Maladie de Horton et plexite brachiale C5–C6 : une observation avec revue de la littérature

Abstract

Shoulder palsy due to brachial plexopathy (or lower cervical radiculopathy) is a rare occurrence in patients with giant cell temporal arteritis (TA). We report a patient with C5 plexopathy revealing TA, with review of the literature. A 67-year-old woman presented with a complex neurological syndrome of rapid onset, including a left trigeminal neuralgia, painless masticatory palsy, impaired swallowing, and severe palsy of the left shoulder, corresponding to a C5 plexitis. Giant cell arteritis was suspected on clinical and laboratory grounds and was documented on temporal artery biopsy. Treatment with pulse methylprednisolone (100 mg every 8 hours for three days), followed by prednisone (1 mg/kg daily), resulted in progressive improvement of the neurological deficits, full shoulder strength being recovered within 6 months. An extensive world literature allowed us to review 23 other cases of TA complicated by either lower cervical radiculopathy or C5 brachial plexopathy. These peripheral neuropathic manifestations occurred sometimes bilaterally and were isolated or, less often, part of a mononeuritis multiplex. Involved patients were relatively young (mean age 67 years) and 54% were men. The pathophysiology of TA-associated C5 radiculopathy or brachial plexitis is still poorly understood. Fortunately, functional prognosis was consistently good with corticosteroid treatment. Giant cell arteritis should always be considered in elderly or middle-aged patients presenting with C5 radiculopathy or plexopathy and elevated inflammatory markers.