Sparganosis of the Cauda Equina: A Rare Case of Lower Thoracic Cord Edema and Diagnostic Challenges.

Sparganosis is a rare parasitic infection caused by the larvae of Spirometra species, with spinal involvement being exceedingly uncommon. We present the case of a 46-year-old woman with progressive lower limb weakness, sensory deficits, and bowel and bladder dysfunction over a 3-month period. Initial magnetic resonance imaging revealed an abnormal intradural lesion from L2 to S2, along with thoracic spinal cord edema, raising suspicion for a spinal dural arteriovenous fistula (DAVF). After referral to our institution, further imaging ruled out DAVF, and findings suggested arachnoiditis and radiculitis of the lumbosacral nerve roots. The patient underwent a laminectomy, revealing inflamed arachnoid membranes and diffuse yellowish-whitish granulation tissue adherent to the cauda equina, which histopathological analysis confirmed as sparganosis. Postoperatively, the patient showed improved motor strength, although bowel and bladder dysfunction persisted. This case highlights the diagnostic challenges of spinal sparganosis, the need for early surgical intervention, and the importance of considering parasitic infections in endemic regions.