Clinico-epidemiological Study of Viral Acute Encephalitis Syndrome Cases and Comparison to Nonviral Cases in Children from Eastern India

Aetiological profile of acute encephalitis syndrome in Assam, India, during a 4-year period from 2019 to 2022

Acute encephalitis syndrome (AES) is a major public health concern in India as the aetiology remains unknown in the majority of cases with the current testing algorithm. We aimed to study the incidence of Japanese encephalitis (JE) and determine the aetiology of non-JE AES cases to develop an evidence-based testing algorithm. Cerebrospinal fluid (CSF) samples were tested for Japanese encephalitis virus by ELISA and polymerase chain reaction (PCR). Multiplex real-time PCR was done for Dengue, Chikungunya, West Nile, Zika, Enterovirus, Epstein Barr Virus, Herpes Simplex Virus, Adenovirus, Cytomegalovirus, Herpesvirus 6, Parechovirus, Parvovirus B19, Varicella Zoster Virus, Scrub typhus, Rickettsia species, Leptospira, Salmonella species, Streptococcus pneumoniae, Haemophilus influenzae, Neisseria meningitidis, Plasmodium species and by ELISA for Mumps and Measles virus. Of the 3173 CSF samples, 461 (14.5%) were positive for JE. Of the 334 non-JE AES cases, 66.2% viz. Scrub typhus (25.7%), Mumps (19.5%), Measles (4.2%), Parvovirus B19 (3.9%) Plasmodium (2.7%), HSV 1 and 2 (2.4%), EBV and Streptococcus pneumoniae (2.1% each), Salmonella and HHV 6 (1.2% each) were predominant. Hence, an improved surveillance system and our suggested expanded testing algorithm can improve the diagnosis of potentially treatable infectious agents of AES in India.

The Worldwide Prevalence of Herpes Simplex Virus Encephalitis and Meningitis: A Systematic Review and Meta-Analysis

Given the relatively high frequency of central nervous system infections and considerable mor- tality and morbidity reported to be caused by herpes simplex viruses among the other viral agents, having a clear knowledge about their epidemiological profile seems necessary. This systematic review and meta-analysis aimed to determine the relative frequency and preva- lence of herpes simplex encephalitis and meningitis in patients tested for viral etiologies. A comprehensive systematic review was performed in PubMed, Scopus, and Web of Science databases, searching for studies on the prevalence and relative frequency of herpes sim- plex virus 1 and herpes simplex virus 2 encephalitis and meningitis. Seventy-one studies were included. Overall, the prevalence of herpes simplex virus encephalitis among patients tested was 8% (95% confidence interval, 6%-11%; I2 = 98%) and the prevalence of herpes simplex virus meningitis among aseptic patients tested was 4% (95% confidence interval, 3%-7%; I2 = 95%), and a significant difference was observed by region. The results of our subgroup analysis for herpes simplex virus encephalitis revealed a prevalence of 8% for pediatric patients and ado- lescents and 12% for adults. The results for herpes simplex virus meningitis showed a prevalence of 4% for pediatric patients and adolescents and 9% for adults. We observed significant differ- ences in the frequency of herpes simplex virus 1 and herpes simplex virus 2 detection rates by region. Having high rates of missed cases due to inadequate, highly sensitive paraclinical tests performed on patients with suspected viral central nervous system infection is one of the pos- sible factors. More studies are needed to detect the possible flaws in the process of diagnosis in different regions.

Profile of Acute Encephalitis Syndrome Patients from South India

Introduction

Encephalitis is a major public health problem worldwide that causes huge emotional and economic loss to humanity. Encephalitis, being a serious illness, affects people of all ages. The aim is to describe the sociodemographic, clinical, etiological, and neuroimaging profile among 101 acute encephalitis syndrome (AES) patients visiting a tertiary neuro-specialty care hospital in India.

Methods

Record review of medical records of all patients attending neurology emergency and outpatient services at NIMHANS Hospital, diagnosed with AES in 2019, was conducted. Data were collected using standardized data collection forms for all cases in the study. Descriptive analyses (mean and standard deviation for continuous variables and proportions for categorical variables) were conducted. The Chi-square test/Fisher's exact test was used for the comparison of independent groups for categorical variables, and t-test for comparing means for continuous variables.

Results

About 42.6% of AES patients had viral etiology, while in 57.4%, etiology was not ascertained. Common presenting symptoms were fever (96%), altered sensorium (64.4%), seizures (70.3%), headache (42.6%), and vomiting (27.7%). Herpes simplex was the most common (21.8%) identified viral encephalitis, followed by chikungunya (5%), arboviruses (chikungunya and dengue) (4%), Japanese encephalitis (4%), rabies (3%), dengue (1%), and varicella virus (1%). About 40% of AES patients showed cerebrospinal fluid pleocytosis (44%), increased protein (39.6%), abnormal computed tomography brain (44.6%), and magnetic resonance imaging abnormalities (41.6%).

Conclusion

The study highlights the need to ascertain etiology and importance of evidence-based management of AES patients. A better understanding of opportunities and limitations in the management and implementation of standard laboratory and diagnostic algorithms can favor better diagnosis and management of AES.

An Observational Study on Pattern of Empirical Acyclovir Therapy in Children With Acute Encephalitis From Northern India

OBJECTIVES

To identify the prevalence of herpes simplex encephalitis (HSE), factors influencing the duration of empirical acyclovir and frequency of acute kidney injury (AKI) in children with acute encephalitis syndrome (AES).

DESIGN

Prospective observational study.

SETTING

Pediatric Emergency Department and PICU of a tertiary hospital in Northern India.

PATIENTS

All consecutive, eligible children between 1 month and 12 years old presenting with AES, defined as altered consciousness for greater than 24 hours (including lethargy, irritability, or a change in personality) and two or more of the following signs: 1) fever (temperature ≥ 38°C) during the current illness, 2) seizures or focal neurological signs, 3) cerebrospinal fluid (CSF) pleocytosis, 4) electroencephalogram, and/or 5) neuroimaging suggesting encephalitis, who received at least one dose of acyclovir.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Of the 101 children screened, 83 were enrolled. The median (interquartile range [IQR]) age was 3 years (1-6 yr). Thirty-one children (37.3%) were diagnosed with AES, of which four were labeled as probable HSE (three based on MRI brain, one based on serology). Scrub typhus, dengue, Japanese encephalitis, and mumps were the other infective causes. The median (IQR) duration of acyclovir therapy was 72 hours (24-264 hr); 21 children (25.3%) received acyclovir for less than 24 hours and 11 (13.3%) for greater than or equal to 14 days. New-onset AKI was seen in 18 children (21.7%) but was mostly transient. Death ( n = 8, 9.6%) and discontinuation of care due to futility or other reasons ( n = 15, 18%) were noted in 23 children (28%). Factors associated with duration of acyclovir greater than 7 days, on univariable analysis, were lower modified Glasgow Coma Score at admission, requirement of invasive ventilation, invasive intracranial pressure monitoring, and CSF pleocytosis (5-500 cells). On multivariable analysis, only CSF pleocytosis of 5-500 cells was associated with duration of acyclovir greater than 7 days.

CONCLUSIONS

Given the low prevalence of HSE, and the risk of AKI, this study sensitizes the need to review our practice on initiation and stopping of empirical acyclovir in children with acute encephalitis.

Diagnosis of Indigenous Non-Malarial Vector-Borne Infections from Malaria Negative Samples from Community and Rural Hospital Surveillance in Dhalai District, Tripura, North-East India

The aetiology of non-malaria vector-borne diseases in malaria-endemic, forested, rural, and tribal-dominated areas of Dhalai, Tripura, in north-east India, was studied for the first time in the samples collected from malaria Rapid Diagnostic Kit negative febrile patients by door-to-door visits in the villages and primary health centres. Two hundred and sixty serum samples were tested for the Dengue NS1 antigen and the IgM antibodies of Dengue, Chikungunya, Scrub Typhus (ST), and Japanese Encephalitis (JE) during April 2019–March 2020. Fifteen Dengue, six JE, twelve Chikungunya, nine ST and three Leptospirosis, and mixed infections of three JE + Chikungunya, four Dengue + Chikungunya, three Dengue + JE + Chikungunya, one Dengue + Chikungunya + ST, and one Dengue + ST were found positive by IgM ELISA tests, and four for the Dengue NS1 antigen, all without any travel history. True prevalence values estimated for infections detected by Dengue IgM were 0.134 (95% CI: 0.08–0.2), Chikungunya were 0.084 (95% CI: 0.05–0.13), Scrub were 0.043 (95% CI: 0.01–0.09), and Japanese Encephalitis were 0.045 (95% CI: 0.02–0.09). Dengue and Chikungunya were associated significantly more with a younger age. There was a lack of a defined set of symptoms for any of the Dengue, Chikungunya, JE or ST infections, as indicated by the k-modes cluster analysis. Interestingly, most of these symptoms have an overlapping set with malaria; thereby, it becomes imperative that malaria and these non-malaria vector-borne disease diagnoses are made in a coordinated manner. Findings from this study call for advances in routine diagnostic procedures and the development of a protocol that can accommodate, currently, in practicing the rapid diagnosis of malaria and other vector-borne diseases, which is doable even in the resource-poor settings of rural hospitals and during community fever surveillance.

Cerebrospinal Fluid and Serum C-Reactive Protein among Children with Acute Encephalitis Syndrome

Objectives This study aimed to evaluate the positivity of C-reactive protein (CRP) in cerebrospinal fluid (CSF) and serum in children presented with clinical diagnosis of acute encephalitis syndrome (AES).

Methods A total of 164 children between 6 months and 14 years with clinical diagnosis of AES were investigated. Qualitative CRP (slide agglutination) was determined in CSF and serum sample of each patient. On the basis of clinical examination and investigations, all the patients were divided into four groups as pyogenic meningitis, viral encephalitis, tuberculous meningitis, and cerebral malaria. The positivity of CRP in CSF and serum were compared in these groups.

Results CSF CRP was found to be positive in the majority of patients with pyogenic meningitis and a statistically significant (p ≤ 0.001) association was found between CSF CRP and final diagnosis of AES, while this association was nonsignificant (p = 0.141) in case of serum CRP. When we compared the CSF and serum CRP, serum CRP was found to be more suggestive of tuberculous meningitis, viral encephalitis, and cerebral malaria while CSF CRP was more sensitive and specific for the diagnosis of pyogenic meningitis.

Conclusion The sensitivity and specificity of CSF CRP for pyogenic meningitis was quite high. Serum CRP with a high sensitivity can be used as a screening test for different types of meningitis and cerebral malaria; however, its diagnostic accuracy has yet to be established.

Clinical Profile and Outcome of Children with Acute Central Nervous System Infection in Kerala, India

Background and aims: Infection of the central nervous system is a significant cause of morbidity and mortality in children. The aim of this study was to evaluate clinical profile and outcome of children aged 1 month to 15 years admitted with acute central nervous system infection between 2008 and 2020 in the Department of Pediatrics, Ananthapuri Hospitals and Research Institute, Thiruvananthapuram, India. Materials and methods: This was a case record based retrospective study. Results: Of 62 children, 44 had meningitis and 18 had encephalitis. Most patients were in the age group 1-5 years old and males were the predominant sex (70.96%). Eighteen patients with meningitis had a clinical triad of fever, headache, and vomiting, while only three with encephalitis experienced this. Seizures and altered sensorium were seen significantly more in children with encephalitis. Cerebrospinal fluid pleocytosis was seen in significantly more patients with meningitis compared with patients with encephalitis. Aetiology for meningitis included pneumococcus, Orientia tsutsugamushi (scrub typhus), meningococcus, and Angiostrongylus cantonensis infection. Causes of encephalitis included enterovirus, mumps virus, herpes simplex virus, dengue virus, and H1N1 influenza virus infection. Paediatric intensive care unit admission was more common for patients with encephalitis. One child with pneumococcal meningitis and another with dengue encephalitis died. Seizures were the most common sequelae. Conclusion: Typical clinical features were not present in most patients with meningitis; therefore, a high index of suspicion is needed for early diagnosis. Exact aetiologies could not be identified in most of the patients. Pneumococcus, scrub typhus, and meningococcus were the aetiological agents identified for meningitis. Encephalitis was attributed to dengue virus, herpes simplex virus, enterovirus, mumps virus, and H1N1 influenza virus infection.

Clinical Feature and Outcome of Childhood Status Epilepticus in a Teaching Hospital, Odisha, India

Objectives

The main aim is to find out the clinical feature and outcome of status epilepticus (SE) in children managed in a teaching hospital. The secondary aim is to identify the risk factors influencing the adverse outcomes.

Methods

In this prospective cohort, children aged 1 month to 14 years with SE as per the International League Against Epilepsy’s new guideline (2016) who presented to the emergency department during the period of November 2017 to October 2019 were enrolled. Clinical profile, treatment, and outcome of cases (n = 94) were noted.

Results

The majority of children, 60 (63.82%), were less than five years of age. Prior history of seizures was present in 33 (35.1%) cases, whereas 61 (64.9%) cases presented with SE as the first episode of seizure. In 14 (42.4%) previous seizure cases, SE was due to drug default. No response to first-line antiepileptic drug (AED) was seen in 84 (89.37%) cases. Acute symptomatic etiology was the commonest etiology of SE in 64 (68%) cases, of which neuro-infections accounted for 44 (46.80%) cases. Longer duration (>60 minutes) of status (p < 0.01), ventilator support (p < 0.0001), and circulatory impairment (p < 0.0001) were attributable risk factors for mortality. A total of 28 children died (mortality rate, 29.8%), and 11 showed the persistence of their neuro-deficit.

Conclusions

Neuro-infection is the most common etiology of SE in children. Longer duration of SE, more lag time for receiving the first AED, respiratory failure, and presence of shock are independent predictors for poor outcome. Hence, cessation of convulsion at the earliest leads to improved outcomes.