Clinical Trial Details
— Status: Terminated
Administrative data
NCT number |
NCT02828787 |
Other study ID # |
RB 15.212 PRURIM |
Secondary ID |
|
Status |
Terminated |
Phase |
N/A
|
First received |
|
Last updated |
|
Start date |
January 16, 2017 |
Est. completion date |
May 31, 2018 |
Study information
Verified date |
November 2020 |
Source |
University Hospital, Brest |
Contact |
n/a |
Is FDA regulated |
No |
Health authority |
|
Study type |
Interventional
|
Clinical Trial Summary
The main objective of this study is to identify by functional and structural MRI which are
the brain areas activated in various pruritic situations to deduct a model describing the
different causes of pruritus.
The investigators are going to compare two chronic pruritus conditions (histaminergic
urticaria and non histaminergic: psoriasis) to a healthy control group.
The secondary objective of this study is to specify a classification index from the
physiological results obtained by brain imaging to differentiate multiple types of pruritus.
Description:
Particularly invalidating in some cases, pruritus is defined as an unpleasant sensation that
causes the need to scratch.
Epidemiologically, it is a common disorder as a third of the population feels in a given
week. Treatment is difficult, especially as the pathophysiological mechanisms remain poorly
understood, particularly in the central nervous system.
Specific pathways, or at least selective of the pruritus of transmission have been
identified. From the skin to the brain, two ways exist: a histaminergic pathway (classical),
and a non-histaminergic pathway (related to the activation of PAR-2 receptors by serine
proteases). If urticaria belongs to the first track, the respective share of each channel is
unknown to other causes of pruritus. The pruriceptors, located in the skin, transmit
information by specific fibers at the spinal cord, which then project through the lateral
spinothalamic tract to the thalamus. Then at midbrain and cortex, a vast network involving
sensorial areas, motor and emotional areas was identified by functional neuroimaging, with
activation zones which may be different depending on two channels (with overlapping zones ).
The contribution to the perception of pruritus of these brain regions is the focus of current
research.
A promising non-invasive method to study the pruritus channels with neuroimaging is to use
the phenomenon of "contagious pruritus': seeing other people scratching, itching and
sometimes scratching is induced in the observer, and the activated brain network is similar
to that which is activated by pruritus usually. This phenomenon is even more important in
subjects with atopic dermatitis than in healthy subjects.
In this project, the investigators plan to characterize pruritus central pathways in patients
with different types of chronic pruritus compared to healthy subjects, particularly regarding
the respective contributions of histaminergic pathways (pathway involved in pruritus of
hives) and "PAR-2-ergic" (pathway involved in the itch of psoriasis).