Systematic Review of the Yield of Temporal Artery Biopsy for Suspected Giant Cell Arteritis.

Purpose: To determine the positive yield (utility rate) of temporal artery biopsy (TAB) in patients with suspected giant cell arteritis (GCA).
Study Design: Systematic review (CRD42017078508) and meta-regression.
Materials and Methods: All articles concerning TAB for suspected GCA with English language abstracts from 1998 to 2017 were retrieved. Articles were excluded if they exclusively reported positive TAB, or only cases of known GCA. Where available, the pre-specified predictors of age, sex, vision symptoms, jaw claudication, duration of steroid treatment prior to TAB, specimen length, bilateral TAB, and use of ultrasound/MRI (imaging) were recorded for meta-regression.
Results: One hundred and thirteen articles met eligibility criteria. The I ² was 92%, and with such high heterogeneity, meta-analysis is unsuitable. The median yield of TAB was 0.25 (95% confidence interval 0.21 to 0.27), with interquartile range 0.17 to 0.34. On univariate meta-regression age (coefficient 0.012, p  = 0.025) was the only statistically significant patient factor associated with TAB yield.
Conclusions: Systematic review revealed high heterogeneity in the yield of TAB. The median utility rate of 25% and its interquartile range provides a benchmark for decisions regarding the under/overutilization of TAB and aids in the evaluation of non-invasive alternatives for the investigation of GCA.