A Case of Intradural-Extramedullary Form of Primary Spinal Cysticercosis Misdiagnosed as an Arachnoid Cyst

Abstract

We describe a rare case of intradural-extramedullary primary spinal cysticercosis. A 42-year-old man visited our institute for lower back pain. He denied having consumed raw meet. Magnetic resonance (MR) images revealed an intradural pure cystic mass at the L3-L4 level. A radiologic diagnosis of spinal arachnoid cyst was established. Three years later, he complained of aggravated back pain, and follow-up MR examination showed a markedly expanded cyst, occupying the subarachnoid space from the T11 to the S1 level. L2 hemilaminectomy was performed, and a yellowish infected cyst bulged out through the dural opening. The cyst was removed en bloc. The histopathological findings of the cyst were consistent with parasitic infection. Serum enzyme-linked immunosorbent assay (ELISA) confirmed the presence of spinal cysticercosis. As there was no intracranial lesion, the final diagnosis was primary spinal cysticercosis, which is very rare. MR imaging is a sensitive diagnostic tool for detecting cystic lesions in the spine; however, it is difficult to distinguish cysticercosis from non-infectious cysts such as an arachnoid cyst without using gadolinium enhancement. Clinicians treating spinal cysts with an unusual clinical course should include cysticercosis as a differential diagnosis. We recommend contrast-enhanced MR imaging and serum ELISA in the diagnostic work-up of such cases.

Intradural spinal neurocysticercosis: case illustration

“…The imaging study of choice for the detection of spinal lesions is MRI, however, it is difficult to detect small calcifications (5,7,15). MRI findings vary depending on the stages of the disease.…”

“…The NCC was first described by Paranoli in 1550, and its causative agent, the Taenia solium, was recognized by Leuckart y Kuchenmeister in the 19th century (6,12,13). Spinal involvement is rare, and it has been subdivided in extradural, intradural-extramedullary and intramedullary, being the most rare form of presentation, accounting for <20% of all cases (1,4,7,(14)(15)(16). Spinal NCC occurs frequently with a diagnosis of intracranial NCC, these cases are approximately 75%, however, isolated cases of spinal NCC are uncommon (6,11,16).…”

“…The diagnosis of NCC is made from neuroimaging, analysis of CSF and the detection of antibodies in serum (7,15,16). Several criteria have been proposed to facilitate its diagnosis; the major criteria include neuroimaging findings suggestive of NCC (cystic lesions or large calcifications), detection of anticystic antibodies by immunoblotting and resolution of cystic lesions after treatment with albendazole or praziquantel.…”

“…Neurocystecircosis -NCC is unusual form of cysticercosis (1)(2)(3)(4)(5)(6), which can be categorized according to its main CNS involvement as: parenchymal, leptomeningal, intraventricular or spinal, according to the location of the lesions. Spinal NCC accounts for about 0.7 to 0.85% of all cases, and most of these are accompanied by concomitant intracranial involvement (2,(7)(8)(9); it also may occur with extra-spinal involvement (vertebral) or intraspinal (intradural, extramedullary or intramedullary) (4), being the extramedullary-intradural form the most common, with an incidence of almost 80% of the spinal forms (5).…”

Case report of an epidural cervical Onchocerca lupi infection in a 13-year-old boy

“…While isolated spinal cysticercosis without intracranial involvement is rare, patients with spinal echinococcosis present more often with primary spinal infection. 1,3,5,[7][8][9][10][11][12][13][14][17][18][19][20]22 In a recent review of 467 cases of spinal echinococcosis by Neumayr et al, 13 17.9% were primary spinal infections without intracranial involvement.…”