Cryptogenic epilepsy: an infectious etiology?
OBJECTIVE
Cryptogenic epilepsy, the group of epilepsy syndromes for which an etiology is unknown, comprises approximately 20% of all epilepsy syndromes. We selected patients in this subgroup of epilepsy and tested them for evidence of Toxoplasma gondii IgG antibodies by the enzyme-linked immunosorbent assay. T. gondii is found in up to 20% of the U.S. population forming dormant brain cysts in the latent bradyzoite form. We investigated the hypothesis that dormant T. gondii infection might be associated with cryptogenic epilepsy.


METHODS
We selected patients with cryptogenic epilepsies and tested them for evidence of T. gondii IgG antibodies by the enzyme-linked immunosorbent assay. A control group was also tested for comparison.


RESULTS
We have found a statistically-significant elevation of T. gondii antibodies among cryptogenic epilepsy patients as compared to controls [59% increase in optical density (OD), p = 0.013]. This association persisted after adjustment for subjects' gender and age in a multiple logistic regression model; however, it was no longer as statistically significant.


CONCLUSIONS
Our results suggest that chronic T. gondii infection with brain cysts may be a cause of cryptogenic epilepsy.
Stommel
E W
EW
Department of Medicine, Dartmouth Medical School, Hanover, New Hampshire 03755, USA.
Seguin
R
R
Thadani
V M
VM
Schwartzman
J D
JD
Gilbert
K
K
Ryan
K A
KA
Tosteson
T D
TD
Kasper
L H
LH
D000328:Adult; D000818:Animals; D000913:Antibodies, Protozoan / Q000032:analysis; D001927:Brain Diseases / Q000150:complications / Q000382:microbiology; D002908:Chronic Disease; D003560:Cysts / Q000150:complications; D004797:Enzyme-Linked Immunosorbent Assay; D004827:Epilepsy / Q000209:etiology* / Q000382:microbiology; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000032:analysis; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D014122:Toxoplasma / Q000276:immunology / Q000302:isolation & purification; D014123:Toxoplasmosis / Q000150:complications* / Q000382:microbiology
D000913:Antibodies, Protozoan; D007074:Immunoglobulin G