Ventral striatal and septal area hypermetabolism on FDG-PET in herpes simplex viral encephalitis

  • T. SinghalEmail author
  • I. Solomon
  • F. Akbik
  • S. Smirnakis
  • H. Vaitkevicius
Case Report


A 71-year-old man presented with sudden onset, generalized tonic-clonic seizures and altered mental status. Initial brain magnetic resonance imaging was normal but a brain FDG-PET scan showed hypermetabolism in the left ventral striatum and septal area. Initial cerebrospinal fluid (CSF) examination showed mildly elevated protein but herpes simplex virus (HSV) polymerase chain reaction (PCR) was negative. A repeat CSF examination performed 9 days later showed a positive HSV PCR. Histopathological and immunohistochemical examination of autopsy specimen confirmed the presence of CD45+ lymphocytes and HSV antigen, suggesting the presence of both inflammation and viral infection corresponding to PET abnormality.


Herpes simplex virus Encephalitis PET Fluorodeoxyglucose 



We gratefully acknowledge Prof. Martin A Samuels, MD, and Prof. David Silbersweig, MD, for their intellectual inputs and encouragement.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.


  1. Abrantes JL, Alves CM, Costa J et al (2012) Herpes simplex type 1 activates glycolysis through engagement of the enzyme 6-phosphofructo-1-kinase (PFK-1). Biochim Biophys Acta 1822(8):1198–1206CrossRefGoogle Scholar
  2. Jennische E, Eriksson CE, Lange S, Trybala E, Bergstrom T (2015) The anterior commissure is a pathway for contralateral spread of herpes simplex virus type 1 after olfactory tract infection. J Neurovirol 21(2):129–147CrossRefGoogle Scholar
  3. Kiernan JA (2009) Barr’s the human nervous system. Lippincott Williams & Wilkins, BatimoreGoogle Scholar
  4. Mark LP, Daniels DL, Naidich TP, Hendrix LE, Maas E (1994) Anatomic moment. The septal area. AJNR Am J Neuroradiol 15(2):273–276Google Scholar
  5. McCarthy KM, Tank DW, Enquist LW (2009) Pseudorabies virus infection alters neuronal activity and connectivity in vitro. PLoS Pathog 5(10):e1000640CrossRefGoogle Scholar
  6. Menendez CM, Carr DJJ (2017) Herpes simplex virus-1 infects the olfactory bulb shortly following ocular infection and exhibits a long-term inflammatory profile in the form of effector and HSV-1-specific T cells. J Neuroinflammation 14(1):124CrossRefGoogle Scholar
  7. Saito Y, Price RW (1984) Enhanced regional uptake of 2-deoxy-D-[14C]glucose in focal herpes simplex type 1 encephalitis: autoradiographic study in the rat. Neurology 34(3):276–284Google Scholar
  8. Sanchez EL, Lagunoff M (2015) Viral activation of cellular metabolism. Virology 479-480:609–618Google Scholar
  9. Sellner J, Trinka E (2012) Seizures and epilepsy in herpes simplex virus encephalitis: current concepts and future directions of pathogenesis and management. J Neurology 259(10):2019–2030.Google Scholar
  10. Vallez Garcia D, de Vries EF, Toyohara J et al (2015) Evaluation of [(11)C]CB184 for imaging and quantification of TSPO overexpression in a rat model of herpes encephalitis. European journal of nuclear medicine and molecular imaging 42(7):1106–1118Google Scholar
  11. Wong KK, Tolia B, Bohnen N (2008) Chronic sequelae of herpes simplex encephalitis demonstrated on interictal F-18 FDG PET/CT. Clinical nuclear medicine 33(6):443–444Google Scholar

Copyright information

© Journal of NeuroVirology, Inc. 2019

Authors and Affiliations

  1. 1.Department of Neurology, Brigham and Women’s HospitalHarvard Medical SchoolBostonUSA
  2. 2.Department of Pathology, Brigham and Women’s HospitalHarvard Medical SchoolBostonUSA

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