Herpes Simplex Encephalitis Research Articles

Magnetic resonance imaging in acute meningoencephalitis of viral and unknown origin: frequent findings and prognostic potential.

Magnetic resonance imaging (MRI) findings in meningoencephalitis have mainly been described in terms of their diagnostic value rather than their prognostic potential, except for herpes simplex virus (HSV) encephalitis. The aims of our study were to describe frequency and anatomic locations of MRI abnormalities specific to limbic, circadian and motor systems in a cohort of meningoencephalitis patients, as well as to investigate the prognostic value of these MRI findings. A secondary, selective analysis of a retrospective database including all meningitis, meningoencephalitis and encephalitis cases treated between 2016 and 2018 in the University hospital of Bern, Switzerland was performed. Patients with meningitis of any cause, bacterial or autoimmune causes of encephalitis were excluded. MRI scans and clinical data from 129 meningoencephalitis cases found that the most frequent causes were tick-borne encephalitis (TBE, 42%), unknown pathogens (40%), VZV (7%), and HSV1 (5%). At discharge, median modified Rankin Score (mRS) was 3 (interquartile range, IQR, 1), 88% of patients had persisting signs and symptoms. After a median of 17 months, median Glasgow Outcome Score (GOS) was 5 (IQR 1), 39% of patients still had residual signs or symptoms. All patients with HSV, 27% with TBE and 31% of those with meningoencephalitis of unknown etiology had fluid-attenuated inversion recovery (FLAIR) and to a lesser extent diffusion-weighted imaging (DWI) lesions in their initial MRI, with highly overlapping anatomical distribution. In one fifth of TBE patients the limbic system was affected. Worse outcome was associated with presence of DWI and/or FLAIR lesions and lower normalized apparent diffusion coefficient (ADC) signal intensities. Presence of FLAIR lesions, restricted diffusion as well as the extent of ADC hypointensity in initial MRI are parameters which might be of prognostic value regarding the longterm clinical outcome for patients with meningoencephalitis of viral and of unknown origin. Although not described before, affection of limbic structures by TBE is possible as shown by our results: A substantial proportion of our TBE patients had FLAIR signal abnormalities in these regions.

A GLOBAL SCIENTOMETRIC ANALYSIS OF HERPES ENCEPHALITIS RESEARCH IN THE LAST 50 YEARS

Background: Herpes encephalitis is the most common of all encephalitis worldwide and has the highest mortality rate. The aim of this study is to review articles on this topic in order to provide a guide for future herpes encephalitis studies to assess current publishing trends and hotspots on herpes encephalitis research globally. Objective: People have been affected by the herpes virus for many years, but advances in supportive care and antiviral drugs have only recently made it possible for doctors to treat the most severe types of infections. To the authors' knowledge, however, no bibliometric analysis has been done to rate Herpes encephalitis research. In order to enhance research in this area, this study used a bibliometric analysis to assess current publishing trends and hotspots on herpes encephalitis research globally. Methods: The Web of Science database was searched for pertinent publications between January 1970 and December 2021. The research points, comprising publishing countries, affiliations, first authors, cited authors, cited references, and their clustering, as well as keyword co-occurence, were analyzed using VosViewer to identify research trends and hotspots. Results: The results of this study's search methodology revealed that between 1970 and 2021, 2138 documents. Only articles (n=1223) were included the study. 89.37% of the articles were written in English. The first article published in 1970 and most of the articles published in the years 1982, 1988, 2007, 2016, and 2017. The United States of America (USA) (29.109%), England (9.076%), France (7.441%), Japan (7.359%) and Germany (7.032) were the other top ranked countries. The most citation numbers were recorded in the year 2021. Conclusion: This bibliometric analysis outlined the general overview for Herpes encephalitis research and offered insightful guidance for continuing investigations.

Chapter 23 - Infectious leukoencephalopathies

Leukoencephalopathy from infectious agents may have a rapid course, such as human simplex virus encephalitis; however, in many diseases, it may take months or years before diagnosis, such as in subacute sclerosing panencephalitis or Whipple disease. There are wide geographic distributions and susceptible populations, including both immunocompetent and immunodeficient patients. Many infections have high mortality rates, such as John Cunningham virus and subacute sclerosing panencephalitis, although others have effective treatments if suspected and treated early, such as herpes simplex encephalitis. This chapter will describe viral, bacterial, and protozoal infections, which predominantly cause leukoencephalopathy. We focus on the clinical presentation of these infectious agents briefly covering epidemiology and subtypes of infections. Next, we detail current pathophysiologic mechanisms causing white matter injury. Diagnostic and confirmatory tests are discussed. We cover predominantly MRI imaging features of leukoencephalopathies, and in addition, summarize the common imaging features. Additionally, we detail how imaging features may be used to narrow the differential of a leukoencephalopathy clinical presentation. Lastly, we present an outline of common treatment approaches where available.

Herpes simplex encephalitis complicated with cerebral salt wasting syndrome: a case study

A 78-year-old man was admitted to the hospital with a 4-day history of fever and confusion. Physical examination revealed oral dryness and decreased skin turgor. Blood tests showed hyponatremia (121.5 ‍mEq/l), and cerebrospinal fluid examination revealed positivity for herpes simplex virus 1 (HSV-1) via polymerase chain reaction. He was diagnosed with herpes simplex encephalitis and initiated acyclovir treatment. The hyponatremia was diagnosed as cerebral salt wasting syndrome (CSWS) and treated with hypertonic saline infusion and fludrocortisone. The cerebrospinal fluid HSV-1 DNA became negative, and the serum sodium levels normalized. Hyponatremia complicated with encephalitis is often caused by the syndrome of inappropriate secretion of antidiuretic hormone (SIADH), whereas CSWS is rare, mostly observed in tuberculous meningitis. Differentiating between the SIADH and CSWS is important as they require distinct therapeutic strategies.

Deciphering Proteomic Expression in Inflammatory Disorders: A Mass Spectrometry Exploration Comparing Infectious, Noninfectious, and Traumatic Brain Injuries in Human Cerebrospinal Fluid.

The central nervous system (CNS) evokes a complex inflammatory response to injury. Inflammatory cascades are present in traumatic, infectious, and noninfectious disorders affecting the brain. It contains a mixture of pro- and anti-inflammatory reactions involving well-known proteins, but also numerous proteins less explored in these processes. The aim of this study was to explore the distinct inflammatory response in traumatic brain injury (TBI) compared with other CNS injuries by utilization of mass-spectrometry. In total, 56 patients had their cerebrospinal fluid (CSF) analyzed with the use of mass-spectrometry. Among these, CSF was collected via an external ventricular drain (EVD) from n = 21 patients with acute TBI. The resulting protein findings were then compared with CSF obtained by lumbar puncture from n = 14 patients with noninfectious CNS disorders comprising relapsing-remitting multiple sclerosis, anti-N-methyl-d-aspartate-receptor encephalitis, acute disseminated encephalomyelitis, and n = 14 patients with progressive multifocal leukoencephalopathy, herpes simplex encephalitis, and other types of viral meningitis. We also utilized n = 7 healthy controls (HCs). In the comparison between TBI and noninfectious inflammatory CNS disorders, concentrations of 55 proteins significantly differed between the groups. Among them, 23 and 32 proteins were up- and downregulated, respectively, in the TBI group. No proteins were uniquely identified in either group. In the comparison of TBI and HC, 51 proteins were significantly different, with 24 and 27 proteins being up- and downregulated, respectively, in TBI. Two proteins (fibrinogen gamma chain and transketolase) were uniquely identified in all samples of the TBI group. Also in the last comparison, TBI versus infectious inflammatory CNS disorders, 51 proteins differed between the two groups, with 19 and 32 proteins being up- and downregulated, respectively, in TBI, and no unique proteins being identified. Due to large discrepancies between the groups compared, the following proteins were selected for further deeper analysis among those being differentially regulated: APOE, CFB, CHGA, CHI3L1, C3, FCGBP, FGA, GSN, IGFBP7, LRG1, SERPINA3, SOD3, and TTR. We found distinct proteomic profiles in the CSF of TBI patients compared with HC and different disease controls, indicating a specific interplay between inflammatory factors, metabolic response, and cell integrity. In relation to primarily infectious or inflammatory disorders, unique inflammatory pathways seem to be engaged, and could potentially serve as future treatment targets.

HSV encephalitis in the context of substance abuse: A case report

HSV encephalitis in the context of substance abuse: A case report

Herpes Simplex Virus Encephalitis Complicated by Acute Ischemic Stroke

Herpes Simplex Virus Encephalitis Complicated by Acute Ischemic Stroke

The history of the Japanese Society for Neuro-infectious Diseases: Foundation, objectives, and legacy.

The Japanese Research Group for Neuro-infectious Diseases was founded in August 1996, and by 2004 it had evolved into the Japanese Society for Neuro-infectious Diseases. The Society focuses on neuroinfectious conditions (e.g., encephalitis/encephalopathy, myelitis, and meningitis), providing a venue for academic presentations and exchanges. Clinical guidelines for major neurological infectious diseases are also published by the Society, in order to meet the social demands of each era. Although the threat of herpes simplex encephalitis has declined due to acyclovir's introduction, the frequency of encephalitis or peripheral neuropathy caused by varicella-zoster virus is increasing. In Japan, prion disease, human T-cell leukemia virus-1 (HTLV-1)-associated myelopathy (HAM), subacute sclerosing panencephalitis (SSPE), and progressive multifocal leukoencephalopathy (PML) are designated as intractable diseases. The incidence of prion disease is 1.8/1,000,000 individuals, with the sporadic type accounting for 80%. Prion disease is fatal, and effective medications are awaited. HAM's prevalence is ~3/100,000 individuals, with a male-to-female ratio of 1:2-3. HAM is common in western Japan, including Kyushu and Okinawa. The prevalence of PML is rising with the spread of both immunosuppressive therapy for transplantation and treatment for multiple sclerosis. From late 2019 through 2020, the world faced a global outbreak of coronavirus disease 2019 (COVID-19) due to virus mutations, and the threat of new mutations persists. Close attention should be paid to the emergence of new neurological infections that could arise from abnormal weather patterns and/or a decline in immune function due to aging.

Preemptive strategies and lessons learned from complications encountered with microvascular decompression for hemifacial spasm.

Microvascular decompression (MVD) is the only curative treatment modality for hemifacial spasm (HFS). Although generally considered to be safe, this surgical procedure is surrounded by many risks and possible complications. The authors present the spectrum of complications that they met in their case series, the possible causes, and the strategies recommended to minimize them. The authors reviewed a prospectively maintained database for MVDs performed from 2005 until 2021 and extracted relevant data including patient demographics, offending vessel(s), operative technique, outcome, and different complications. Descriptive statistics with uni- and multivariable analyses for the factors that may influence the seventh, eighth, and lower cranial nerves were performed. Data from 420 patients were obtained. Three hundred seventeen of 344 patients (92.2%) with a minimum follow-up of 12 months had a favorable outcome. The mean follow-up (standard deviation) was 51.3 ± 38.7 months. Immediate complications reached 18.8% (79/420). Complications persisted in only 7.14% of patients (30/420) including persistent hearing deficits (5.95%) and residual facial palsy (0.95%). Temporary complications included CSF leakage (3.10%), lower cranial nerve deficits (3.57%), meningitis (0.71%), and brainstem ischemia (0.24%). One patient died because of herpes encephalitis. Statistical analyses showed that the immediate postoperative disappearance of spasms and male gender are correlated with postoperative facial palsy, whereas combined vessel compressions involving the vertebral artery (VA) and anterior inferior cerebellar artery can predict postoperative hearing deterioration. VA compressions could predict postoperative lower cranial nerve deficits. MVD is safe and effective for treating HFS with a low rate of permanent morbidity. Proper patient positioning, sharp arachnoid dissection, and endoscopic visualization under facial and auditory neurophysiological monitoring are the key points to minimize the rate of complications in MVD for HFS.

WhatsApp como ferramenta para identificação de doenças em ruminantes e equinos não diagnosticadas e subnotificadas em Mato Grosso do Sul

ABSTRACT: This study explores the use of WhatsApp as a tool for identifying previously undiagnosed and underreported diseases in ruminants and horses in Mato Grosso do Sul, Brazil. The research, carried out from January 2022 to December 2023, involved a WhatsApp group of 302 public service and private sector veterinarians. The contacts were categorized as those that resulted in a necropsy by the veterinary diagnostic laboratory, the sending of a sample for histopathological analysis, or the non-sending of material. The results demonstrate the efficiency of using WhatsApp for diagnosing underreported diseases such as anaplasmosis, haemonchosis, rabies, blackleg disease, Mannheimia haemolytica pneumonia, bovine herpesvirus encephalitis, multiple mineral deficiency in cattle and copper poisoning in sheep, thus increasing diagnostic efficiency for veterinary laboratories. The tool also facilitated communication, resulting in an increase in conclusive diagnoses, the identification of previously undiagnosed diseases such as Chlamydia pecorum encephalomyelitis in buffalo, peripheral neuropathy in cattle, phosphorus deficiency in cattle, vitamin A deficiency, and perinatal pneumonia caused by Salmonella enterica subsp. arizonae in cattle. In addition, it was possible to identify underreported occurrences, such as cases of abortion and neonatal diarrhea and to implement the correction of diagnostic approaches in real-time via WhatsApp. The study concludes that WhatsApp improves communication between field veterinarians and diagnostic laboratories, providing valuable information on disease occurrence and diagnostic challenges.

Cognitive functioning of a patient with herpes simplex virus encephalitis – a case study. An exemplary paper for the State Examination in the field of clinical psychology – neuropsychology

This paper is an example of a case report for a state examination in the field of clinical psychology – neuropsychology. The case report was used during the examination in 2023 and received a positive rating. Its publication is an attempt to respond to the still reported difficulties in accessing exemplary works of this type. Due to publication limitations, some elements of the description have been shortened. The article can also be treated as a case study on the cognitive functioning of a person with active herpes encephalitis. Both screening scales, such as Addenbrooke’s Cognitive Examination III and Frenchay Aphasia Screening Test, as well as other scales to measure individual cognitive functions were used in order to assess the patient.

The split apparent diffusion coefficient sign: A novel magnetic resonance imaging biomarker for cortical pathology with possible implications in autoimmune encephalitis.

MRI is the imaging modality of choice for assessing patients with encephalopathy. In this context, we discuss a novel biomarker, the "split ADC sign," where the cerebral cortex demonstrates restricted diffusion (high DWI signal and low ADC) and the underlying white matter demonstrates facilitated diffusion (high or low DWI signal and high ADC). We hypothesize that this sign can be used as a biomarker to suggest either acute encephalitis onset or to raise the possibility of an autoimmune etiology. A full-text radiological information system search of radiological reports was performed for all entities known to produce restricted diffusion in the cortex excluding stroke between January 2012 and June 2022. Initial MRI studies performed upon onset of clinical symptoms were screened for the split ADC sign. 25 subjects were encountered with a positive split ADC sign (15 female; median age = 57years, range 18-82). Diagnosis included six herpes simplex encephalitis, three peri-ictal MRI changes, eight PRES, two MELAS, and six autoimmune (3 anti-GABAAR, two seronegative, and one anti-Ma2/Ta). Subjects were imaged at a mean 1.8days after the onset of symptoms (range 0-8). We present a novel visual MRI biomarker, the split ADC sign, and highlight its potential usefulness in subjects with encephalopathy to suggest acute disease onset or to raise the possibility of an autoimmune etiology when location-based criteria are applied. When positive, the sign was present on the initial MRI and can therefore be used to help focus further clinical and laboratory workup.

The immunobiology of herpes simplex virus encephalitis and post-viral autoimmunity.

Herpes simplex virus encephalitis (HSE) is the leading cause of non-epidemic encephalitis in the developed world and, despite antiviral therapy, mortality and morbidity is high. The emergence of post-HSE autoimmune encephalitis reveals a new immunological paradigm in autoantibody-mediated disease. A reductionist evaluation of the immunobiological mechanisms in HSE is crucial to dissect the origins of post-viral autoimmunity and supply rational approaches to the selection of immunotherapeutics. Herein, we review the latest evidence behind the phenotypic progression and underlying immunobiology of HSE including the cytokine/chemokine environment, the role of pathogen-recognition receptors, T- and B-cell immunity and relevant inborn errors of immunity. Second, we provide a contemporary review of published patients with post-HSE autoimmune encephalitis from a combined cohort of 110 patients. Third, we integrate novel mechanisms of autoimmunization in deep cervical lymph nodes to explore hypotheses around post-HSE autoimmune encephalitis and challenge these against mechanisms of molecular mimicry and others. Finally, we explore translational concepts where neuroglial surface autoantibodies have been observed with other neuroinfectious diseases and those that generate brain damage including traumatic brain injury, ischaemic stroke and neurodegenerative disease. Overall, the clinical and immunological landscape of HSE is an important and evolving field, from which precision immunotherapeutics could soon emerge.

Citrullination profile analysis reveals peptidylarginine deaminase 3 as an HSV-1 target to dampen the activity of candidate antiviral restriction factors.

Herpes simplex virus 1 (HSV-1) is a neurotropic virus that remains latent in neuronal cell bodies but reactivates throughout an individual's life, causing severe adverse reactions, such as herpes simplex encephalitis (HSE). Recently, it has also been implicated in the etiology of Alzheimer's disease (AD). The absence of an effective vaccine and the emergence of numerous drug-resistant variants have called for the development of new antiviral agents that can tackle HSV-1 infection. Host-targeting antivirals (HTAs) have recently emerged as promising antiviral compounds that act on host-cell factors essential for viral replication. Here we show that a new class of HTAs targeting peptidylarginine deiminases (PADs), a family of calcium-dependent enzymes catalyzing protein citrullination, exhibits a marked inhibitory activity against HSV-1. Furthermore, we show that HSV-1 infection leads to enhanced protein citrullination through transcriptional activation of three PAD isoforms: PAD2, PAD3, and PAD4. Interestingly, PAD3-depletion by specific drugs or siRNAs dramatically inhibits HSV-1 replication. Finally, an analysis of the citrullinome reveals significant changes in the deimination levels of both cellular and viral proteins, with the interferon (IFN)-inducible proteins IFIT1 and IFIT2 being among the most heavily deiminated ones. As genetic depletion of IFIT1 and IFIT2 strongly enhances HSV-1 growth, we propose that viral-induced citrullination of IFIT1 and 2 is a highly efficient HSV-1 evasion mechanism from host antiviral resistance. Overall, our findings point to a crucial role of citrullination in subverting cellular responses to viral infection and demonstrate that PAD inhibitors efficiently suppress HSV-1 infection in vitro, which may provide the rationale for their repurposing as HSV-1 antiviral drugs.

Paraneoplastic Neurologic Syndromes.

Progress is ongoing in understanding paraneoplastic neurologic disorders, with new syndromes and antibodies being described and more detailed evidence available to guide workup for diagnosis and treatment to improve outcomes. Many excellent reviews have summarized the molecular features of different antibodies, but this article emphasizes the clinical features of each syndrome that may help guide initial diagnosis and treatment, which often should occur before an antibody or cancer is found to confirm the diagnosis. Recent findings include updated diagnostic criteria with validated sensitivity and specificity, discovery of novel antibodies, and clinical findings that increase the likelihood of an underlying paraneoplastic disorder. Suggestive syndromes that have been recently identified include faciobrachial dystonic seizures and pilomotor auras in anti-leucine-rich glioma inactivated protein 1 encephalitis, extreme delta brush on EEG in N-methyl-d-aspartate (NMDA)-receptor encephalitis, déjà vu aura in anti-glutamic acid decarboxylase 65 (GAD65) encephalitis, and sleep disturbances in several disorders. In addition, there is confirmed utility of brain positron emission tomography (PET) and CSF markers, including carcinoembryonic antigen and oligoclonal bands, as well as improved tests for the presence of leptomeningeal cancer cells in CSF. Associations of cancer immunotherapies with paraneoplastic syndromes and herpes simplex virus encephalitis (and COVID-19) with NMDA-receptor encephalitis have been described. All neurologists should be aware of advances regarding paraneoplastic neurologic syndromes, as patients can present with a wide variety of neurologic symptoms and earlier diagnosis and treatment can improve outcomes.

2713. Risk factors and clinical presentation of Herpes Simplex Virus Encephalitis in cancer patients

Abstract Background Herpes Simplex Virus Encephalitis (HSVE) can have lifelong sequelae. Presentation can be nonspecific in cancer patients. Cerebrospinal fluid testing may be falsely negative early in illness [1]. New immune-based or targeted radiation (RT) modalities may change risk, incidence of HSVE in cancer patients. Methods Retrospective study at Memorial Sloan Kettering Cancer Center (MSK). Review of records of patients with CSF meningitis/encephalitis (ME) PCR panels from 8/1/2016 to 7/31/2022. All unique patients who received brain RT at MSK during those dates were used to calculate incidence rates. Results 2749 patients had 5497 CSF analyses with ME panel. Of these, 12 tests from 10 patients showed HSV-1 or -2; 1 patient had relapsing HSVE and 3 positive HSV2 tests each done at least 6 months apart. Table 1 shows 10 patients with HSVE. 8 had solid tumors, 6 with receipt of chemo- or immunotherapy within 30 days. All solid tumor patients with HSVE had brain RT; 6 received steroids. 1 patient with relapsing HSVE was on immune checkpoint inhibitor (ICI). 4/8 patients with MRIs (Table 2) lacked typical findings; 4/8 patients with EEGs had focal temporal seizure activity. CSF pleocytosis was absent in 4/10 cases. 5 patients had residual deficits. 4 died due to progression of disease. Incidence of HSVE with brain radiation was 2.6/10,000 patient-years. Conclusion General population incidence of HSVE ranges from 1-4 per million population per year [2]. Those receiving cancer treatment and brain RT have elevated HSVE risk. We found the risk after brain RT is much higher: 2.6/10,000 person-years. Only 1 of 10 patients in our series made a full recovery. Other key findings include: Limitations: Disclosures Mini Kamboj, MD , ASCO: speaker fee|Medscape: speaker fee|MJH life sciences: speaker fee|Regeneron: Advisor/Consultant|Web md: speaker fee

A case of severe anterograde amnesia in the era of smartphone technology

ABSTRACT A.V. is a young herpes simplex encephalitis (HSE) survivor who suffered extensive bilateral damage to the medial temporal lobe (MTL) leading to a severe and pervasive form of anterograde amnesia. Structural Magnetic Resonance Imaging (MRI) revealed lesions that encompass the hippocampus and amygdala in both hemispheres and that extend more laterally in the right temporal lobe. At the same time, detailed neuropsychological testing showed that the disparity between A.V.’s preserved intellectual functioning (Full Scale IQ: 115) and severe memory deficit (Delayed Memory Index: 42) is one of the largest on record. Despite this deficit, A.V. has regained a higher level of functioning and autonomy compared to previously documented amnesic cases with major bilateral MTL lesions. As a millennial, one advantage which A.V. has over prior amnesic cases is fluency with digital technology – particularly the smartphone. The analysis of his phone and specific app usage showed a pattern that is consistent with the strategy to offload cognitive tasks that would normally be supported by the MTL. A.V.’s behavior is significant in terms of rehabilitation and may have broader implications at the societal level and for public health given the ubiquity of smartphone technology and its potential to become integrated with neural mnemonic functions.

Plenary E: Learning from patients: people who have changed my way of thinking

Abstract & Learning Objectives:This presentation discusses six patients with different problems, referred for rehabilitation, who challenged my views on how to apply neuropsychological principles to their treatment. We begin with Derek, who had sustained a traumatic brain injury from a gunshot wound. I was asked to reduce his weight, but he could not read or write because of the brain injury so I had to find another way to achieve the weight loss. This made me realize that neuropsychologists have to "think on their feet" and be flexible. The second patient is Kate, who developed brain stem encephalitis. Expected to die, and unable to speak, she convinced me that, however severe the injury, we should not give up and recovery can continue for many years. Kate, managed to speak intelligibly fourteen years after her illness! The next patient, Claire, a school nurse, had herpes simplex encephalitis which left her with prosopagnosia and extreme anxiety. Her story made me realize the personal consequences of prosopagnosia that is typically overlooked by most neuropsychologists. The fourth patient, Gary, was attacked by a gang while saving his father. He remained in a state of unconsciousness for 19 months and, thus, had a very poor prognosis. Nevertheless, he defied the predictions of all medical staff, woke up and did very well. The penultimate patient is Natasha, who, as far as we know is the only person in the world to have two syndromes, "Sheehans Syndrome" which is very rare in developed countries and "Sickle cell disease" which is not rare. As a result of the Sheehan's she developed Balint's Syndrome. Her case made me learn about Sheehan's Syndrome and accept that Natasha's main goal in life, was not what I expected it to be. The final patient is Paul, an opera singer, who was diagnosed with" Locked-in Syndrome" following a brain stem stroke. Not only was he a good communicator once a good system was found, but he felt he had a good quality of life by" living within his head". Although many of us feel that to be fully conscious but totally dependent on others, is a very cruel situation to be in, Paul did not feel this. All these patients taught me a great deal and I thank them for this.Upon conclusion of this course, learners will be able to: 1.Describe the main purposes of neuropsychological rehabilitation2.Discuss about six patients who challenged typical concepts about neuropsychological rehabilitation3.Gain some knowledge about Sheehan's syndrome4.Explain the three components of Balint's syndrome5.Summarize the difference between Locked-in syndrome and the minimally conscious state6.Recognize some of the anatomy associated with these syndromes

Herpes Simplex Virus Type 2 Encephalitis in an Immunocompetent Adult: A Diagnostic Challenge

Herpetic encephalitis is the most common cause of fatal sporadic encephalitis. Beyond the neonatal period, herpes simplex virus type 1 (HSV-1) is the etiologic agent in nearly all cases, with < 10% of cases attributable to HSV-2. Nevertheless, neurological infections caused by HSV-2 are responsible for significant morbidity and mortality. Therefore, it must be diagnosed and treated at an early stage. It is classically characterized by a triad of fever, headache, and behavioral changes. The association of these symptoms, laboratory tests, and imaging is fundamental for the early diagnosis and immediate treatment of this pathology to prevent its progression from being fatal. We report a rare case of HSV-2 encephalitis in a previously healthy 61-year-old man, free of genital lesions, who presented with altered mental status, fever, altered cerebrospinal fluid (CFS) with lymphocytic pleocytosis, normal brain imaging, and an initially negative CFS polymerase chain reaction for HSV-1 and HSV-2.

An imaging review of the hippocampus and its common pathologies.

The hippocampus is a complex structure located in the mesial temporal lobe that plays a critical role in cognitive and memory-related processes. The hippocampal formation consists of the dentate gyrus, hippocampus proper, and subiculum, and its importance in the neural circuitry makes it a key anatomic structure to evaluate in neuroimaging studies. Advancements in imaging techniques now allow detailed assessment of hippocampus internal architecture and signal features that has improved identification and characterization of hippocampal abnormalities. This review aims to summarize the neuroimaging features of the hippocampus and its common pathologies. It provides an overview of the hippocampal anatomy on magnetic resonance imaging and discusses how various imaging techniques can be used to assess the hippocampus. The review explores neuroimaging findings related to hippocampal variants (incomplete hippocampal inversion, sulcal remnant and choroidal fissure cysts), and pathologies of neoplastic (astrocytoma and glioma, ganglioglioma, dysembryoplastic neuroepithelial tumor, multinodular and vacuolating neuronal tumor, and metastasis), epileptic (mesial temporal sclerosis and focal cortical dysplasia), neurodegenerative (Alzheimer's disease, progressive primary aphasia, and frontotemporal dementia), infectious (Herpes simplex virus and limbic encephalitis), vascular (ischemic stroke, arteriovenous malformation, and cerebral cavernous malformations), and toxic-metabolic (transient global amnesia and opioid-associated amnestic syndrome) etiologies.