The Diagnostic Dilemma of "The Great Imitator": Heart and Cerebral Involvement of Lupus Manifesting as Bilateral Upper and Lower Extremity Weakness.

Background: Systemic lupus erythematous (SLE) is an autoimmune condition which can cause complex, multiorgan dysfunction. This autoimmune disease is caused by the production of antinuclear antibodies which allows this disease to target virtually any organ in the human body. When a patient experiences an unpredictable worsening of disease activity, it is generally considered a lupus flare. Organ dysfunction due to a lupus flare tends to manifest as separate events in the literature and rarely do we witness multiple compounding organ failures during a lupus flare. If we do witness organ dysfunction and failure, rarely do we see cardiac and cerebral involvement. Typically, patients take immunosuppressants for a long term to avoid the patient's disease process from worsening and to provide prophylaxis from a flare to occur. Despite the availability in preventive strategies, some patients will have increased disease activity multiple times throughout their lifetime and will need increases in their medication doses or changes to their regimen. Some flares can be managed in the clinic, but more severe ones may be life-threatening that they require intravenous medications and hospitalization to achieve remission. In the following case, we see a patient with a past medical history of SLE on multiple immunosuppressants who arrived at the hospital with acute, bilateral weakness of the upper and lower extremities. It was later determined via various imaging and laboratory testing that she was having an SLE flare that was directly causing myocarditis which progressed to global ischemia of the brain via myocardial hypoperfusion. She experienced substantial recovery from her flare with treatment with high-dose, intravenous corticosteroids. Conclusion: Our patient presented with reversible focal neurological deficits, elevated high-sensitive troponin levels, and high lupus serum antibodies who showed significant improvement after the introduction of high-dose steroids. This case recommends keeping a large differential and to not discount patients' past comorbidities for causing atypical symptomatology.