Brachial Plexitis as a Rare Manifestation of Giant Cell Arteritis: A Case-Based Review.

Background: Giant cell arteritis (GCA) is the most common systemic vasculitis, typically involving large and medium-sized arteries. It usually presents with cranial ischemic symptoms, although peripheral nervous system involvement may also occur. Brachial radiculoplexopathy is a particularly rare manifestation. Early recognition is essential, as prompt corticosteroid therapy generally results in substantial neurological improvement. Case report: A 69-year-old man with a history of arterial hypertension, diabetes mellitus, dyslipidaemia, hypothyroidism, and polymyalgia rheumatica presented with headache, cervical pain, and left upper limb weakness. Electrophysiological studies showed acute neurogenic changes involving the C5-C6 distribution. Temporal artery ultrasound showed a halo sign, and biopsy confirmed the diagnosis of GCA. The patient achieved full neurological recovery after four weeks of treatment with corticosteroids and tocilizumab. Literature review: A narrative review was conducted using PubMed/MEDLINE, Scopus, Embase, and Web of Science databases. Twenty-nine reported cases of brachial radiculoplexopathy associated with GCA, were identified. The mean age was 68 years, with a balanced sex distribution. Neurological in-volvement was bilateral in 59% of cases and mainly affected the C5-C6 roots. All patients had elevated in-flammatory markers, and temporal artery biopsy confirmed GCA in 97% of cases. Most patients respond-ed rapidly to corticosteroid therapy, while only a few required additional immunosuppressive treatment. Conclusions: Brachial radiculoplexopathy is a rare neurological manifestation of GCA that may occur at disease onset and pose a diagnostic challenge. Awareness is essential for timely diagnosis and treatment, as most patients respond favourably to corticosteroids. Tocilizumab may represent an effective steroid-sparing option in selected cases.