Immune System Dysfunction Criteria in Critically Ill Children: The PODIUM Consensus Conference

Area of Science:

• Pediatric critical care medicine
• Immunology
• Clinical diagnostics

Background:

• Immune system dysfunction is inadequately represented in current pediatric organ dysfunction definitions.
• Accurate diagnosis of immune dysfunction in critically ill children is crucial for improved outcomes.

Purpose of the Study:

• To evaluate evidence for criteria defining immune system dysfunction in critically ill children.
• To develop consensus criteria for diagnosing immune system dysfunction in this population.

Main Methods:

• Systematic electronic literature searches of PubMed and Embase (1992-2020).
• Inclusion of studies on critically ill children with measurable leukocyte abnormalities and patient-centered outcomes.
• Exclusion of adult studies, premature infants, animal studies, reviews, and case series.

Main Results:

• Identified five key criteria for immune system dysfunction:
• Peripheral absolute neutrophil count <500 cells/μL
• Peripheral absolute lymphocyte count <1000 cells/μL
• Reduced CD4+ lymphocyte count or percentage
• Monocyte HLA-DR expression <30%
• Decreased ex vivo TNFα production capacity.

Conclusions:

• Consensus criteria for diagnosing immune system dysfunction in critically ill children have been developed.
• These criteria aim to standardize diagnosis and potentially improve patient care.
• Further validation and research are needed for measures currently limited to research settings.