Viral encephalitis: Neuropsychiatric and neurobehavioral aspects

Abstract

Viral encephalitis, a condition in which a virus infects the brain and produces an inflammatory response, affects approximately 20,000 individuals per year in the United States. The viral encephalidities include sporadic and epidemic acute viral encephalidities and subacute and chronic/progressive viral encephalitis or encephalomyelitis. In people who survive these conditions, postencephalitic impairments of elemental neurologic, cognitive, emotional, and behavioral function are common. This article will provide a brief overview of the diagnosis and acute management of acute viral infections of the central nervous system. The neurologic and neuropsychiatric features, neuropathologies, and treatments of two of the more common types of acute viral encephalitis in North America--herpes simplex encephalitis and West Nile encephalitis--will be reviewed. The current and future role of psychiatrists and neuropsychiatrists in the care and study of individuals with these conditions will be discussed.

Encephalitic Arboviruses: Emergence, Clinical Presentation, and Neuropathogenesis

“…For example, studies evaluating the rates of persistent impairment in patients previously diagnosed with WNV encephalitis via serum or cerebrospinal fluid (CSF) IgM using memory (Hopkins Verbal Learning Test) and visuospatial (Rey Complex Figure Copy and Recall) tests report that 40 % to 70 % exhibit cognitive symptoms for up to 5 years after the episode of acute infection [83][84][85][86][87][88][89][90][91][92][93]. Thus, for WNV encephalitis, at a > 90 % rate of survival with~50 % incidence of cognitive disturbance, there are currently approximately 10, 000 people living with this sequelae of neuroinvasive WNV infections, with additional cases occurring at rates of 1000 to 3000 per year.…”

Psychiatric Aspects of Herpes Simplex Encephalitis, Tick-Borne Encephalitis and Herpes Zoster Encephalitis Among Immunocompetent Patients

“…Moreover, the frequently occurring neurological and psychiatric complications often result in permanent disabilities, causing a significant decrease in the patient's quality of life [2]. There are over 100 known viral causative agents of CNS infections [3]. Encephalitis may be sporadic or epidemic with regard to etiology and depending on whether it is acute, subacute, progressive or chronic [2,3].…”

“…There are over 100 known viral causative agents of CNS infections [3]. Encephalitis may be sporadic or epidemic with regard to etiology and depending on whether it is acute, subacute, progressive or chronic [2,3]. Herpes simplex virus 1 (HSV-1) is the etiologic agent in 20-52% of the cases of acute sporadic encephalitis.…”

“…Ebstein-Barr, Varicella-Zoster, rabies and West Nile viruses are less frequent agents. Arboviruses, enteroviruses and the mumps virus can cause acute epidemic encephalitis [3,4]. However, in most cases (60%) attempts to identify the pathogen causing the disease are in vain [3].…”

“…Arboviruses, enteroviruses and the mumps virus can cause acute epidemic encephalitis [3,4]. However, in most cases (60%) attempts to identify the pathogen causing the disease are in vain [3]. Cytomegalovirus, Ebstein-Barr virus and human herpes virus 6 occur more often as causative agents of encephalitis in the context of immunocompromise caused by human immunodeficiency virus (HIV) infection and post-transplant treatment [5].…”