A Rare Case of Giant Cell Arteritis Affecting Two Giants: Pulmonary and Root of Aorta Aneurysm

ABSTRACT

Aneurysms of pulmonary arteries and aorta are rare, typically caused by infections, congenital heart defects, vascular abnormalities, or medical interventions. This report presents an unusual case of a 72‐year‐old man with a history of smoking, hypertension, and emphysema, who was found to have a large pulmonary artery aneurysm (63.5 mm) and aortic root dilation (46 mm). Despite normal inflammatory markers and no typical giant cell arteritis (GCA) symptoms, histopathology following surgical repair revealed focal GCA as the underlying cause. The patient underwent successful valve‐sparing root replacement and was subsequently treated with prednisone and tocilizumab, showing clinical improvement. This case underscores the existence of a rare GCA phenotype—extracranial GCA—that affects major arteries without cranial involvement and often lacks classic symptoms. Extracranial GCA carries serious risks, including dissection and rupture, particularly in hypertensive individuals. The continuous inflammation in GCA leads to medial degeneration and aneurysm formation. Advancements in imaging have improved early detection and intervention, though the rarity of this condition limits large‐scale studies. As a result, diagnosis and treatment rely heavily on case reports. Glucocorticoids and immunomodulators remain the mainstay of therapy, but more research is needed to optimize management for this atypical GCA presentation.

Summary.

• We highlight the occurrence of concurrent pulmonary artery and aortic root aneurysms caused by giant cell arteritis.

• The rare extracranial phenotype of GCA can progress silently.

• Clinicians need to consider GCA in elderly patients with unexplained large‐vessel aneurysms, even without typical symptoms or raised inflammatory markers.

1. Introduction

Giant cell arteritis (GCA) is the most common vasculitis in patients > 50 years. It is a granulomatous vasculitis that affects large vessels (i.e., arteries outside the organs), particularly the aorta and its extracranial branches (carotid, subclavian, axillary, vertebral, maxillary, occipital, and temporal arteries) [1]. The traditional concept of GCA has focused on cranial symptoms such as headache and visual disturbance, but extracranial manifestations such as constitutional symptoms, polymyalgia, and limb claudication have also long been recognized. These symptoms may coincide with cranial GCA, occur as an independent clinical subset (large‐vessel [LV] GCA), or overlap with Polymyalgia rheumatica (PMR) [2]. GCA and PMR are closely related systemic inflammatory disorders, with 40%–60% of patients with GCA exhibiting features of PMR, and approximately 10%–20% of patients with PMR subsequently developing GCA.

The real diagnostic challenge arises when patients have none of the typical cranial symptoms and no signs of PMR. In these situations, GCA may progress quietly, often going unnoticed until complications such as aneurysm or vascular dissection develop. Inflammatory markers like Erythrocyte sedimentation rate (ESR) and C‐reactive protein (CRP) may be normal, which can further delay suspicion. Without the classic warning signs, the disease can easily be mistaken for infection, malignancy, or other inflammatory disorders. Imaging can help, but in some cases, the diagnosis isn't confirmed until after surgical intervention and tissue biopsy. The case we present illustrates exactly this scenario—a rare and silent form of GCA involving both the pulmonary artery and the aortic root, diagnosed only after surgical treatment for large‐vessel aneurysms.

2. Case Report

2.1. Clinical History and Examination

The patient is a 72‐year‐old male with a medical history notable for severe chronic obstructive pulmonary disease (COPD) [FEV1 44% of predicted], hypertension, hyperlipidemia, and a history of smoking. He presented to his primary care physician with complaints of progressively worsening breathlessness on exertion, easy fatigability, a non‐productive cough, and unintentional weight loss of approximately 20 pounds over the past 2 months.

Despite a 5‐day course of prednisone (40 mg daily) and an increase in his inhaler therapy, his symptoms did not improve. A non‐contrast chest Computed Tomography (CT) scan was ordered, which revealed a pulmonary artery aneurysm with dilation of the pulmonary artery measuring 63.5 mm in diameter (Figure 1).

FIGURE 1.

Chest CT shows a markedly dilated pulmonary artery, measuring 63.5 mm in diameter, indicative of aneurysmal changes.

2.2. Investigations and Treatment

The patient was subsequently referred to a pulmonary clinic, where further tests were conducted, including a 2D transthoracic echocardiogram (TTE) and pulmonary function tests. The results of the pulmonary function tests were unchanged compared to prior measurements. The transthoracic echocardiogram (TTE) showed a dilated ascending aorta measuring 42 mm with dilated sinuses of Valsalva measuring 46 mm. Left ventricular systolic function was normal at 60%–65%, with normal chamber sizes of both the left and right ventricles. Mild to moderate aortic, tricuspid, and pulmonary regurgitation were also noted. A chest CT angiogram confirmed an aortic root aneurysm (measuring 46 mm), an ascending aorta (measuring 42 mm) (Figure 2).

FIGURE 2.

CT chest angiogram showing ectasia of the sinus of Valsalva, with cusp‐to‐cusp measurement of 46 mm.

The case was discussed with the cardiology and cardiothoracic surgery teams. Following this, the patient underwent both right and left heart catheterizations. The right heart catheterization findings included a cardiac output of 4.9 L/min, a mean pulmonary capillary wedge pressure of 6–8 mmHg, a mean pulmonary artery pressure of 17 mmHg, and a mean right atrial pressure of 2–3 mmHg, which suggested no evidence of resting pulmonary hypertension. The left heart catheterization was largely unremarkable except for mild, nonobstructive coronary disease.

Because of the markedly enlarged pulmonary artery, surgical intervention was recommended in line with American Heart Association (AHA) guidelines, which advise repair of pulmonary artery aneurysms larger than 5.5 cm to prevent rupture, progressive right‐sided heart failure, or major pulmonary embolism. In comparison, the ascending aorta measured 4.2 cm and was associated only with mild to moderate aortic insufficiency, so it did not meet criteria for surgical repair. After a detailed discussion of the medical and surgical options, including potential risks and benefits, the patient chose operative management. The procedure included aortic valve repair with valve‐sparing root replacement using the Yacoub technique and Gore‐Tex ring annuloplasty, valve‐sparing pulmonary root replacement, replacement of the main pulmonary artery with a 13 mm Dacron graft, and tricuspid valve ring annuloplasty.

3. Conclusion and Result

The postoperative course was uncomplicated, and the patient was enrolled in cardiac rehabilitation. Interestingly, an aneurysmal tissue biopsy obtained from both aortic and pulmonary vessel walls revealed medial degenerative changes consistent with giant cell arteritis. He was referred to a rheumatologist, who started him on the Giant Cell Arteritis Actemra (GiACTA) protocol, a combination of tocilizumab and a glucocorticoid taper.

4. Discussion

GCA most often draws attention through its cranial features, headache, vision loss, and scalp tenderness—which prompt urgent evaluation. However, a growing body of literature now recognizes a subset of patients with ‘large‐vessel’ GCA, where inflammation targets the aorta and its major branches without any cranial symptoms [3]. Our patient's case underscores how easily this form can be missed, especially when it presents silently with aneurysmal changes and normal inflammatory markers.

Differential diagnoses for GCA include other forms of vasculitis such as Takayasu arteritis, polyarteritis nodosa, and small vessel vasculitis, as well as non‐vasculitis inflammatory conditions like sarcoidosis, syphilitic arteritis, and tuberculous arteritis. However, in our case, these were excluded based on clinical presentation, evidence of large vessel involvement, and biopsy findings showing medial degenerative changes consistent with GCA, which confirmed the diagnosis.

Pulmonary artery involvement in GCA is exceedingly rare. While the aorta is a known target, isolated or combined pulmonary artery aneurysms have been reported in only a handful of cases [4, 5, 6]. In this patient, the involvement of both the pulmonary artery and the aortic root was highly unusual, something rarely seen in clinical practice, and only one such case has been described in the literature so far. What made the case even more challenging was the complete absence of typical systemic signs like fever, symptoms of PMR, or elevated inflammatory markers such as ESR and CRP. Instead, the patient presented with nonspecific symptoms such as fatigue, weight loss, and features of fever of unknown origin (FUO), which further obscured the diagnosis. As a result, GCA was not initially considered among the differential diagnoses. It wasn't until after surgery, when tissue samples were examined under the microscope, that the true cause—focal GCA—was finally revealed.

Surgery was recommended because the aneurysms were large and at significant risk of rupturing. The team chose a valve‐sparing root replacement using the Yacoub technique, along with grafting of the pulmonary artery, which helped preserve the heart's natural structures and led to a smooth recovery. Examination of the tissue confirmed medial degeneration and granulomatous inflammation, consistent with GCA. After surgery, the patient was started on tocilizumab and prednisone following the GiACTA protocol [7], a treatment approach known to effectively control disease activity while reducing the need for long‐term steroids.

This case underscores the often subtle and challenging nature of extracranial GCA, particularly when it involves less common vascular territories. In elderly patients presenting with unexplained aneurysmal disease, maintaining a high index of suspicion is crucial. While advanced imaging techniques such as Positron emission tomography (PET‐CT) and Magnetic resonance angiography (MRA) can provide valuable clues suggestive of vasculitis before any surgical intervention, histological confirmation through biopsy remains the definitive method for diagnosis. Given the rarity of such atypical presentations, standardized screening protocols are lacking, and much of our understanding continues to come from case reports like this one [8]. This highlights the importance of careful clinical evaluation and the need to consider GCA even in less typical scenarios to ensure timely diagnosis and management.

5. Summary

The simultaneous development of pulmonary artery and aortic root aneurysms secondary to GCA is an exceptionally rare occurrence. GCA may lack typical symptoms like temporal headaches, visual disturbances, or high inflammatory markers. In elderly patients exhibiting nonspecific symptoms—such as exertional dyspnea, fatigue, unintentional weight loss, or prolonged low‐grade fever—GCA should be considered in the differential diagnosis. With advancements in imaging techniques and increasing consensus on vascular surveillance, such diagnoses are becoming less incidental. A multidisciplinary approach, along with protocol‐based treatment strategies like the GiACTA regimen, has led to improved detection and successful clinical outcomes.

Author Contributions

Gajendra Acharya: conceptualization, supervision, writing – original draft, writing – review and editing. Hafiza Baloch: conceptualization, supervision, writing – review and editing. Pradeep Masuta: supervision, writing – review and editing. Robert Kimelheim: supervision, writing – review and editing. Rohit Pandit: writing – original draft, writing – review and editing. Prabal Tiwari: writing – review and editing.

Ethics Statement

Ethical approval was not required for the case report per the country's guidelines.

Consent

Written informed consent was obtained from the patient, publication, and any accompanying images. A copy of the consent is available for review by the Editor‐in‐chief on request.

Conflicts of Interest

The authors declare no conflicts of interest.

Acharya G., Baloch H., Masuta P., Pandit R., Kimelheim R., and Tiwari P., “A Rare Case of Giant Cell Arteritis Affecting Two Giants: Pulmonary and Root of Aorta Aneurysm,” Clinical Case Reports 13, no. 12 (2025): e71311, 10.1002/ccr3.71311.

Data Availability Statement

The data supporting this article's findings are available from the corresponding author upon reasonable request.