Tocilizumab for refractory cerebral arteritis in a patient with systemic lupus erythematosus: A case report.

Cerebral arteritis is a rare (<1%) but life-threatening manifestation of systemic lupus erythematosus (SLE). The optimal treatment of cerebral arteritis in refractory cases remains unclear; conventional immunosuppressive therapy results in improvement in arterial stenosis in only 29% of reported cases. We report a 51-year-old woman with a 20-year history of SLE and rheumatoid arthritis who developed aphasia and right hemiparesis due to haemodynamic cerebral infarction caused by cerebral arteritis. Despite treatment with high-dose glucocorticoids, intravenous cyclophosphamide, mycophenolate mofetil, and anifrolumab, the disease remained progressive with persistently elevated C-reactive protein (CRP) levels and worsening arterial stenosis on magnetic resonance angiography (MRA). Cerebrospinal fluid interleukin-6 (IL-6) level was markedly elevated (1590 pg/mL). After switching from anifrolumab to tocilizumab (TCZ), CRP levels normalised, the patient's neurological condition stabilised, and follow-up MRA suggested improvement in arterial stenosis. TCZ might be a viable treatment option for refractory cerebral arteritis in patients with SLE, particularly in cases of elevated cerebrospinal fluid IL-6 levels. To our knowledge, this is the first reported case suggesting the potential efficacy of TCZ in SLE-related cerebral arteritis.