Dr. Conway et al reply.

We thank Sauret et al1 for their interest in our systematic literature review that explored potential diagnostic confusion between giant cell arteritis (GCA) and the coronavirus disease 2019 (COVID-19). This was a particularly important consideration during the early months of the COVID-19 pandemic, when community testing for SARS-CoV-2 was limited and diagnostic tests for GCA were restricted or unavailable due to redeployment of staff.2.

Clinical pathways for patients with giant cell arteritis during the COVID-19 pandemic: an international perspective.

Giant cell arteritis, a common primary systemic vasculitis affecting older people, presents acutely as a medical emergency and requires rapid specialist assessment and treatment to prevent irreversible vision loss. Disruption of the health-care system caused by the COVID-19 pandemic exposed weak points in clinical pathways for diagnosis and treatment of giant cell arteritis, but has also permitted innovative solutions. The essential roles played by all professionals, including general practitioners and surgeons, in treating these patients have become evident. Patients must also be involved in the reshaping of clinical services. As an international group of authors involved in the care of patients with giant cell arteritis, we reflect in this Viewpoint on rapid service adaptations during the first peak of COVID-19, evaluate challenges, and consider implications for the future.

Giant Cell Arteritis and COVID-19: Similarities and Discriminators. A Systematic Literature Review.

OBJECTIVE: To identify shared and distinct features of giant cell arteritis (GCA) and coronavirus disease 2019(COVID-19) to reduce diagnostic errors that could cause delays in correct treatment. METHODS: Two systematic literature reviews determined the frequency of clinical features of GCA and COVID-19 in published reports. Frequencies in each disease were summarized using medians and ranges. RESULTS: Headache was common in GCA but was also observed in COVID-19 (GCA 66%, COVID-19 10%). Jaw claudication or visual loss (43% and 26% in GCA, respectively) generally were not reported in COVID-19. Both diseases featured fatigue (GCA 38%, COVID-19 43%) and elevated inflammatory markers (C-reactive protein [CRP] elevated in 100% of GCA, 66% of COVID-19), but platelet count was elevated in 47% of GCA but only 4% of COVID-19 cases. Cough and fever were commonly reported in COVID-19 and less frequently in GCA (cough, 63% for COVID-19 vs 12% for GCA; fever, 83% for COVID-19 vs 27% for GCA). Gastrointestinal upset was occasionally reported in COVID-19 (8%), rarely in GCA (4%). Lymphopenia was more common in COVID-19 than GCA (53% in COVID-19, 2% in GCA). Alteration of smell and taste have been described in GCA but their frequency is unclear. CONCLUSION: Overlapping features of GCA and COVID-19 include headache, fever, elevated CRP and cough. Jaw claudication, visual loss, platelet count and lymphocyte count may be more discriminatory. Physicians should be aware of the possibility of diagnostic confusion. We have designed a simple checklist to aid evidence-based evaluation of patients with suspected GCA.