Parechovirus Encephalitis and Neurodevelopmental Outcomes.

Area of Science:

• Pediatric Neurology
• Infectious Diseases
• Neuroscience

Background:

• Human parechovirus (HPeV) is an emerging cause of encephalitis in infants.
• Early identification and understanding of clinical features are crucial for managing HPeV encephalitis.
• The Australian Childhood Encephalitis (ACE) study provides a platform for investigating encephalitis cases.

Purpose of the Study:

• To describe the clinical characteristics of HPeV encephalitis in infants.
• To evaluate the short-term and long-term outcomes of HPeV encephalitis.
• To assess the utility of diagnostic tools in identifying HPeV encephalitis.

Main Methods:

• Prospective identification of infants with suspected encephalitis in 5 hospitals.
• Comprehensive data collection including demographics, clinical presentation, laboratory results, and imaging.
• Neurodevelopmental assessment at 12 months post-discharge using the Ages and Stages Questionnaire (ASQ).

Main Results:

• Thirteen cases of suspected HPeV encephalitis were identified; 9 confirmed.
• Confirmed cases were predominantly young, female infants with seizures and white matter diffusion restriction on MRI.
• While 3/9 showed sequelae at discharge, 5/8 infants had neurodevelopmental sequelae at 12 months, including cerebral palsy and visual impairment.

Conclusions:

• HPeV encephalitis in infants presents with specific clinical and imaging findings.
• Cranial ultrasound has limited sensitivity for detecting HPeV encephalitis.
• HPeV encephalitis is associated with significant neurodevelopmental sequelae, highlighting the need for specific diagnostic testing to avoid missed diagnoses.