To the editor:
The work by Oliveira, et al. published in the journal last July addressed once
again the interesting question regarding the relationship of chronic
calcifications suggestive of neurocysticercosis (NC) and the development of
mesial temporal lobe epilepsy with hippocampal sclerosis (MTE-HS)11 Oliveira MCB, Martin MGM, Tsunemi MH, Vieira G,
Castro LHM. Small calcified lesions suggestive of
neurocysticercosis are associated with mesial temporal
sclerosis. Arq Neuropsiquiatr. 2014;72(7):510-6.
http://dx.doi.org/10.1590/0004-282X20140080
https://doi.org/10.1590/0004-282X2014008...
. The publication
concluded that there is a higher incidence of brain calcifications
suggestive of NC in patients with MTS-HS, when compared to a control of
other epilepsy syndrome populations. This conclusion corroborates similar
findings published by different groups previously22 Velasco TR, Zanello PA, Dalmagro CL, Araújo
Junior D, Santos AC, Bianchin MM et al. Calcified
cysticercotic lesions and intractable epilepsy: a cross
sectional study of 512 patients. J Neurol Neurosurg
Psychiatry. 2006;77(4):484-8.
http://dx.doi.org/10.1136/jnnp.2005.078675
https://doi.org/10.1136/jnnp.2005.078675...
. Since neurocysticercosis is largely
implicated as the cause of epilepsy in the developing world, including
Brazil, our group considered this work very important as the catalyst for
future discussions and research in this subject. As pointed out in the
discussion session, many questions are still to be answered: What is the
potential mechanism involved in the development of MTS-HS in these patients?
More importantly, who is at increased risk of developing MTS-HS from NC
infections? The predominant incidence of calcifications in the ipsilateral
temporal lobe points towards a possible local mechanism, as mentioned in the
article. In addition, repeated clinical and sub-clinical seizures, triggered
during the acute NC phase appear as potential sources of initial
precipitating injuries. Recent abstract presented by our group from
Fortaleza-Brazil at the 2013 American Academy of Neurology meeting pointed
out an increased incidence of white matter disease and lacunar strokes in
patients with calcified lesions suggestive of NC, which also raises the
hypothesis that local inflammatory reactions may be associated to these
findings33 Gondim FA, Sales PM, Silva M, Gomes A, Lima JW,
Bezerra G et al. Increased prevalence of lacunar strokes and
severe white matter disease in patients with
neurocysticercosis. Neurol. 2013;80(meeting abstracts
1).. It also
revealed a prevalence of calcifications suggestive of NC of 2.7% in a
general population who underwent brain CT scan for several different
reasons, not only convulsions. Nevertheless, as stated by Oliveira et al.,
there is still a possibility that the calcifications identified by CT brain
are not from NC. The current criteria developed by Del Brutto et al.44 Garcia HH, Del Brutto OH. Neurocysticercosis: updted
concepts about an old disease. Lancet Neurol.
2005;4(10):653-61.
http://dx.doi.org/10.1016/S1474-4422(05)70194-0
https://doi.org/10.1016/S1474-4422(05)70...
addresses potential
active forms of NC, but we lack a more precise way of identifying
intra-cerebral calcifications as “incomplete” or
“halted” forms of infection by Taenia solium.
As suggested, adding epidemiological criteria, such as contact with pigs or
living in rural areas, might help. Serological and pathological studies
would add to this quest. The answers for these questions will help
identifying why some patients do not appear to develop the active form of
NC, while others suffer from acute and late effects of this disease.
References
-
1Oliveira MCB, Martin MGM, Tsunemi MH, Vieira G, Castro LHM. Small calcified lesions suggestive of neurocysticercosis are associated with mesial temporal sclerosis. Arq Neuropsiquiatr. 2014;72(7):510-6. http://dx.doi.org/10.1590/0004-282X20140080
» https://doi.org/10.1590/0004-282X20140080 -
2Velasco TR, Zanello PA, Dalmagro CL, Araújo Junior D, Santos AC, Bianchin MM et al. Calcified cysticercotic lesions and intractable epilepsy: a cross sectional study of 512 patients. J Neurol Neurosurg Psychiatry. 2006;77(4):484-8. http://dx.doi.org/10.1136/jnnp.2005.078675
» https://doi.org/10.1136/jnnp.2005.078675 -
3Gondim FA, Sales PM, Silva M, Gomes A, Lima JW, Bezerra G et al. Increased prevalence of lacunar strokes and severe white matter disease in patients with neurocysticercosis. Neurol. 2013;80(meeting abstracts 1).
-
4Garcia HH, Del Brutto OH. Neurocysticercosis: updted concepts about an old disease. Lancet Neurol. 2005;4(10):653-61. http://dx.doi.org/10.1016/S1474-4422(05)70194-0
» https://doi.org/10.1016/S1474-4422(05)70194-0
Publication Dates
-
Publication in this collection
Feb 2015
History
-
Received
01 Oct 2014 -
Received
08 Oct 2014 -
Accepted
28 Oct 2014