Rinsho Shinkeigaku (Clinical Neurology)


Reactivation of latent viruses in Neurology

Tomoyo Shimada, M.D.1), Taiji Tsunemi, M.D., Ph.D.1)3), Yasushi Iimura, M.D., Ph.D.2)3), Hidenori Sugano, M.D., Ph.D.2)3) and Nobutaka Hattori, M.D., Ph.D.1)

1) Department of Neurology, Juntendo University School of Medicine
2) Department of Neurosurgery, Juntendo University School of Medicine
3) Epilepsy Center, Juntendo University School of Medicine

After establishing latent infection, some viruses can be reactivated by the alteration of host immunological conditions. First, we reviewed viruses that can cause neuronal damage by reactivation. Then we focused on the herpes simplex virus (HSV). The reactivation leads to neuronal damages through two possible mechanisms; “reactivation of a latent herpes virus” by which viruses can cause direct virus neurotoxicity, and “post-infectious immune inflammatory response” by which a focal reactivation of HSV leads to an inflammatory reaction. The former is radiologically characterized by cortical lesions, the latter is characterized by subcortical white matter lesions. We experienced a female, who underwent the right posterior quadrantectomy and then developed recurrent herpes encephalitis caused by herpes simplex reactivation, which pathologically demonstrated inflammation in the white matter, suggesting a postinfectious immune inflammatory response. The patient was successfully treated with immunosuppressants. The reactivation of the HSV is extremely rare in Japan. Neurologists should recognize this condition because this disorder will increase as epilepsy surgery gains more popularity.
Full Text of this Article in Japanese PDF (449K)

(CLINICA NEUROL, 62: 697|706, 2022)
key words: latent infection, reactivation, herpes simplex virus, herpes simplex encephalitis

(Received: 23-Dec-21)