Teaching NeuroImages: Hippocampal sclerosis in cerebral malaria

Summary

  • 39yo F
  • c/c
    • presented w/
      • fever
      • malasie
      • headache
    • after visiting Tanzania
  • Ex
    • peripheral smear
      • Plasmodium falciparum
      • Plasmodium ovale
    • MRI
      • punctate foci of microhemorrhage throughout
        • deep WM
        • hippocampal diffusion
  • PEx
    • unresponsive
  • Tx
    • quinidine
    • doxycycline
    • primaquine
  • Ex
    • Bil hippocampal sclerosis
  • NeuroEx
    • short-term memory impairment

Further

Terminology

Original

A 39-year-old woman presented with fever, malaise, and headache after visiting Tanzania. Peripheral smear showed Plasmodium falciparum and Plasmodium ovale with parasitemia >14%. Within hours, she became unresponsive. MRI demonstrated punctate foci of microhemorrhage throughout the deep white matter, and hippocampal restricted diffusion (figure). Five days of video-EEG were negative for seizure. She was discharged after 3 weeks of quinidine, doxycycline, and primaquine. Repeat MRI showed bilateral hippocampal sclerosis; repeat EEG was normal. Follow-up examination was only notable for short-term memory impairment.

Figure

Figure

MRI scans in cerebral malaria
Brain MRI with (A) positive diffusion-weighted imaging and (B) apparent diffusion coefficient dropout (arrows) consistent with acute ischemia. (C) Susceptibility-weighted imaging shows small areas of microhemorrhage (arrows) in the deep white matter. (D) Follow-up MRI 2 months later demonstrates bilateral hippocampal sclerosis.

Both microhemorrhages and ischemia are seen in cerebral malaria.1 Diffuse edema and T2 white matter hyperintensities are also common,2 although not appreciated here. Given prolonged EEG monitoring without seizure, the bilateral hippocampal sclerosis is likely secondary to microvascular ischemia.

  1. Potchen M, Kampondeni S, Seydel K, et al. Acute brain MRI findings in 120 Malawian children with cerebral malaria: new insights into an ancient disease. Am J Neuroradiol 2012;33:1740–1746.
  2. Rasalkar DD, Paunipagar BK, Sanghvi D, Sonawane BD, Loniker P. Magnetic resonance imaging in cerebral malaria: a report of four cases. Br J Radiol 2011;84:380–385.