Broadening the clinical spectrum of giant cell arteritis: from the classic cranial to the predominantly extracranial pattern of the disease

ABSTRACT

Introduction

Giant cell arteritis (GCA) is a large vessel (LV) vasculitis that affects people aged 50 years and older. Classically, GCA was considered a disease that involved branches of the carotid artery. However, the advent of new imaging techniques has allowed us to reconsider the clinical spectrum of this vasculitis.

Areascovered

This review describes clinical differences between patients with the cranial GCA and those with a predominantly extracranial LV-GCA disease pattern. It highlights differences in the frequency of positive temporal artery biopsy depending on the predominant disease pattern and emphasizes the relevance of imaging techniques to identify patients with LV-GCA without cranial ischemic manifestations. The review shows that so far there are no well-established differences in genetic predisposition to GCA regardless of the predominant phenotype.

Expert commentary

The large branches of the extracranial arteries are frequently affected in GCA. Imaging techniques are useful to identify the presence of ’silent’ GCA in people presenting with polymyalgia rheumatica or with nonspecific manifestations. Whether these two different clinical presentations of GCA constitute a continuum in the clinical spectrum of the disease or whether they may be related but are definitely different conditions needs to be further investigated.

KEYWORDS:

• Giant cell arteritis
• large vessel vasculitis
• polymyalgia rheumatica
• clinical features
• temporal artery biopsy
• imaging techniques
• ultrasound
• positron emission computed tomography (PET-CT) with 18F-fluorodeoxyglucose (FDG)

Article highlights

• Patients with the cranial giant cell arteritis (GCA) pattern often have different clinical manifestations compared to those with a predominantly extracranial large vessel (LV) vasculitis pattern of disease.

• The diagnostic yield of temporal artery biopsy differs in patients with cranial GCA compared to those with a predominantly extracranial LV-GCA pattern.

• Imaging techniques help us identify patients with LV-GCA without cranial ischemic manifestations of the disease.

• ‘Occult’ LV-GCA can be seen in some patients presenting as isolated polymyalgia rheumatica.

• There are no apparent differences in genetic predisposition to GCA regardless of the predominant cranial or extracranial phenotype.

• It is necessary to look for markers that help us explain the clinical differences between GCA patients with a predominantly cranial and extracranial phenotype.

Declaration of Interest

M González-Gay research is supported by the Spanish Ministry of Health, Instituto de Salud Carlos III (ISCIII), Spanish Red de Investigación RICORS (RD21/0002/0025). The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Additional information

Funding

This paper was not funded.