Corpora amylacea in temporal lobe epilepsy associated with hippocampal sclerosis

Abstract

-Hippocampal sclerosis (HS) is the commonest pathology in epileptic patients undergoing temporal lobe epilepsy surgery. Beside, there are an increased density of corpora amylacea (CA) founded in 6 to 63% of those cases. Objective: verify the presence of CA and the clinical correlates of their occurrence in a consective series of patients undergoing temporal surgery with diagnosis of HS. Method: We reviewed 72 hippocampus specimens from January 1997 to July 2000. Student's t test for independent, samples, ANOVA and Tukey test were performed for statistical analysis. Results: CA were found in 35 patients (49%), whose mean epilepsy duration (28.7 years) was significantly longer than that group of patients without CA (19.5 years, p= 0.001). Besides, when CA were found, duration was also significantly correlated with distribution within hippocampus: 28.7 years with diffuse distribution of CA, 15.4 with exclusively subpial and 17.4 years with distribution subpial plus perivascular (p= 0.001). Conclusion: Our findings corroborate the presence of CA in patients with HS and suggest that a longer duration of epilepsy correlate with a more distribution of CA in hippocampus.KEY WORDS: hippocampal sclerosis, corpora amylacea, temporal lobe epilepsy. Corpos amiláceos associados à esclerose hipocampal na epilepsia do lobo temporalRESUMO -A esclerose hipocampal (EH) é a patologia mais observada em lobectomias temporais de pacientes com epilepsia intratável. Além dos achados histopatológicos clássicos existe a presença de corpos amiláceos (CA) em até 60% dos hipocampos ressecados. Objetivo: Verificar a presença de corpos amiláceos em hipocampos de pacientes submetidos a cirurgia para tratamento de epilepsia e verificar se havia diferenças clínicas entre pacientes que apresentavam CA e aqueles em que eles não foram encontrados. Método: Foram revisados 80 hipocampos ressecados entre janeiro de 1997 a dezembro de 2000 e, posteriormente, os prontuários de 72 dos pacientes. Foi realizado o teste t de Student para amostras independentes, ANOVA e posteriormente o teste de Tukey. Resultados: Dos setenta e dois pacientes estudados, 40 eram homens (55,6%) e trinta e dois mulheres (44,4%). Trinta e cinco (48,6%) apresentavam CA e em trinta e sete (51,4%) não foram encontrados. Houve diferença estatisticamente significativa entre a média de tempo de evolução da epilepsia: o grupo com CA apresentava tempo maior de evolução (28,97 anos) em relação ao grupo que não apresentava CA (19,54 anos), com p= 0,001. Também observou-se diferença significativa quando foi comparada a localização de corpos amiláceos com o tempo de evolução da epilepsia: os pacientes com CA presentes difusamente no hipocampo apresentavam maior tempo de epilepsia (p= 0,001). Conclusão: Observamos que o nosso estudo confirma a presença de corpos amiláceos em hipocampos de pacientes com EH e sugerimos que quanto maior o período de epilepsia maior é a distribuição de CA no hipocampo PALAVRAS-CHAVE: esclerose hipocampal, corpora amylacea, epilepsia de lobo temporal.

Does abnormal glycogen structure contribute to increased susceptibility to seizures in epilepsy?

“…Presence of polyglucosans in neurons per se is possibly not the main factor leading to epilepsy, as neuronal PGBs are also found in patients with glycogen branching enzyme deficiency (glycogen storage disease type IV), which suffer from motor, sensory and autonomic deficits but not epilepsy (Robitaille et al, 1980). Inclusions of polyglucosans, named corpora amylacea in some old and new studies (for details on the nomenclature, see Cavanagh, 1999), have been frequently observed in cerebral astrocytes of patients suffering of several epileptic disorders and often correlated with seizure duration (Abel et al, 2010; Agari et al, 2012; Cherian et al, 2003; Chung and Horoupian, 1996; Das et al, 2011; Erdamar et al, 2000; Kakita et al, 2005; Kawamura et al, 2002; Nishio et al, 2001; Palmucci et al, 1982; Radhakrishnan et al, 2007; Radhakrishnan et al, 1999; Ribeiro Mde et al, 2003; Van Paesschen et al, 1997; Vanderhaeghen, 1971), although their occurrence has also been reported in various brain regions and even in other tissues either in the presence or in the absence of specific pathology (see Leel-Ossy, 1998). The aggregation of glycogen-like polymers is a complex and relatively unexplored phenomenon, which includes abnormal polyglucosans but also membrane-bound aggregates of normal β-glycogen (glycogenosomes) observed under various conditions such as lysosomal disorders and aging (Cavanagh and Jones, 2000).…”

Cuerpos amiláceos en la neocorteza de pacientes con epilepsia del lóbulo temporal y displasia cortical focal

“…En estudios previos 10,11,17 o series de pacientes 8,9,15,18,19,[21][22][23][24][25][26] han descrito la acumulación abundante de CoA en la neocorteza y en el hipocampo de pacientes con ELTFR y EH. En los hipocampos resecados, los CoA han sido observados en las siguientes áreas: CA1, CA3 y CA4, folium terminal y fascia dentada, y en menor grado en la corteza parahipocampal 8,15,25 .…”

“…Los grupos de Ribeiro et al y Abubakr et al comentan una asociación entre la duración de la epilepsia y la presencia de CoA, pero localizados en el hipocampo, sugiriendo que la formación de CoA se debe al proceso epileptogénico 22,23 . Otros autores consideran que la formación de los CoA está relacionada con los procesos celulares inducidos por un daño 27 , entonces las crisis pudieran contribuir también a su desarrollo, localizados estos en el hipocampo o en la neocorteza.…”

The presence of polyglucosan bodies in temporal lobe epilepsy: its role and significance

“…No significant differences were evident between the two groups in age of seizure onset, duration of seizure or surgical outcome. However Ribeiro et al 17 reviewed 72 hippocampus specimens with the features of MTS and corpora amylacea (PGBs) was found in 35 patients (49%). Apart from prolonged epilepsy duration (mean 28.7 years) in the group of patients with corpora amylacea (PGBs) there are no significant differences in other risk factors or clinical features.…”