Pseudomonas meningoencephalitis masquerading as a stroke in a patient on tocilizumab.

A previously high-functioning woman presents with clinical and CT features of a subacute ischaemic stroke. Her medical history is relevant for refractory giant cell arteritis on long-term high-dose prednisolone and recent commencement of tocilizumab (interleukin-6 monoclonal antibody). The potential for stroke mimic is considered and a magnetic resonance brain scan is requested. She rapidly deteriorates within 24 hours of admission and unexpectantly dies. An autopsy reveals that she has bilateral pulmonary emboli with lower limb deep vein thrombosis and Pseudomonas meningoencephalitis with frank pus on the brain. We discuss the potential risks of immunosuppression and the role of imaging in the diagnosis of stroke.