International consensus definitions for infection-triggered encephalopathy syndromes

Area of Science:

• Neurology
• Infectious Diseases
• Pediatric Neurology

Background:

• Infection-triggered encephalopathy syndrome (ITES) lacks standardized diagnostic criteria.
• Differentiating ITES from infectious and autoimmune encephalitis is clinically challenging.

Purpose of the Study:

• To establish standardized diagnostic criteria for infection-triggered encephalopathy syndrome (ITES).
• To define five specific clinical syndromes within ITES.

Main Methods:

• International expert consensus using nominal group technique over 18 months.
• Criteria development based on existing definitions, standardized format, and rigorous review.
• Inclusion of infection/fever, encephalopathy features, MRI findings, and exclusion criteria.

Main Results:

• Consensus reached on five specific ITES subtypes: acute encephalopathy with biphasic seizures and late reduced diffusion, acute necrotizing encephalopathy, mild encephalopathy with a reversible splenial lesion, acute fulminant cerebral oedema, and acute shock with encephalopathy and multiorgan failure.
• Distinctions between ITES and key differential diagnoses, particularly autoimmune encephalitis, were clarified.
• Related epilepsy syndromes with overlapping features were discussed.

Conclusions:

• The consensus definition provides a crucial diagnostic framework for ITES.
• Improved diagnostic clarity is expected to enhance clinical awareness and facilitate international research.
• Standardized criteria will support future clinical trials and collaborative studies on ITES.