Anti-Ma2 related encephalitis

Inflammatory diseases

General description

Anti-Ma2-related encephalitis is an autoimmune encephalitis in which 90% of patients have a paraneoplastic syndrome. Half of the patients have testicular carcinoma. Typical clinical manifestations include limbic encephalitis and brainstem symptoms, often accompanied by daytime sleepiness. In patients with brainstem involvement, oculomotor dysfunctions and vertical gaze paralysis are common. Key diagnostic points include symptoms of autoimmune encephalitis, mesencephalic and hypothalamic symptoms (e.g., daytime sleepiness or cataplexy), and brainstem symptoms (vertical gaze palsy).

Radiographic features

MRI shows abnormal signal in limbic system. One third of patients show abnormal signal and nodular contrast effect in diencephalon (thalamus and hypothalamus) and brainstem.

Non-Space occupying lesion

Limbic encephalitis

Anatomical regions
  • Cerebrum
    Temporal lobe
    Hippocampus
  • Cerebrum
    Temporal lobe
    Amygdala
  • Cerebrum
    Cingulate gyrus
  • Claustrum
  • Cerebrum
    Insula
Symmetric
Bilateral
Morphology
Enlargement / swelling
T2WI
Hyperintensity
FLAIR
Hyperintensity
Symmetric
Bilateral
Nodular
CE T1WI
Enhancement
Non-Space occupying lesion

Diencephalon and brainstem lesion

Anatomical regions
  • Thalamus
  • Hypothalamus
  • Brainstem
Bilateral
T2WI
Hyperintensity
FLAIR
Hyperintensity
Bilateral
Nodular
CE T1WI
Enhancement