Abstract
Purpose :
Ultrasound is regarded as a useful test in diagnosing Giant Cell Arteritis (GCA). Recent studies have shown ultrasound to be more sensitive than Temporal artery Biopsy(TAB), in patients suspected to have GCA.
We aim to analyse the sensitivity and specificity of TAB in diagnosing GCA in patients who were negative on temporal artery ultrasound and to look at effectiveness of temporal artery ultrasound in relation to time after steroid treatment.
Methods :
Our current practise is to perform ultrasound on all patients suspected to have GCA and perform TAB on those who are negative on ultrasound.
We analysed the data of Sixty-five patients who underwent TAB between May 2014 – November 2017. The sensitivity and specificity of ultrasound and TAB were analysed.
Results :
Average histology size of TAB before November 2016 was 16.1mm (range 3-36mm). Since November 2016, following BSR and BHPR recommendations, this increased to 20.2mm (range 10-27mm) histology size and 22.4mm (range 17-30mm) documented cut specimen size.
The sensitivity of TAB in patients who were negative on ultrasounds (n=55) was 30% (CI 12-54%) and specificity was 97% (CI 85-100%).
Ultrasounds performed <1 day of commencing steroids had a sensitivity of 46.5% and specificity of 100%. This reduces to 14.3% sensitivity and 85.7% specificity when treated for >1 day.
Conclusions :
Ultrasound of temporal artery remains a useful diagnostic tool for GCA if performed within 1 day of commencing steroids, as reliability reduces with increased time on treatment. It is more cost effective and quicker to perform than TAB when done by appropriately trained staff.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.