Purpose Neurological manifestations during systemic lupus (SLE) are common, and can jeopardize the functional or vital prognosis of patients .

Limbic encephalitis (LE) is a rare and serious neurological syndrome that selectively affects structures of the limbic system. The main clinical manifestations are seizures associated with episodic memory and behavioral disorders. They are essentially of viral or paraneoplastic origin. Dysimmunitary etiologies, in particular systemic lupus erythematosus, are rarely described and have recently been demonstrated (4–6). However, there remains a lack of understanding about the frequency and strength of this association.

Methods We report a clinical case of a patient with limbic encephalitis complicating SLE.

Results A 36-year-old woman was admitted to our service because of fever, headache, encephalopathy followed by severe, generalized seizures, memory disorders and altered state of consciousness. The patient had a history of SLE for 9 years, under hydroxychloroquine. At the admission, general examination revealed memory disorders. The antiphospholipid antibodies were negative. T2-weighted, fluid-attenuated inversion recovery magnetic resonance imaging showed hyper signals in the hippocampus and amygdala. At the lumbar puncture, the cerebrospinal fluid was normal. Anti-neuronal antibodies were negative. Whole-body computed tomography and positron emission tomography (PET-CT) excluded malignancy. The diagnosis of limbic encephalitis secondary to SLE was retained. Acyclovir was given under the presumptive diagnosis of human herpes virus encephalitis, but neither HHV-6 virus DNA nor anti-N-methyl-D-aspartate receptor antibody was detected in the Cerebrospinal fluid. High-dose corticosteroid therapy was initiated associated with polyvalent immunoglobulin. Monthly cures (X6) of cyclophosphamide were associated followed by mycophenolate mofetil. The patient also received antiepileptic therapy, hydroxychloroquine was maintained. Brain MRI at 3 months of treatment revealed hippocampal atrophy. The evolution at 8 months showed a slight improvement in memory disorders

Conclusions ALE is a rare complication of SLE. Therapeutic management is not codified, but the use of immunoglobulins, high-dose corticosteroid therapy and immunosuppressants are recommended. Rituximab is also used in refractory cases. The prognosis depends on the early diagnosis of specific therapeutic management.