Brain stem encephalitis

Anti-Yo (PCA-1) Cdr2 Cytoplasm of Purkinje cells Cerebellar degeneration, brain stem encephalitis Ovary, breast, gastrointestinal tumors... 

Anti-Hu HuD, HuC, Hel-Nl Nucleus > cytoplasm (all neurons) Encephalomyelitis, SSN, LE, brain stem encephalitis, cerebellar degeneration, myelitis, gastrointestinal pseudoobstruction, extrapyramidal affection SCLC, neuroendocrine tumors... 

Anti-Ri (ANNA-2) NOVA Nucleus > cytoplasm (CNS neurons) Brain stem encephalitis, cerebellar degeneration Breast... 

Anti-Ma2/Ta Ma2 Neurons (subnucleus) LE, brain stem encephalitis, extrapyramidal affection Testis, lung... 

Brain stem encephalitis is characterized clinically by gaze palsy, diplopia, reduced consciousness, and central sleep apnea [54], This disorder is associated with breast cancer and tumors of the female genital organs [55],... 

There is considerable antigen diversity in brain stem encephalitis, with a number of associated antibodies, in particular the Ma, Hu, and Ri antibodies [60]. The Ma2 antibody is associated with brain stem dysfunction, isolated or in combination with diencephalic encephalitis or LE [45]. Vertical gaze palsy is common in these patients [58]. If testicular cancer is not found, lung cancer should be suspected in these patients [61]. One-third of the patients with Ma2 antibodies have narcoleptic-like symptoms, and immune-mediated hypocretin dysfunction has been suggested in such cases [61]. OM with Ri antibodies has traditionally been associated with breast cancer, but the most common tumor in these patients is actually SCLC [62], SCLC is also the predominant tumor in Hu antibody positive patients with brain stem encephalitis. 

The various antibodies are associated with affection of distinct levels of the brain stem. In patients with Ma2 antibodies, the cranial mesencephalon is usually affected, whereas patients with Ri antibodies usually have inflammation in more caudal parts of the mesencephalon, resulting in visual disturbances secondary to involvement of the nuclei of the third, fourth, and sixth cranial nerves (OM). In Hu antibody positive patients, brain stem encephalitis is often combined with medullary symptoms. 

The prognosis of brain stem encephalitis is generally poor, although Ma2 positivity is associated with a better outcome [61]. 

Voltz R, Gultekin SH, Rosenfeld MR, Gerstner E, Eichen J, Posner JB, et al. A serologic marker of paraneoplastic limbic and brain-stem encephalitis in patients with testicular cancer. N Engl J Med 1999 340(23) 1788-1795. 

Barnett M, Prosser J, Sutton I, Halmagyi GM, Davies L, Harper C, et al. Paraneoplastic brain stem encephalitis in a woman with anti-Ma2 antibody. J Neurol Neurosurg Psychiatry 2001 70(2) 222-225. 

Antal EA, Dietrichs E, Loberg EM, Melby KK, Maehlen J. Brain stem encephalitis in listeriosis. Scand Inject Dis. 2005 37(3) 190-194. 

Antal EA, Loberg EM, Dietrichs E, Maehlen J. Neuropathological findings in 9 cases of Listeria monocytogenes brain stem encephalitis. Bruin Pathol. 2005 15(3) 187-191. 

PEM is one of the most frequent cancer-associated syndromes. This complex disorder usually affects several areas of the CNS. Cerebellar and brain stem disorders, as well as limbic encephalitis, are the most common clinical presentations of PEM [31, 32], Focal involvement of the sensorimotor cortex has been described in a few cases [33], and PEM may manifest as epileptic seizures or epilepsia partialis continua [33, 34], or as extrapyramidal symptoms [35], Two-thirds of the patients are affected in both the CNS and the peripheral nervous system. The predominant feature in more than half of these is SN [32, 36], hence the commonly used term is PEM/SN. Autonomic dysfunction is common in PEM/SN patients [36], often presenting as gastrointestinal dysmotility [37]. 

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