Cysticercosis of the nervous system: less frequent clinical forms III- spinal cord forms

Abstract

The spinal forms of the cysticercosis of the nervous system are rather rare. It must be emphasized, however, as Henneberg 9 already did, that the incidence of these forms can not be precisely evaluated since the intraspinal structures are not systematically examined in the necropsies; besides, the spinal symptomatology frequently is overlooked or even masked by the outstanding and severe cerebral manifestations. Rocca16 , who has the greater series of cases in this field, remarks that the spinal cord forms are four times rarer than the cerebral ones, this proportion being much alike that of neoplasms. This finding, which concerns the cysticercosis of the nervous system in a general way, could be explained by the difference of nervous mass inside the skull and the spine. Harder to explain is the great disparity between the parenchymatous cysticercosis in the brain and the spinal cord; actually, in a survey of the literature we found only 7 cases of intramedullary cysts, while the extramedullary localization was reported in 35 cases (table 1).The parasite could follow two main routes in his way to the intraspinal space: the subarachnoidal migration, by passive transport in the cerebrospinal fluid current, or the hematogenic route. The first pathway, which would imply in the secondary feature of the spinal localization, could account for the perimedullary meningeal forms, but only the blood route could apparently explain the primary intramedullary localization of the cysticercus.

Spinal cord cysticercosis: neurosurgical aspects

“…6,8,9,13,20,26,33,36,37 Intradural spinal cysticercosis can be subdivided in leptomeningeal (subarachnoid) or intramedullary forms (parenchymal), the former being the most prevalent type of spinal parasitic infestation. In contrast to CNS lesions caused by the parasite Schistosoma mansoni, 41 in which the spinal cord is the principal site of damage, intramedullary involvement in cysticercosis is seldom observed, accounting for fewer than 20% of the intradural spinal cases.…”

“…In contrast to CNS lesions caused by the parasite Schistosoma mansoni, 41 in which the spinal cord is the principal site of damage, intramedullary involvement in cysticercosis is seldom observed, accounting for fewer than 20% of the intradural spinal cases. 9 Intramedullary spinal cord cysticerci, however, are being increasingly recognized by MR imaging. 33 Epidural cysts are rare.…”

Thoracic Intramedullary Cysticercosis. Two Case Reports.

“…[1][2][3][4][5][6][9][10][11][12][13][14]16,18,19,24,25,28) An analysis of 753 cases of neurocysticercosis found the incidence of spinal intramedullary cysticercosis to be 0.77%. 26) About 50% of patients harbored the parasite in other sites, such as the brain (30%) and muscles (25%).…”

“…Migration of larvae through the ventriculoependymal pathway has been postulated as another mechanism, although there is no convincing supporting evidence. 6) Spinal cysticercosis is present in 2-13% of patients with proven cranial disease. 25) Although concomitant intracranial involvement is usually found, but isolated spinal cysticercosis is known.…”

Breve comentário sobre a patogenia da cisticercose espinhal

“…Na cisticercose intramedular, propõe-se que o parasito possa instalar-se por disseminação hematogênica (arterial) 4 . 1 *), ou por migração ventrículo-ependimária 4 . Queiroz et al 10 analisaram criticamente a patogenia da cisticercose intramedular, com base em 16 casos coletados da literatura e um caso de sua experiência pessoal.…”