NT-proBNP course during MIS-C post-COVID-19: an observational study

Area of Science:

• Pediatric Cardiology
• Pediatric Critical Care
• Biomarkers in Inflammation

Background:

• Multisystem inflammatory syndrome in children (MIS-C) is a severe condition requiring accurate diagnosis and monitoring.
• N-terminal pro-B-type natriuretic peptide (NT-proBNP) is a key biomarker for MIS-C diagnosis, severity assessment, and predicting complications like cardiogenic shock.
• Existing NT-proBNP cut-offs for MIS-C vary, necessitating further investigation into its dynamic behavior.

Purpose of the Study:

• To analyze the temporal changes in NT-proBNP levels during the course of MIS-C.
• To compare NT-proBNP values based on the timing of sample collection relative to symptom onset and diagnosis.
• To describe the NT-proBNP trajectory following diagnosis and treatment initiation in pediatric patients.

Main Methods:

• Retrospective analysis of NT-proBNP levels from a single-center cohort of 37 children diagnosed with MIS-C between May 2020 and April 2023.
• Inclusion of data on the time from first symptom to diagnosis and timing of all available NT-proBNP samples.
• Comparison of NT-proBNP levels at different time points (3 vs. 6 days from symptom onset) and analysis of the rate of NT-proBNP decline post-diagnosis based on initial levels and fever duration.

Main Results:

• NT-proBNP levels significantly increased with time until MIS-C diagnosis, being higher at 6 days compared to 3 days from symptom onset.
• Following diagnosis, a 50% decrease in NT-proBNP occurred faster in children with high initial NT-proBNP (>11,000 pg/mL) (1.8 days) than in those with lower levels (3.0 days).
• The NT-proBNP decline was slower in children with persistent fever beyond 48 hours (3.6 days) compared to those whose fever resolved earlier (1.8 days).

Conclusions:

• NT-proBNP levels dynamically increase until MIS-C diagnosis and treatment initiation.
• The rate of NT-proBNP decrease post-treatment is influenced by baseline NT-proBNP levels and the presence of persistent fever.
• These findings highlight the importance of considering the timing of NT-proBNP measurements and patient-specific factors for accurate MIS-C management.