Significant differences in central imaging of histamine-induced itch between atopic dermatitis and healthy subjects
Article first published online: 9 JAN 2012
2008 European Federation of Chapters of the International Association for the Study of Pain
European Journal of Pain
Volume 12, Issue 7, pages 834–841, October 2008
How to Cite
Schneider, G., Ständer, S., Burgmer, M., Driesch, G., Heuft, G. and Weckesser, M. (2008), Significant differences in central imaging of histamine-induced itch between atopic dermatitis and healthy subjects. European Journal of Pain, 12: 834–841. doi: 10.1016/j.ejpain.2007.12.003
- Issue published online: 9 JAN 2012
- Article first published online: 9 JAN 2012
- Received 19 July 2007; Revised 13 November 2007; accepted 5 December 2007
- Positron emission tomography (PET);
- Atopic dermatitis;
Background/aim: This is the first investigation of the central processing of itch in the brain in 8 subjects with atopic dermatitis (AD) in comparison to 6 healthy controls (HC), comparing histamine-induced itch related activations in the frontal, prefrontal, parietal, cingulate cortex, thalamus, basal ganglia and cerebellum.
Methods: We employed 1% histamine-dihydrochlorid-iontophoresis of the left hand, recorded H215O-PET-scans and perception of itch intensity on a numeric rating scale.
Results: There was no significant difference in perceived itch intensity between AD and HC. Significant increase in rCBF was found in HC in the contralateral somatosensory and motor cortex, midcingulate gyrus, and ipsilateral prefrontal cortex; in AD: in the contralateral thalamus, somatosensory, motor and prefrontal cortex and cerebellum, in the ipsilateral precentral, prefrontal, orbitofrontal cortex, insula, pallidum and cerebellum. More brain sites were activated in AD than in HC. Activation in AD was significantly higher in the contralateral thalamus, ipsilateral caudate and pallidum.
Conclusions: We interpret our findings as possible central correlates of changes in the motor system in subjects with chronic itch, with activation of the basal ganglia possibly correlating to the vicious itch-scratch-circle in subjects with chronic itching skin diseases. However, further neuroimaging studies in healthy subjects and also in different skin diseases are needed to understand the complex mechanisms of the processing of itch.