Herpes zoster-encefalitis: een diagnostische uitdaging bij de geriatrische patiënt

Herpes zoster encephalitis: a diagnostic challenge in a geriatric patient Reactivation of the varicella zoster virus (VZV) is a prevalent disease and is - in addition to the typical vesicular rash - responsible for rare neurological conditions. Older people form a major group of concern, given the increasing risk of VZV reactivation at a higher age together with a higher risk of complications. Herpes zoster encephalitis is a rare but serious complication which often presents atypically, delaying the diagnostic process. In this article, the medical history of a patient with herpes encephalitis without the typical clinical and biochemical signs of infection is presented. This patient also suffered from Ramsay Hunt syndrome, another rare complication of VZV, characterized by vesicular rash in the ear and ipsilateral peripheral facial paralysis. Both diseases are briefly reviewed and the potential benefits of vaccination are discussed.

Autoimmune Encephalitis and Autism Spectrum Disorder

The concept of “acquired autism” refers to the hypothesis that amongst the massive heterogeneity that encompasses autism spectrum disorder (ASD) there may be several phenotypes that are neither syndromic nor innate. Strong and consistent evidence has linked exposure to various pharmacological and infective agents with an elevated risk of a diagnosis of ASD including maternal valproate use, rubella and herpes encephalitis. Autoimmune encephalitis (AE) describes a group of conditions characterised by the body's immune system mounting an attack on healthy brain cells causing brain inflammation. The resultant cognitive, psychiatric and neurological symptoms that follow AE have also included ASD or autism-like traits and states. We review the current literature on AE and ASD. Drawing also on associated literature on autoimmune psychosis (AP) and preliminary evidence of a psychosis-linked subtype of ASD, we conclude that AE may either act as a potentially causative agent for ASD, and/or produce symptoms that could easily be mistaken for or misdiagnosed as autism. Further studies are required to discern the connection between AE and autism. Where autism is accompanied by regression and atypical onset patterns, it may be prudent to investigate whether a differential diagnosis of AE would be more appropriate.

Fas/FasL Contributes to HSV-1 Brain Infection and Neuroinflammation

The Fas/FasL pathway plays a key role in immune homeostasis and immune surveillance. In the central nervous system (CNS) Fas/FasL is involved in axonal outgrowth and adult neurogenesis. However, little is known about the role of the Fas/FasL pathway in herpes encephalitis. In this study, we used a neuropathogenic clinical strain of herpes simplex virus type 1 (HSV-1) to explore infection-induced inflammation and immune responses in the mouse brain and the role of Fas/FasL in antiviral CNS immunity. HSV-1 CNS infection induced the infiltration of Fas- FasL-bearing monocytes and T cells in the brain and also to an up-regulation of Fas and FasL expression on resident astrocytes and microglia within infected sites. Upon infection, Fas- and FasL-deficient mice (lpr and gld) were partially protected from encephalitis with a decreased morbidity and mortality compared to WT mice. Fas/FasL deficiency promoted cell-mediated immunity within the CNS. Fas receptor stimulation abrogated HSV-1 induced activation and inflammatory reactions in microglia from WT mice, while lack of Fas or FasL led to a more pronounced activation of monocytes and microglia and also to an enhanced differentiation of these cells into a pro-inflammatory M1 phenotype. Furthermore, the specific immune system was more efficient in Fas- and FasL-deficient mice with significantly higher numbers of infiltrating HSV-1-specific cytotoxic T cells in the brain. Our data indicate that the Fas/FasL pathway leads to excessive neuroinflammation during HSV-1 infection, which is associated with a diminished anti-viral response and an excessive neuroinflammation.

Herpes encephalitis in an elderly immunocompetent lady – A case report

Herpes zoster encephalitis is a rare complication of varicella zoster virus infection. As its clinical presentation is usually non-specific, it often goes unrecognized. Advent of polymerase chain reaction test for detecting viral particles in the cerebrospinal fluid has enabled rapid and accurate diagnosis.

When the brain slows the heart—herpes encephalitis and sinus arrest: a case report

Background Herpes simplex virus (HSV) encephalitis is a known cause of cognitive deterioration, neurological disturbances, and seizures though are rarely associated with sinus node dysfunction. Case summary We present a 54-year-old man admitted to the hospital with a 10-day history of fever, confusion, and fatigue, 1 week following a transient loss of consciousness. An initial workup suggested HSV encephalitis and the patient was started on intravenous Acyclovir. Due to his episode of syncope, a 24 h Holter electrocardiogram monitoring was performed. The Holter documented multiple episodes of sinus arrest, with a second episode of syncope noticed by the hospital staff concurrent with the last documented sinus arrest. Following antiviral treatment and resolution of the encephalitis we noticed complete resolution of sinus node dysfunction. We subsequently avoided permanent pacemaker implantation. Discussion Our case of proven HSV encephalitis complicated by sinus node arrest and syncope with complete resolution following antiviral treatment suggests no indication for permanent pacemaker implantation. This approach is consistent with data from previously reported cases.

Pediatric N-Methyl-d-Aspartate (NMDA) Receptor Encephalitis, With and Without Herpes Encephalitis

Objective: To compare clinical, diagnostic, management, and outcome factors in children with anti– N-methyl-d-aspartate receptor (NMDAR) encephalitis and a history of herpes simplex encephalitis (HSE) to children with NMDAR encephalitis without a history of HSE. Methods: All patients with anti-NMDAR antibodies in cerebrospinal fluid treated at our institution between 2012 and 2019 were identified and divided into those with a history of HSE (HSE+NMDAR group) and those without a history of HSE (NMDAR-only group). Demographic data, clinical characteristics, immunotherapy, and outcome data were collected on all patients and compared between the 2 groups. Results: Seventeen patients were identified with anti-NMDAR antibodies in cerebrospinal fluid, 6 of whom had a history of HSE. Mean age in the HSE+NMDAR cohort was significantly younger in the HSE+NMDAR cohort, as 5 of the 6 patients were infants. Of HSE+NMDAR patients, 50% had behavioral symptoms, 67% had movement disorders, and 100% had seizures at disease nadir. In the NMDAR-only group, 100% had behavioral symptoms, 73% had movement disorders, and 73% had seizures at nadir. HSE+NMDAR patients received a median of 1 immunotherapy, compared to a median of 4.5 immunotherapies in the NMDAR-only group. Conclusion: Behavioral symptoms were more common in NMDAR-only patients, whereas seizures were more common in HSE+NMDAR patients. Both groups had significant disability at disease nadir, with more improvement in disability over time in the NMDAR-only group. HSE+NMDAR patients received fewer immunotherapies than NMDAR-only patients. Outcomes of infants with HSE appear to primarily reflect sequelae from HSE.

Hemispheric encephalitis secondary to HAV

A 2-year male child, presented to National Institute of Child Health (NICH), with acute onset high grade fever and focal left sided seizures for 1 day, followed by left hemiparesis and encephalopathy. Developmental and family history was unremarkable. On physical examination, patient’s body temperature rose up to 38.7 °C. Though he had pallor along with hepatomegaly, there were no signs of jaundice or ascites. Central nervous system examination showed encephalopathy as well as positive neck stiffness. Motor system examination revealed generalized decrease in bulk of upper and lower limbs, but rest of the findings were localized to left side of the body, showing hypertonia, decreased power, brisk muscle stretch reflex, and positive ankle clonus and left Babinski sign. Blood investigations showed anemia (hemoglobin 9.1g/dl), leukocytosis (white blood cells 22.1 cells/μL) and raised aspartate aminotransferase (AST) levels (826 IU/L). Total bilirubin and direct bilirubin levels were normal (0.3 mg/dL and 0.1 mg/dL, respectively). Serum ammonia (64 μg/dL) and lactic acid (1.6 μg/dL) levels were also within normal ranges. The cerebrospinal fluid (CSF) was also clear, with 0 leukocytes/μL, protein levels of 25 mg/dL, and normal glucose levels (82 mg/dL), no organism was seen on gram stain. Hepatitis A Ig M antibody came out to be reactive. Brain computed tomography showed large hypo density along with effacement of sylvian fissure, sulci, gyri on right side involving frontal, parietal, and temporal and occipital lobe on ipsilateral side. On post contrast, there was remarkable meningeal enhancement on right side. MRI brain revealed cortical and subcortical large area of abnormal signal intensity seen in fronto-parietal and occipital cortex on the right side along with laminar necrosis. Seizures were controlled by given intravenous injection phenytoin and leviteracetam in bolus and then maintenance doses. Intravenous acyclovir was started due to clinical suspicion of herpes encephalitis but was stopped after observing clinical improvement and identification of Ig M antibody of HAV. Patient conscious level improved after 2 weeks. AST levels also decreased to 20 IU/L and he was discharged with advice to follow up after 14 days