Can autoimmune encephalitis occur in males?

Can Autoimmune Encephalitis Occur in Males?

Yes, autoimmune encephalitis absolutely occurs in males, though it is more common in females with a male-to-female ratio of approximately 1:2. 1

Epidemiology and Sex Distribution

• Autoimmune encephalitis affects both males and females across all age groups, from children to the elderly 2, 3
• The median age at presentation is 25 years, with males representing approximately one-third of cases 1
• NMDA receptor encephalitis, the most common subtype in patients under 30 years, shows this 1:2 male-to-female predominance 4, 1

Clinical Manifestations in Males

Males present with the same core clinical features as females, including:

• Polysyndromic presentation with behavioral/psychiatric symptoms, cognitive changes, seizures, movement disorders, and autonomic dysfunction 2
• Rapid progression with symptoms typically developing within six weeks 5
• Neurological symptoms that may be more prominent than psychiatric manifestations, particularly in children 3

Tumor Associations in Males

A critical distinction is that males with autoimmune encephalitis should undergo testicular ultrasound screening for teratoma, as testicular teratomas can trigger NMDAR encephalitis in males just as ovarian teratomas do in females 1

• While 20-50% of females with NMDAR encephalitis have ovarian teratomas, males can harbor testicular teratomas that require surgical removal 1
• All males with suspected autoimmune encephalitis should receive CT chest/abdomen/pelvis with contrast as initial cancer screening 4, 1

Documented Male Cases

The medical literature contains multiple documented cases of autoimmune encephalitis in males:

• A 53-year-old male with HIV developed fatal encephalitis following yellow fever vaccination 2
• A 56-year-old male developed longitudinal myelitis with confirmed autoimmune etiology 2
• A 23-year-old male presented with meningoencephalitis later diagnosed as ADEM (acute disseminated encephalomyelitis) 2

Treatment Approach

Treatment for males is identical to females and should be initiated immediately once infection is excluded, without waiting for antibody confirmation 4:

• First-line therapy: pulse-dose methylprednisolone (1g IV daily for 3-5 days) plus either IVIG or plasma exchange 4
• Second-line therapy: rituximab (preferred) or cyclophosphamide if no improvement within 2-4 weeks 4
• Tumor removal if identified, as this is critical for treatment success 4, 1