Cerebrospinal Fluid Changes in Experimental Model of Extraparenchymal Neurocysticercosis: preliminary results

Introduction: Neurocysticercosis (NCC) is the most common parasitic disease affecting the CNS and is considered a public health problem in many countries around the world, including Brazil. The cerebrospinal fluid (CSF) changes provoked by the disorder in humans are well defined in literature and were first described in 1940 by Lange. These modifications include pleocytosis, hyperproteinorrachia and eosinophilia. The majority of the experimental models of NCC published are focused on the parenchymal form of the disease. Few models studied the extraparenchymal form or analyzed the CSF parameters. Objective: To analyze the temporal modifications in the CSF of rabbits after the experimental induction of extraparenchymal NCC. Method: We included 14 male rabbits in this study. Each animal underwent a suboccipital injection of 50 cysts of T. crassiceps into the cisterna magna. Just before the inoculation, CSF samples were collected (sham). The animals were observed for 6 months, with monthly suboccipital punctures for CSF sample collection. Cellularity and protein concentration changes were analyzed throughout the observation period. Results: The initial cell counting average was only 1 (±0.88) cell/μL, raising to 1138.9 (±624.1) cells/μL in the first month and then dropping to 17.2 (±14.4) cells/μL in the sixth month. The differential analysis proved that, after the inoculation, lymphocytes were the most common cells in the CSF (85.1%, ±14.6). A similar pattern was identified with the proteinorrachia: an initial average of 25.8 (±8.3) mg/dL, increasing to 66.5 (±22.5) mg/dL one month later and then gradually decreasing to 40.2 (±15.6) mg/dL in the last month. Conclusion: It was possible to identify a substantial increase in cellularity and protein concentration in the CSF after the induction of NCC in rabbits, followed by a gradual fall over the remaining months. These variations are comparable to the findings in humans. The authors are currently giving continuity to this study, and stronger data will be released in future publications.