Anti-septin complex positive autoimmune encephalitis after severe falciparum malaria: a case report

Post malaria neurologic syndrome (PMNS) is a rare complication of malaria, usually caused by Plasmodium falciparum. The clinical picture is highly variable and ranges from qualitative disturbances of consciousness and psychosis to damage to the peripheral nerves, usually occurring three to eight weeks after treated malaria.

We report the case of a 54-year-old male who presented with recurrent clinical symptoms three and a half weeks after severe falciparum malaria. After ruling out recurrent malaria, autoimmune encephalitis was suspected. Corticosteroid therapy led to a rapid improvement of the clinical symptoms. The extended examinations (including cranial MRI and FDG-PET/CT) revealed no pathological findings. Routine serologic autoimmune diagnostics remained negative. However, anti-septin complex antibodies were detected in the serum in a cell-based and a tissue-based immunofluorescence assay. Twelve months after discontinuation of corticosteroid therapy, the patient was free of immunosuppressants and completely asymptomatic.

To our knowledge, this is the first case of septin complex autoimmunity with encephalitis associated with PMNS. All physicians treating malaria patients should therefore be aware of this rare condition and consider extended autoimmune diagnostics if routine panels remain unremarkable.