Clinical trial NCT02771483: Giant Cell Arteritis and PET Scan (GAPS) Study
Official title: Giant Cell Arteritis and PET Scan (GAPS) Study - Improving the Diagnosis and Prognostication of Giant Cell Arteritis Through the Novel Use of Positron Emission Tomography and Immune Biomarkers
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Giant Cell Arteritis
Lead sponsor: Royal North Shore Hospital
Sponsor class: OTHER
First posted: 2016-05-13
Enrollment: 64
Sex: ALL
Minimum age (years): 50
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: COHORT
Time perspective: PROSPECTIVE
Sampling method: PROBABILITY_SAMPLE
Study population: Suspected GCA

Brief summary: Giant cell arteritis (GCA) is a medium to large vessel vasculitis with a predilection for the superficial cranial and intrathoracic arteries. Diagnosing the condition and predicting which patients will develop large vessel complications remains a challenge. There are limitations with temporal artery biopsy, magnetic resonance angiography and ultrasound of temporal arteries and American College of Rheumatology classification criteria.

Positron emission tomography (PET) has been shown to be a useful modality in detecting inflammation in large intra-thoracic vessels but previously has not been able to accurately detect FDG uptake in the superficial cranial arteries due to poor spatial resolution. Newer scanners can perform finer cuts of the head and can detect uptake in these arteries.

This study has three main components:

1. Cross sectional study assessing the accuracy of PET uptake in the superficial cranial and intrathoracic arteries of suspected GCA patients for the diagnosis of GCA
2. Cohort study assessing the prognostic implication of FDG aortic uptake on aortic diameter at 24 months
3. Cohort study assessing the Th1 and Th17 cytokine profile in patients with and without FDG PET uptake at 0, 6 and 24 months


Eligibility criteria: Inclusion Criteria:

* Rheumatologist, neurologist or ophthalmologist suspect diagnosis of GCA
* Age \> 50
* Meet at least 2 of 1990 American College of Rheumatology classification criteria for GCA

  1. Age \>= 50
  2. ESR \>= 50
  3. New onset localised headache
  4. Temporal artery abnormality (tenderness or decreased pulsation)
  5. Positive biopsy (will not be available at time of enrolment)

Exclusion Criteria:

* Corticosteroid therapy for \> 72 hours before first PET scan
* Prolonged corticosteroid therapy (\> 1 week) for another indication in past 6 months
* History of vasculitis or connective tissue disease
* Active malignancy

Primary outcomes:
measure: Diagnostic accuracy of FDG uptake in the superficial cranial or intrathoracic arteries for the diagnosis of temporal artery biopsy proven GCA amongst patients with suspected GCA
timeFrame: Baseline
Secondary outcomes:
measure: Difference in aortic diameter at 24 months between patients with and without PET scan aortic uptake at time 0.
timeFrame: 24 months
measure: Difference in Th1 and Th17 axis cytokines in patients with and without thoracic large vessel PET uptake at 0, 6 and 24 months
timeFrame: 24 months
measure: Prevalence of varicella zoster virus antigen and DNA in temporal artery biopsy GCA specimens
timeFrame: 24 months
measure: Prevalence of acute varicella zoster IgM serology positivity in biopsy confirmed GCA patients
timeFrame: 24 months
measure: Difference in combined vascular events between GCA patients with and without thoracic large vessel PET uptake at 0, 6 and 24 months
timeFrame: 24 months
measure: Difference in temporal artery histology between GCA patients with and without thoracic large vessel PET uptake at 0 months
timeFrame: Baseline
measure: Difference in temporal artery histology between GCA patients with and without temporal artery PET uptake at 0 months
timeFrame: Baseline
Other outcomes:
Locations:
city: St Leonards
country: Australia
facility: Royal North Shore Hospital
state: New South Wales
Study officials:
affiliation: Royal North Shore Hospital, St Leonards, Australia
name: Anthony M Sammel, MBBS
role: PRINCIPAL_INVESTIGATOR
References:
citation: Sammel AM, Hsiao E, Schembri G, Nguyen K, Brewer J, Schrieber L, Janssen B, Youssef P, Fraser CL, Bailey E, Bailey DL, Roach P, Laurent R. Diagnostic Accuracy of Positron Emission Tomography/Computed Tomography of the Head, Neck, and Chest for Giant Cell Arteritis: A Prospective, Double-Blind, Cross-Sectional Study. Arthritis Rheumatol. 2019 Aug;71(8):1319-1328. doi: 10.1002/art.40864. Epub 2019 Jun 12.