organ involvement.5
In patients hailing from endemic regions and presenting with chronic low backache, with imaging suggestive of space-occupying lesions, hydatid disease should be considered in differential diagnosis. Early diagnosis and treatment lead to good clinical outcomes.
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