Prognostic Significance of Immune Abnormalities in Children with Severe Sepsis

Area of Science:

• Pediatric Intensive Care
• Immunology
• Infectious Diseases

Background:

• Severe sepsis in children presents a significant challenge in pediatric intensive care units (PICUs).
• Immune system dysregulation, including immunoglobulin and lymphocyte subset alterations, is implicated in sepsis outcomes.
• Understanding these immune changes is crucial for predicting mortality and guiding treatment.

Purpose of the Study:

• To assess immunoglobulin levels and lymphocyte subsets in children with severe sepsis upon PICU admission.
• To determine the correlation between these immune parameters and mortality in pediatric severe sepsis.
• To identify specific immune markers predictive of poor outcomes.

Main Methods:

• A prospective study involving 52 children diagnosed with severe sepsis or septic shock.
• Measurement of serum immunoglobulins and lymphocyte subsets at diagnosis and 3 months post-diagnosis for survivors.
• Utilized regression analysis to identify independent predictors of mortality.

Main Results:

• The most frequent immune abnormalities at admission were low Natural Killer (NK)-cell count (92%), low T-cells (40%), and low B-cells (36%).
• Elevated IgM was observed in 27% of patients, while low IgG and IgA were less common (17% and 13%, respectively).
• Low IgG levels were identified as an independent predictor of mortality (OR: 2.77; p=0.014), regardless of other factors.

Conclusions:

• Children with severe sepsis frequently exhibit immune abnormalities, including low NK-cells, elevated IgM, and reduced T-/B-cells.
• Low IgG levels at admission are a significant independent predictor of mortality in pediatric severe sepsis.
• Immune parameters generally normalized in survivors after 3 months, although some persistent lymphopenia was noted.