Systemic lupus erythematosus in a patient with multiple system atrophy: A case report.

Rationale: Multiple system atrophy is a late-onset rare neurodegenerative movement disorder which results in debilitating disease. Fever frequently ensues in the context of infections which can be associated with significant morbidity and mortality, but among alternative diagnostic possibilities neoplasms and autoimmune disorders should be considered.

Patient Concerns: We describe a case of a prolonged febrile syndrome in a 55-year-old female patient with onset of multiple system atrophy two years before presentation. Patient history and symptoms were not contributive to guide the diagnostic work-up.

Diagnosis: Initial evaluation provided no specific findings. Repeat testing of auto-antibodies revealed positive antinuclear and anti-ds DNA antibodies coupled with low complement which in conjunction with renal biopsy substantiated the diagnosis of systemic lupus erythematosus flare.

Intervention: Pending the biopsy result, treatment with hydroxychloroquine and corticosteroids was initiated. Due to failure to achieve remission, azathioprine was added, but symptoms persisted. Following the diagnosis of lupus nephritis, azathioprine was discontinued and induction treatment with cyclophosphamide in accordance with the Euro-Lupus regimen was initiated and upon completion followed by maintenance therapy with mycophenolate mofetil.

Outcomes: The patient achieved remission after cyclophosphamide was added to treatment with corticosteroids and has not experienced new flares during the next two years. The neurological syndrome has remained stable during this period.

Lessons: To our knowledge, we report the first case of concurrent systemic lupus erythematosus and multiple system atrophy. Prolonged fever presents unique challenges in patients with rare diseases.