Neuroimaging observations linking neurocysticercosis and mesial temporal lobe epilepsy with hippocampal sclerosis.
OBJECTIVE
To test if chronic calcificed neurocysticercosis (cNCC) and hippocampal sclerosis occur more often than by chance ipsilateral to the same brain hemisphere or brain region in mesial temporal lobe epilepsy associated with hippocampal sclerosis (MTLE-HS) plus neurocysticercosis. This proof-of-concept would provide important evidence of a direct pathogenic relationship between neurocysticercosis and MTLE-HS.


METHODS
A cohort of 290 consecutive MTLE-HS surgical patients was studied. A test of proportions was used to analyze if the proportion of patients with a single cNCC lesion matching the same brain hemisphere or region of hippocampal sclerosis was significantly greater than 50%, as expected by the chance.


RESULTS
Neuroimaging findings of cNCC were observed in 112 (38.6%) of 290 MTLE-HS patients and a single cNCC lesion occurred in 58 (51.8%) of them. There were no differences in main basal clinical characteristics of MTLE-HS patients with single or multiple cNCC lesions. In patients with single cNCC lesions, the lesion matched the side in which hippocampal sclerosis was observed in 43 (74.1%) patients, a proportion significantly greater than that expected to occur by chance (p=0.008). Neurocysticercosis in temporal lobe was ipsilateral to hippocampal sclerosis in 85.0% of patients and accounted mostly for this result.


CONCLUSIONS
This work is a proof-of-concept that the association of neurocysticercosis and MTLE-HS cannot be explained exclusively by patients sharing common biological or socio-economic predisposing variables. Instead, our results suggest the involvement of more direct pathogenic mechanisms like regional inflammation, repetitive seizures or both. Neurocysticercosis within temporal lobes was particularly related with ipsilateral hippocampal sclerosis in MTLE-HS, a finding adding new contributions for understanding MTLE-HS plus cNCC or perhaps to other forms of dual pathology in MTLE-HS.
Center for Epilepsy Surgery (CIREP), Hospital das Clínicas de Ribeirão Preto, Department of Neurology, Ribeirão Preto School of Medicine, University of São Paulo, Ribeirão Preto, SP, Brazil; Basic Research and Advanced Investigations in Neurology (B.R.A.I.N.), Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil. Electronic address: mmbianchin@hotmail.com.
Marino M
MM
Bianchin
Center for Epilepsy Surgery (CIREP), Hospital das Clínicas de Ribeirão Preto, Department of Neurology, Ribeirão Preto School of Medicine, University of São Paulo, Ribeirão Preto, SP, Brazil; Department of Neurosciences and Behavior, Ribeirão Preto School of Medicine, University of São Paulo, Ribeirão Preto, SP, Brazil. Electronic address: tvelasco@fmrp.usp.br.
Tonicarlo R
TR
Velasco
Center for Epilepsy Surgery (CIREP), Hospital das Clínicas de Ribeirão Preto, Department of Neurology, Ribeirão Preto School of Medicine, University of São Paulo, Ribeirão Preto, SP, Brazil; Department of Radiology, Ribeirão Preto School of Medicine, University of São Paulo, Ribeirão Preto, SP, Brazil. Electronic address: lwichert@gmail.com.
Lauro
L
Wichert-Ana
Center for Epilepsy Surgery (CIREP), Hospital das Clínicas de Ribeirão Preto, Department of Neurology, Ribeirão Preto School of Medicine, University of São Paulo, Ribeirão Preto, SP, Brazil; Department of Radiology, Ribeirão Preto School of Medicine, University of São Paulo, Ribeirão Preto, SP, Brazil. Electronic address: ddaraujo17@gmail.com.
David
D
Araújo
Center for Epilepsy Surgery (CIREP), Hospital das Clínicas de Ribeirão Preto, Department of Neurology, Ribeirão Preto School of Medicine, University of São Paulo, Ribeirão Preto, SP, Brazil; Department of Neurosciences and Behavior, Ribeirão Preto School of Medicine, University of São Paulo, Ribeirão Preto, SP, Brazil. Electronic address: alexandreveriano@gmail.com.
Veriano
V
Alexandre
Center for Epilepsy Surgery (CIREP), Hospital das Clínicas de Ribeirão Preto, Department of Neurology, Ribeirão Preto School of Medicine, University of São Paulo, Ribeirão Preto, SP, Brazil; Basic Research and Advanced Investigations in Neurology (B.R.A.I.N.), Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil; Department of Neurosciences and Behavior, Ribeirão Preto School of Medicine, University of São Paulo, Ribeirão Preto, SP, Brazil. Electronic address: francisco.scornavacca@gmail.com.
Francisco
F
Scornavacca
Center for Epilepsy Surgery (CIREP), Hospital das Clínicas de Ribeirão Preto, Department of Neurology, Ribeirão Preto School of Medicine, University of São Paulo, Ribeirão Preto, SP, Brazil. Electronic address: sararosset@gmail.com.
Sara R
SR
Escorsi-Rosset
Center for Epilepsy Surgery (CIREP), Hospital das Clínicas de Ribeirão Preto, Department of Neurology, Ribeirão Preto School of Medicine, University of São Paulo, Ribeirão Preto, SP, Brazil; Department of Radiology, Ribeirão Preto School of Medicine, University of São Paulo, Ribeirão Preto, SP, Brazil. Electronic address: acsantos@fmrp.usp.br.
Antonio Carlos
AC
dos Santos
Center for Epilepsy Surgery (CIREP), Hospital das Clínicas de Ribeirão Preto, Department of Neurology, Ribeirão Preto School of Medicine, University of São Paulo, Ribeirão Preto, SP, Brazil; Neurosurgery Division, Department of Surgery and Anatomy, Ribeirão Preto School of Medicine, University of São Paulo, Ribeirão Preto, SP, Brazil. Electronic address: carlotti@fmrp.usp.br.
Carlos G
CG
Carlotti
Department of Neurosciences and Behavior, Ribeirão Preto School of Medicine, University of São Paulo, Ribeirão Preto, SP, Brazil. Electronic address: omtakay@fmrp.usp.br.
Osvaldo M
OM
Takayanagui
Center for Epilepsy Surgery (CIREP), Hospital das Clínicas de Ribeirão Preto, Department of Neurology, Ribeirão Preto School of Medicine, University of São Paulo, Ribeirão Preto, SP, Brazil; Department of Neurosciences and Behavior, Ribeirão Preto School of Medicine, University of São Paulo, Ribeirão Preto, SP, Brazil. Electronic address: sakamoto@fmrp.usp.br.
Américo C
AC
Sakamoto
D000328:Adult; D004833:Epilepsy, Temporal Lobe / Q000150:complications*; D005260:Female; D006624:Hippocampus / Q000473:pathology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D058069:Neglected Diseases; D020019:Neurocysticercosis / Q000150:complications*; D012189:Retrospective Studies; D012598:Sclerosis / Q000209:etiology / Q000473:pathology
Epileptogenesis; Immunology; Inflammation; Initial precipitating injury; Temporal lobe epilepsy