Malignant Catatonia as the Presenting Manifestation of Systemic Lupus Erythematosus.

Malignant catatonia represents a potentially life-threatening presentation of catatonia that typically includes fever, autonomic instability, and cardiovascular collapse. Failure to respond to benzodiazepines, particularly with an increase in catatonic signs, should raise suspicion for the presence of malignant catatonia. Here, we report the first case of malignant catatonia as the initial manifestation of systemic lupus erythematosus (SLE) presenting in a 15-year-old girl who developed progressive catatonia that was resistant to immunosuppressive therapy with pulse corticosteroids, intravenous immunoglobulin (IVIg), and cyclophosphamide and required electroconvulsive therapy for clinical improvement. Catatonia in SLE is reviewed and contrasted with other types of autoimmune encephalopathies, anti-NMDAR antibody encephalitis, and Hashimoto encephalopathy (HE), highlighting the diagnostic considerations and clinical challenges.