Acute Childhood Encephalitis at 2 Tertiary Care Children's Hospitals in Israel: Etiology and Clinical Characteristics

Etiological and Clinical Profile of Acute Nonbacterial Encephalitis in Children: A Single-Center Prospective Study

Encephalitis is a serious neurological syndrome caused by inflammation of the brain. The diagnosis can be challenging and etiology remains unidentified in about half of the pediatric cases. We aimed to investigate demographic, clinical, laboratory, electroencephalographic and neuroimaging findings, and outcome of acute encephalitis of nonbacterial etiology. This prospective study included children hospitalized with the diagnosis of acute encephalitis between 2017 and 2019. Microbiological investigations of the cerebrospinal fluid (CSF) were recorded. All CSF specimens were tested for anti-N methyl D-aspartate receptor (NMDAR) antibodies. In total, 31 children aged 10 months to 17 years (median = 6 years) were included. Pathogens were confirmed in CSF in three patients (9.7%): varicella zoster virus, herpes simplex virus type 1 (HSV-1), and both HSV-1 and NMDAR antibodies. Presenting features included encephalopathy (100%), fever (80.6%), seizure (45.2%), focal neurological signs (29%), and ataxia (19.4%). On clinical follow-up of median 9 (6-24) months, six patients showed neurological deficits: together with two patients who died in hospital, total eight (25.8%) patients were considered to have unfavorable outcome. Need for intubation, receiving immunomodulatory treatment, prolonged hospitalization, and high erythrocyte sedimentation rate at admission were associated with unfavorable outcome. The etiology of encephalitis remains unexplained in the majority of children. HSV-1 is the most frequently detected virus, consistent with the literature. The fact that anti-NMDAR encephalitis was detected in one child suggests autoimmune encephalitis not being rare in our center. The outcome is favorable in the majority while about one-fifth of cases suffer from sequelae.

Diagnosis and Therapy of Infectious Encephalitis in Children: A Ten-Years Retrospective Study

BACKGROUND

Infectious encephalitis represents a rare but potentially severe clinical condition. However, limited international data are available in pediatric age.

METHODS

We conducted a retrospective study to review (a) the clinical presentation; (b) laboratory, radiology, and neurophysiology findings; (c) the correlations between these exams and outcome; and (d) the therapy performed.

RESULTS

Fifty-six patients were enrolled [22 female (39.6%), mean age 4.7 years, IQR 0.7-8.7 years], 19.6% presented neurologic sequelae. HSV was the single most frequently isolated pathogen (19.6%), although in most cases, the etiology remained undefined. 41.1% children presented prodromal before the development of neurologic signs. Fever was the most frequent constitutional symptom (83.9% of cases). Cerebrospinal fluid was normal in 48.5% of cases and electroencephalograpy in 24.5% cases. Brain computed tomography scans was normal in 33 (91.7%) cases, while cerebral magnetic resonance imaging (MRI) showed pathologic findings in 62.5% of cases. MRI was the only parameter associated with neurologic sequalae [P = 0.01; OR, 8.1 (95% CI: 1.52-42.84)].

CONCLUSIONS

Pediatric encephalitis is a heterogeneous entity with nonspecific clinical and laboratory findings, with undefined etiologies in most times. MRI can play a primary role, both on a diagnostic and prognostic point-of-view, and its role should be implemented and made more accessible. Further studies are needed to define the exact role and timing of steroids.

Acute Childhood Viral Encephalitis in Southern Brazil

BACKGROUND

Viral meningoencephalitis is highly heterogeneous, varying by geographic location. The aim of this study was to characterize the etiology and reporting the clinical findings and outcome of viral encephalitis in children in southern Brazil.

METHODS

A cross-Sectional study was conducted at Hospital Pequeno Príncipe, Curitiba, Brazil, between January 2013 and December 2017. It included patients younger than 18 years, who fulfilled the criteria: altered mental status as a major criteria and 2 or more minor criteria (1) fever, (2) seizures, (3) focal neurologic findings, (4) central system fluid white cell count of ≥5 cells/mm, (5) abnormal brain imaging, and/or (6) electroencephalogram abnormalities.

RESULTS

Viral meningoencephalitis was diagnosed in 270 children, with median age of 2 years (interquartile range: 0-4), The etiology of viral meningoencephalitis was confirmed in 47% of patients. Enterovirus (18%) was the major cause of encephalitis in Southern Brazilian children, and a high prevalence of Epstein-Barr virus (6%) was demonstrated. Most patients presented with fever (81%), followed by vomiting (50%), focal neurologic findings (46%), seizures (31%) and headache (30%). Few abnormalities were detected on electroencephalograms and brain magnetic resonance images. On discharge from hospital, symptoms resolved completely in 87% of children. Sequelae were mainly observed in patients with focal neurologic symptoms (P<0.001), presence of seizures (P<0.001) and electroencephalogram abnormalities (P=0.024).

CONCLUSIONS

Enterovirus was the major cause of encephalitis. Etiologic agent of encephalitis seems to be influenced by the local virologic pattern. A poor outcome was identified in patients with seizures, focal neurologic findings and electroencephalogram abnormalities.