PET/CT in Psoriatic Arthritis

When patients with psoriasis develop joint pain, it is often hard to decide whether or not
the pain is due to psoriatic arthritis (PsA). At this time, doctors use information from the
history and physical exam to determine the diagnosis. X-rays, magnetic resonance imaging
(MRI) and ultrasound have been used to help with the diagnosis but all three have
limitations. A newer imaging technique, whole body Positron Emission Tomography/Computed
Tomography (PET/CT) uses the idea that inflammatory cells take up sugar to locate
inflammation in the body. Because patients with PsA have inflammatory cells in their joints
and tendons, this type of scan allows the physician to take a picture of the whole body and
locate inflammation. The investigators have found that some patients with psoriasis (but
without arthritis) have inflammation in joints and tendons even before the patient has
symptoms. In this study, the investigators will explore how well PET/CT works for assessing
inflammation in patients with PsA. This would be a very exciting tool that could be used to
find and treat inflammation before it causes damage or pain.