Giant Cell Arteritis: Practical Pearls and Updates

[Utility of applying a diagnostic algorithm in giant cell arteritis based on the level of clinical suspicion]

INTRODUCTION

To reach the diagnosis of giant cell arteritis (GCA), signs, symptoms, laboratory tests, imaging findings, and occasionally anatomopathological results from temporal artery biopsy are evaluated. This study describes the results of an algorithm analysis based on clinical and ultrasound evaluation of patients with suspected GCA, highlighting its diagnostic utility by contrasting its use in different clinical suspicion scenarios.

METHOD

Prospective multicenter study evaluating patients referred with suspected GCA through a preferential circuit (fast track), grouping them according to low or high clinical suspicion of GCA. Each of these scenarios is evaluated by biopsy and ultrasound for all patients, resulting in positive, indeterminate, or negative outcomes, yielding six possible groups. Potential areas of improvement are explored, emphasizing that, following a negative or indeterminate ultrasound, 18-FDG-PET-CT could be recommended. We analyze the results and application of a diagnostic algorithm, confirming its efficiency and applicability based on whether there is high or low clinical suspicion.

RESULTS

Sixty-nine patients (41 in the high suspicion group and 28 in the low suspicion group). There were 41 new diagnoses of GCA: 35 in the high suspicion group and 6 in the low suspicion group. Using ultrasound alone, the initial algorithm has an overall diagnostic efficiency of 72.5%, which improves to 80.5% when including 18F-FDG-PET/CT. The negative predictive value of ultrasound in patients with low clinical suspicion is 84.6%, and the positive predictive value of ultrasound in patients with high suspicion is 100%, improving sensitivity from 57.1% to 80.8% with 18F-FDG-PET/CT in this scenario. Temporal artery biopsy was performed on all patients, with no differences in sensitivity or specificity compared to ultrasound. In cases where all three tests - ultrasound, biopsy, and 18F-FDG-PET/CT - are performed, sensitivity increases to 92.3% in patients with high clinical suspicion.

CONCLUSION

In situations of high clinical suspicion, the algorithm provides sufficient information for the diagnosis of GCA if ultrasound is positive. A negative ultrasound is sufficient to rule out the diagnosis in the context of low clinical suspicion. 18-FDG-PET-CT may be useful in patients with high suspicion and negative or indeterminate ultrasound results.

Giant Cell Arteritis: A Case-Based Narrative Review of the Literature

Purpose of Review

Giant cell arteritis (GCA) is a chronic, inflammatory condition, primarily affecting the medium and larger arteries. The purpose of this narrative review is to describe GCA in the context of headache and facial pain, based on a case and the available current literature. Understanding the etiology, pathophysiology, the associated conditions, and the differential diagnoses is important in managing GCA.

Recent Findings

In a patient presenting with unilateral facial/head pain with disturbances of vision, GCA should be considered in the differential diagnosis. There is an association of GCA with several comorbid conditions, and infections including coronavirus-19 (COVID-19) infection. Management of GCA primarily depends upon the identification of the affected artery and prompt treatment. Permanent visual loss and other serious complications are associated with GCA.

Summary

GCA is characterized by robust inflammation of large- and medium-sized arteries and marked elevation of systemic mediators of inflammation. An interdisciplinary approach of management involving the pertinent specialties is strongly recommended.

Nummular and Side-locked Headaches for the Otolaryngologist

Side-locked headaches are a common symptom having a wide-ranging differential. Unchanging in laterality, these headaches can represent neuralgias, trigeminal autonomic cephalgias, ophthalmologic disorders, otolaryngologic and craniofacial disorders, vascular disorders, and malignancy. In rarer situations, they have presented secondary to neurosurgical or dermatologic considerations. Loss of cranial nerves and visual changes warrant additional evaluation.

When the Temporal Artery Biopsy is Negative: A Case Series of Headache Attributed to Polymyalgia Rheumatica

INTRODUCTION

Older adults presenting with a new or changed headache pattern in the setting of a diagnosis of polymyalgia rheumatica (PMR) are at risk for incident giant cell arteritis. However, the differential diagnosis of headache has not been evaluated in patients with a negative temporal artery biopsy (TAB). Headache has not been described as a symptom of PMR.

METHODS

After prospectively identifying an individual felt to have headache attributed to PMR, we performed a chart review to identify additional cases. As a secondary outcome, we summarized alternative headache diagnoses in patients with PMR, headache and a negative TAB.

RESULTS

A 75-year-old woman presented with a subacute history of radiating cervical pain in the setting of a 3 month history of lower back stiffness at rest and fatigue. Clinical examination was suggestive of a cervicogenic headache. Following treatment with low-dose corticosteroid for PMR, headaches, cervical mobility and systemic findings resolved with treatment of PMR with low-dose corticosteroid. In our cohort of 36 patients, we identified a single additional patient meeting our study criteria for headache attributed to PMR. Three additional patients met all but 1 diagnostic criterion. The retrospective case was a 73-year-old woman with a subacute history of both morning-predominant headaches and muscle stiffness, diagnosed with PMR. Headaches remitted with low-dose corticosteroid and relapsed with corticosteroid taper.

CONCLUSIONS

Headache attributed to PMR is a steroid-responsive syndrome which should be considered in an older adult presenting with features of PMR, when the TAB is negative. Diagnostic criteria for headache attributed to PMR are proposed.

Giant cell arteritis: is the clinical spectrum of the disease changing?

BACKGROUND

Giant cell arteritis is a vasculitis of large and middle-sized arteries that affects patients aged over 50 years. It can show a typical clinical picture consisting of cranial manifestations but sometimes nonspecific symptoms and large-vessel involvement prevail. Prompt diagnosis and treatment is essential to avoid irreversible damage.

DISCUSSION

There has been an increasing knowledge on the occurrence of the disease without the typical cranial symptoms and its close relationship and overlap with polymyalgia rheumatica, and this may contribute to reduce the number of underdiagnosed patients. Although temporal artery biopsy is still the gold-standard and temporal artery ultrasonography is being widely used, newer imaging techniques (FDG-PET/TAC, MRI, CT) can be of valuable help to identify giant cell arteritis, in particular in those cases with a predominance of extracranial large-vessel manifestations.

CONCLUSIONS

Giant cell arteritis is a more heterogeneous condition than previously thought. Awareness of all the potential clinical manifestations and judicious use of diagnostic tests may be an aid to avoid delayed detection and consequently ominous complications.