Neuropsychological and positron emission tomography correlates in idiopathic environmental intolerances.
OBJECTIVE
It has been hypothesized that people with subjective hypersensitivity to chemicals may indeed suffer from neuronal damage due to widely distributed environmental toxins and that such deficits of diagnostic importance can be demonstrated with the help of functional neuroimaging even in single cases. In this study, a small group of well-characterized patients with idiopathic environmental intolerance were examined in order to identify such changes.


METHODS
Twelve patients with idiopathic environmental intolerance were investigated neuropsychologically and underwent cerebral F-18 fluorodeoxyglucose (F-18 FDG) positron emission tomography (PET). The imaging results were compared with findings from 17 healthy controls.


RESULTS
Six patients showed deficits in verbal learning and memory, three of them also had a reduced information processing speed. In the individual analyses, 11 patients showed normal cerebral glucose metabolism. In the group analysis of the patients, no areas with significantly reduced glucose metabolism could be found.


CONCLUSIONS
No consistent pathological cognitive performance and functional imaging pattern was found. It appears premature to claim specific neuropsychological or neuroimaging findings characteristic of idiopathic environmental intolerance. Therefore cerebral F-18 FDG PET should not be used to corroborate or rule out suspected idiopathic environmental intolerance, a syndrome whose potential biological underpinnings still need to be clarified.
Bornschein
Susanne
S
Department of Psychiatry and Psychotherapy, Technical University (TU) of Munich, Klinikum rechts der Isar, Munich, Germany. s.bornschein@lrz.tu-muenchen.de
Hausteiner
Constanze
C
Drzezga
Alexander
A
Theml
Tina
T
Heldmann
Barbara
B
Grimmer
Timo
T
Perneczky
Robert
R
Jahn
Thomas
T
Schwaiger
Markus
M
Zilker
Thomas
T
Förstl
Hans
H
D000328:Adult; D015415:Biomarkers; D001921:Brain / Q000378:metabolism*; D015331:Cohort Studies; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008297:Male; D008875:Middle Aged; D018777:Multiple Chemical Sensitivity / Q000000981:diagnostic imaging* / Q000523:psychology; D009483:Neuropsychological Tests; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals
D015415:Biomarkers; D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18