Teaching Video NeuroImages: Opsoclonus in anti-DPPX encephalitis

Summary

Terminology

Original

  • 49yo M
  • c/c
    • 15m Hx of
      • binocular diplopia
      • oscillopsia
    • 6mo Hx of
      • headache
      • memory loss
      • anorexia
      • myalgias
      • 105-pound weight loss w/o diarrhea
  • PEx
    • neuro-opthalmic assessment
      • episodic burst of opsoclonus
      • intermittent jerk nystagmus
      • saccadic pursuit
      • slowed & dysmetric saccades
      • fixation(–)
  • Ex
    • anti-DPPX Ab (–) CSF
  • Dx
    • anti-DPPX encephalitis
  • Rx
    • IV merhylprednisolone
    • plasmapheresis
    • rituximab
  • Prognosis

A 49-year-old man presented with a 15-month history of binocular diplopia and oscillopsia and a 6-month history of headaches, memory loss, anorexia, myalgias, and unintentional 105-pound weight loss without diarrhea. Neuro-ophthalmic assessment revealed episodic bursts of opsoclonus, intermittent jerk nystagmus, saccadic pursuit, and slowed and dysmetric saccades, and he was unable to maintain fixation (video 1). Anti-DPPX antibodies were positive in the CSF. He was treated with IV methylprednisolone, plasmapheresis, and rituximab, and his ocular symptoms resolved several months after treatment. Opsoclonus is an ocular manifestation of anti-DPPX encephalitis, which may also cause nystagmus, skew deviation, and saccadic pursuit due to DPPX expression in the cerebellum.1,2

Video 1

Voluntary eye movements were slow and limited in all directions of gaze. The patient had saccadic pursuit, dysmetric saccades, and was unable to maintain fixation. He had episodic bursts of opsoclonus with jerk nystagmus. Six months after treatment, his eye movements were normal apart from a small amplitude gaze-evoked nystagmus.

Video

References

  1. Tobin WO, Lennon VA, Komorowski L, et al. DPPX potassium channel antibody: frequency, clinical accompaniments, and outcomes in 20 patients. Neurology 2014;83:1797–1803.
  2. Balint B, Jarius S, Nagel S, et al. Progressive encephalomyelitis with rigidity and myoclonus: a new variant with DPPX antibodies. Neurology 2014;82:1521–1528.