Encephalitis in HIV-negative immunodeficient patients: a prospective multicentre study, France, 2016 to 2019.

BackgroundData on infectious encephalitis in immunodeficient (ID) individuals are scarce. This population may present with atypical clinical symptoms, be infected by uncommon pathogens and develop poor outcomes.AimWe aimed to describe the epidemiology of infectious encephalitis among HIV-negative ID patients.MethodsPatients from the ENCEIF (Etude Nationale de Cohorte des Encéphalites Infectieuses en France) prospective cohort meeting criteria for infectious encephalitis between January 2016 and December 2019 were included. We compared clinical presentation, magnetic resonance imaging (MRI) results, biological results, infection causes and outcome of ID patients with immunocompetent (IC) patients using Pearson's chi-squared test and Student's t-test. We carried out logistic regression to assess the role of immunodeficiency as risk factor for poor outcome.ResultsID patients (n = 58) were older (mean 72 vs 59 years), had higher prevalence of diabetes (26% vs 12%), pre-existing neurological disorders (12% vs 5%) and higher case-fatality rate (23.6% vs 5.6%) compared to IC patients (n = 436). Varicella zoster virus was the primary cause of encephalitis in ID patients (this aetiology was more frequent in ID (25.9%) than in IC patients (11.5%)), with herpes simplex virus second (22.4% in ID patients vs 27.3% in IC patients). Immunodeficiency was an independent risk factor for death or major sequelae (odds ratio: 3.41, 95%CI: 1.70-6.85).ConclusionsVaricella zoster virus is the most frequent cause of infectious encephalitis in ID patients. Immunodeficiency is a major risk factor for poor outcome. ID encephalitis patients should benefit from stringent investigation of cause and early empiric treatment.

Latent human herpesvirus 6 is reactivated in CAR T cells.

Cell therapies have yielded durable clinical benefits for patients with cancer, but the risks associated with the development of therapies from manipulated human cells are understudied. For example, we lack a comprehensive understanding of the mechanisms of toxicities observed in patients receiving T cell therapies, including recent reports of encephalitis caused by reactivation of human herpesvirus 6 (HHV-6)1. Here, through petabase-scale viral genomics mining, we examine the landscape of human latent viral reactivation and demonstrate that HHV-6B can become reactivated in cultures of human CD4+ T cells. Using single-cell sequencing, we identify a rare population of HHV-6 'super-expressors' (about 1 in 300-10,000 cells) that possess high viral transcriptional activity, among research-grade allogeneic chimeric antigen receptor (CAR) T cells. By analysing single-cell sequencing data from patients receiving cell therapy products that are approved by the US Food and Drug Administration2 or are in clinical studies3-5, we identify the presence of HHV-6-super-expressor CAR T cells in patients in vivo. Together, the findings of our study demonstrate the utility of comprehensive genomics analyses in implicating cell therapy products as a potential source contributing to the lytic HHV-6 infection that has been reported in clinical trials1,6-8 and may influence the design and production of autologous and allogeneic cell therapies.

Infectious encephalitis in elderly patients: a prospective multicentre observational study in France 2016-2019.

PURPOSE: Data on encephalitis in elderly patients are scarce. We aimed to describe the characteristics, aetiologies, management, and outcome of encephalitis in patients older than 65 years. METHODS: We performed an ancillary study of ENCEIF, a prospective cohort that enrolled all cases of encephalitis managed in 46 clinical sites in France during years 2016-2019. Cases were categorized in three age groups: (1) 18-64; (2) 65-79; (3) ≥ 80 years. RESULTS: Of the 494 adults with encephalitis enrolled, 258 (52%) were ≥ 65 years, including 74 (15%) ≥ 80 years. Patients ≥ 65 years were more likely to present with coma, impaired consciousness, confusion, aphasia, and rash, but less likely to present with fever, and headache (P < 0.05 for each). Median cerebrospinal fluid (CSF) white cells count was 61/mm3[13-220] in 65-79 years, 62 [17-180] in ≥ 80 years, vs. 114 [34-302] in < 65 years (P = 0.01). The proportion of cases due to Listeria monocytogenes and VZV increased after 65 years (P < 0.001), while the proportion of tick-borne encephalitis and Mycobacterium tuberculosis decreased with age (P < 0.05 for each). In-hospital mortality was 6/234 (3%) in < 65 years, 18/183 (10%) in 65-79 years, and 13/73 (18%) in ≥ 80 years (P < 0.001). Age ≥ 80 years, coma on admission, CSF protein ≥ 0.8 g/L and viral encephalitis were independently predictive of 6 month mortality. CONCLUSION: Elderly patients represent > 50% of adults with encephalitis in France, with higher proportion of L. monocytogenes and VZV encephalitis, increased risk of death, and sequels. The empirical treatment currently recommended, aciclovir and amoxicillin, is appropriate for this age group.

Adrenal Crisis Presenting as Recurrent Encephalopathy Mimicking Autoimmune, Infectious Encephalitis, and Common Variable Immune Deficiency: A Case Report.

INTRODUCTION: Adrenal crisis can present with life-threatening complications and mimic autoimmune or infectious encephalitis, and common variable immune deficiency (CVID). The literature regarding the neurological complications of adrenal crisis is limited and focuses on patients who present with hypotension and electrolyte abnormalities. CASE REPORT: A 30-year-old man presented 3 times to our hospital with encephalopathy, fever, and left sided weakness with a history of multiple autoimmune diseases and prior hospitalizations for encephalopathy. During his first 2 admissions, he was normotensive and without electrolyte abnormalities. Extensive workup for infectious, paraneoplastic, seizure, metabolic, toxic, and vascular etiologies, and autoimmune encephalitis was negative. His exam returned to baseline with empiric steroid treatment, and he was discharged. He re-presented 2 months later with encephalopathy for a third admission. During this subsequent presentation, he had hyponatremia, low serum osmolality, elevated urine sodium, undetectable morning cortisol, and 21-α hydroxylase autoantibodies. A diagnosis of autoimmune adrenal insufficiency was established, he was treated with physiological doses of hydrocortisone and fludrocortisone, and improved rapidly to near baseline function. He has remained relapse-free at 4-year follow up. During all admissions, he was also found to have low immunoglobulin G levels and met criteria for CVID; however, his immunoglobin levels recovered with steroid replacement. CONCLUSION: The reported patient demonstrated some of the neurological complications of adrenal crisis which can mimic other autoimmune conditions such as CVID. The neurologist should be aware that recurrent encephalopathy from adrenal insufficiency can occur regardless of hemodynamic or electrolyte changes on typical hospital metabolic panels.

Pediatric Autoimmune Encephalitis and Its Relationship With Infection.

Autoimmune encephalitis (AE) is an increasingly recognized inflammatory disorder of the central nervous system and is most often characterized by antibodies against intracellular and neuronal surface antigens. AE is a devastating disease that may result in developmental delay or regression in children. However, the pathogenesis of AE is not clear, and immune system disorders after infection likely play an important role in AE. Many studies have reported that patients with herpes simplex virus encephalitis develop anti-N-methyl-d-aspartate receptor encephalitis after antiviral treatment. It is critical to recognize pediatric AE early and to distinguish it from infectious forms because AE is treatable and responsive to immunotherapies. In this review, we discuss the clinical features of pediatric AE and focus on the relationship between AE and postinfection status. In addition, we review the probable mechanisms underlying infection-triggered AE, which include molecular mimicry, bystander activation, epitope spreading, immune system disorder, and genetic susceptibility.

Clinical significance of Epstein-Barr virus in the cerebrospinal fluid of immunocompetent patients.

INTRODUCTION: Polymerase chain reaction (PCR)-based testing of cerebrospinal fluid (CSF) samples has greatly facilitated the diagnosis of central nervous system (CNS) infections. However, the clinical significance of Epstein-Barr virus (EBV) DNA in CSF of individuals with suspected CNS infection remains unclear. We wanted to gain a better understanding of EBV as an infectious agent in immunocompetent patients with CNS disorders. METHODS: We identified cases of EBV-associated CNS infections and reviewed their clinical and laboratory characteristics. The study population was drawn from patients with EBV PCR positivity in CSF who visited Pusan National University Hospital between 2010 and 2019. RESULTS: Of the 780 CSF samples examined during the 10-year study period, 42 (5.4 %) were positive for EBV DNA; 9 of the patients (21.4 %) were diagnosed with non-CNS infectious diseases, such as optic neuritis, Guillain-Barré syndrome, and idiopathic intracranial hypotension, and the other 33 cases were classified as CNS infections (22 as encephalitis and 11 as meningitis). Intensive care unit admission (13/33 patients, 39.3 %) and presence of severe neurological sequelae at discharge (8/33 patients, 24.2 %) were relatively frequent. In 10 patients (30.3 %), the following pathogens were detected in CSF in addition to EBV: varicella-zoster virus (n = 3), cytomegalovirus (n = 2), herpes simplex virus 1 (n = 1), herpes simplex virus 2 (n = 1), Streptococcus pneumomiae (n = 2), and Enterococcus faecalis (n = 1). The EBV-only group (n = 23) and the co-infection group (n = 10) did not differ in age, gender, laboratory data, results of brain imaging studies, clinical manifestations, or prognosis; however, the co-infected patients had higher CSF protein levels. CONCLUSION: EBV DNA in CSF is occasionally found in the immunocompetent population; the virus was commonly associated with encephalitis and poor prognosis, and frequently found together with other microbes in CSF.

Sequential infection of Epstein-Barr virus and cryptococcal encephalitis after umbilical cord blood transplantation in a child with X-linked adrenoleukodystrophy.

Dual infection with two pathogens can be found in few cases of encephalitis. Cases of sequential infection with EBV and cryptococcal encephalitis in post-transplant patients are rare. We describe a 5-year-old boy with X-linked adrenoleukodystrophy who presented sequential infection with EBV and cryptococcal encephalitis after umbilical cord blood transplant. The patient showed fever, vomiting and emotional agitation with EBV DNA detected in CSF on day 100. The child underwent 3 doses of intravenous rituximab with a good response. However, the child presented with right facial paralysis, headache, and fever on day 130 after 2 weeks of clinical stability. Brain MRI demonstrated chronic granuloma formed with ring enhancement. FilmArray ME PCR confirmed the existence of Cryptococcus neoformans/gattii in the CSF. The child underwent sequential treatment with amphotericin liposome B and flucytosine. Maintenance treatment with fluconazole was administered for 1 year. Facial paralysis was on longer present on day 260. Cryptococcus neoformans/gattii was not detected on day 310. The biochemistry and cell count of the CSF were completely normal on day 520. Follow-up 2.5 years after presentation, brain MRI changes showed near complete resolution of the lesions. The child survived for 3 years to the last following-up. Invasive cryptococcal encephalitis is rare and life-threatening complication of transplantation. It is important to recognize dual infections, and perform treatment quickly to improve the prognosis of encephalitis after transplantation.

From Severe Herpes Zoster to Rare Suid Herpesvirus Encephalitis: A New Twist of the Varicellovirus Genus Infection in Patients with Kidney Diseases.

Both the herpes zoster virus and suid herpesvirus type 1 (SuHV-1) belong to the Varicellovirus genus of the α-herpesviridae subfamily. They may cause opportunistic infections especially in patients with kidney diseases, varying from latent illness to overt lethality. Under these circumstances, impaired renal function is both the culprit for and victim of the infection. However, fulminant eruption of severe skin herpes zoster in lupus nephritis (LN) patients under prolonged immunosuppressive therapy is rare and even more rarely seen is the SuHV-1 encephalitis in human. Facing the evolution of these rare infections, we hence chose to review the clinical pathogenicity of these two viruses which were cognate in origin but distinct in virulence. As such, we began with the first of the two above viral diseases and proceeded with peculiar renal involvement, unique clinical symptoms and pertinent lethal risk. Of importance, LN was used to exemplify the reciprocally detrimental interactions between impaired renal function and suppressed immune response. Then in a manner similar to the gradient overlay, SuHV-1 encephalitis was discussed focusing on its neurotropic features, specific MRI findings and exclusive test of high throughput sequencing. Our report highlighted novel presentations of the Varicellovirus genus infection by providing a productive multidisciplinary communication with pointed disclosure of the renal involvement. It may therefore be of great medical relevance and educational value for clinicians, especially the unseasoned ones, to foresee and manage similar cases in susceptible patients.

Infection-Associated Opsoclonus: A Retrospective Case Record Analysis and Review of Literature.

Opsoclonus, an uncommon clinical sign, and is often described in the context of opsoclonus myoclonus ataxia syndrome (OMAS). OMAS may be paraneoplastic or postinfectious. However, opsoclonus with or without OMAS may occur in association with a wide gamut of infections. Infection-associated opsoclonus/OMAS (IAO) needs recognition as a separate entity, since it demands relatively brief immunosuppression, symptomatic treatment, and has a better outcome. Case records of children, who presented with opsoclonus to a tertiary-care teaching hospital of North India over a period of 1 year (2017-2018), were reviewed. Those with opsoclonus in the setting of an acute infection/febrile illness (symptomatic opsoclonus; IAO) were included. Of 15 children with opsoclonus, 6 children [median age: 42 months (range: 8 months to 7 years); 2 boys] had opsoclonus associated with an infective or febrile illness. Additional clinical findings in these children included myoclonus (n = 2), ataxia (n = 4) and behavioral abnormalities (n = 4). All these patients had an associated neurologic or nonneurologic illness- scrub typhus (n = 1), tuberculous meningitis (n = 1), mumps encephalitis (n = 1), brainstem encephalitis (n = 1), acute cerebellitis (n = 1), and subacute sclerosing panencephalitis (SSPE, n = 1). Children with acute cerebellitis, brainstem encephalitis, and mumps encephalitis were treated with steroids while those with scrub typhus, tuberculosis, and SSPE were treated with antibiotics, antitubercular therapy, and Isoprinosine, respectively. None of them needed long-term maintenance immunotherapy. The evaluation for tumor was negative in all. Three of the 6 children are functionally normal at the last follow-up. Acute neuro infections may trigger opsoclonus. A careful analysis of clinical data and suitable investigations can help differentiate these children from those with OMAS. This distinction may avoid unwarranted long-term immunosuppression.

A Probable Case of Recurrent Bickerstaff Brainstem Encephalitis With Fulminant Course in a Pediatric Patient.

INTRODUCTION: Bickerstaff brainstem encephalitis is a rare, often postinfectious, syndrome characterized by the clinical triad of ophthalmoplegia, ataxia, and altered consciousness. Here, we present a probable case of recurrent, pediatric Bickerstaff encephalitis, whereby the patient acutely developed loss of consciousness and eventually brain death despite optimal management. CASE REPORT: A 3-year-old male patient initially presented to the emergency department with progressive ataxia, following history of upper respiratory tract infection. He deteriorated within 12 hours of hospitalization, requiring cardiopulmonary resuscitation. The patient had decreased consciousness thereafter, showing minimal signs of brain activity. He was then deemed to be suffering a second episode of Bickerstaff encephalitis, the first being a year prior, and intravenous immunoglobulins were administered immediately. Magnetic resonance imaging of the brain on day 2 of admission showed signs of diffuse, bilateral encephalitis in the brainstem, thalami, and basal ganglia. Brain death was confirmed on day 11 of admission, following 2 brain death examinations. CONCLUSION: Although Bickerstaff brainstem encephalitis tends to involve the brainstem, outcomes of brain death have been rarely reported, even more so in the pediatric age group. This case report sheds light on, possibly, the first reported fatality of Bickerstaff encephalitis among children.

Immune-mediated encephalitis for the infectious disease specialist.

PURPOSE OF REVIEW: Autoimmune encephalitis is increasingly recognized and must be distinguished from infectious forms of encephalitis. Moreover, physicians should be aware of infectious triggers of autoimmune encephalitis and of infectious complications associated with treatment. RECENT FINDINGS: Recent epidemiological studies suggest that the incidence of autoimmune encephalitis may rival that of infectious encephalitis. Although distinguishing autoimmune from infectious forms of encephalitis on clinical grounds can be challenging, recently proposed diagnostic criteria can provide some assistance. There has been an explosion in our knowledge of autoimmune encephalitis associated with antibodies to neuronal cell surface antigens, and two of the most common forms, anti-NMDA receptor encephalitis and anti-LGI1 encephalitis, are typically associated with distinctive clinical features. Although tumors have long been known to trigger autoimmune encephalitis, it has been recently recognized that herpes simplex encephalitis may trigger the generation of antineuronal autoantibodies resulting in an autoimmune neurologic relapse. Both first and second-line therapies for autoimmune encephalitis are associated with infectious complications, whereas emerging treatments, including anakinra and tocilizumab, may also result in increased susceptibility to certain infections. SUMMARY: The diagnosis and management of autoimmune encephalitis is complex, and awareness of diagnostic criteria and modalities, typical clinical syndromes, infectious triggers of disease, and infectious complications of therapies is critical in optimizing care for affected patients.

Neuroendoscopy for post-infective hydrocephalus in children.

The treatment of hydrocephalus has changed in recent years with better imaging and introduction of endoscopic procedures as well as enhanced shunts. Indications of endoscopic third ventriculostomy (ETV) are now more refined with better quantification of outcome. This article reviews the current state of neuroendoscopy for infective hydrocephalus in children. The roles of third ventriculostomy as a primary procedure or after shunt malfunction, endoscopic interventions in multiloculated hydrocephalus and introduction of intraventricular lavage to salvage severely infected children are evaluated.

Lethal outcome of granulomatous acanthamoebic encephalitis in a man who was human immunodeficiency virus-positive: a case report.

BACKGROUND: Acanthamoeba species can cause disseminating infections in immunocompromised individuals. CASE PRESENTATION: Here, we report a case of granulomatous acanthamoebic encephalitis with a lethal outcome in a 54-year-old German man who was human immunodeficiency virus-positive. The diagnosis was based on symptoms of progressive neurological deficits, including sensorimotor paralysis of his right leg and deteriorating alertness. Due to the rapid course and rather late diagnosis of the infection, effective treatment could not be applied and he died 12 days after hospital admission. CONCLUSIONS: To the best of our knowledge, this is the second case of granulomatous acanthamoebic encephalitis reported within Germany. Our case highlights the importance of early diagnosis of granulomatous acanthamoebic encephalitis to prevent fatal outcome.

Into Darkness and Silence: What Caused Helen Keller's Deafblindness?

In 1882, at 19 months of age, Helen Keller developed a febrile illness that left her both deaf and blind. Historical biographies attribute the illness to rubella, scarlet fever, encephalitis, or meningitis. This analysis of her illness suggests she likely had bacterial meningitis, caused by Neisseria meningitidis or possibly Haemophilus influenzae.

Disseminated toxoplasmosis in a patient with advanced acquired immunodeficiency syndrome

Extracerebral toxoplasmosis, with pulmonary involvement and shock, is a rare form of toxoplasmosis in patients with advanced AIDS. It can mimic pneumocystosis, histoplasmosis, and disseminated tuberculosis, and should be considered in the differential diagnosis of causes of respiratory failure and fulminant disease in this group of individuals, especially in areas where the Toxoplasma gondii infection is highly prevalent and in those without proper use of antimicrobial prophylaxis. We report the case of a 46-year-old male patient who presented to the emergency department with uremia, requiring urgent dialysis. During the laboratorial investigation, the patient had confirmed HIV infection, with a low CD4+ peripheral T-cell count (74 cells/µL). During hospitalization, the patient presented drug-induced hepatitis due to trimethoprim/sulfamethoxazole in a prophylactic dose, requiring interruption of this medication. On the 55th day of hospitalization, the patient developed refractory shock and died. At the autopsy, disseminated toxoplasmosis with encephalitis and severe necrotizing pneumonia were diagnosed, with numerous tachyzoites in the areas of pulmonary necrosis.

Epilepsy after cerebral infection: review of the literature and the potential for surgery.

The risk of unprovoked seizures in population-based cohorts of cerebral infection survivors is 7-8% in developed countries, rising to considerably higher rates in resource-poor countries. The main risk factors for epilepsy after cerebral infection, besides acute seizures, are infection-associated brain lesions and status epilepticus during the acute phase. Despite the high prevalence of pharmacoresistant epilepsies after cerebral infections, especially in patients with MRI-identifiable lesions, only a small minority undergoes epilepsy surgery. However, excellent surgical candidates are particularly those with a history of meningitis or encephalitis in early childhood, hippocampal sclerosis on MRI, as well as a history, seizure semiology, and EEG-findings compatible with the diagnosis of a mesial temporal lobe epilepsy syndrome. More challenging are patients with neocortical/extratemporal lobe epilepsies post cerebral infection. Finally, patients with a severe hemispheric injury with contralateral hemiparesis are candidates for hemispherectomy/hemispherotomy. This review attempts to shed some light on this frequent cause of symptomatic focal epilepsy, with an emphasis on the chances offered by epilepsy surgery.