[Plasma elastase alpha 1-proteinase inhibitor complex in children with bronchitis]

Area of Science:

• Pediatric Pulmonology
• Clinical Immunology
• Biomarker Discovery

Background:

• Bronchitis is a common respiratory illness in children, often involving inflammation.
• Accurate diagnosis and monitoring of inflammatory processes are crucial for effective treatment.
• Existing inflammatory markers may not fully capture the dynamic changes in pediatric bronchitis.

Purpose of the Study:

• To evaluate the diagnostic utility of plasma polymorphonuclear neutrophil elastase-alpha 1-proteinase inhibitor complex (E-alpha 1PI) in children with bronchitis.
• To compare E-alpha 1PI levels during acute illness versus remission.
• To assess the correlation of E-alpha 1PI with other systemic inflammatory markers.

Main Methods:

• A cohort of 107 children (6 months to 15 years) was studied, including those with recurrent bronchitis (RB), obstructive bronchitis (OB), and healthy controls (C).
• Plasma E-alpha 1PI levels were measured alongside systemic inflammatory markers like ESR, leukocyte count (L), polymorphonuclear count (PMN), alpha 1-proteinase inhibitor (alpha 1PI), and C-reactive protein (CRP).
• Measurements were taken during the acute phase (I) and a disease-free stage (II).

Main Results:

• Approximately 90% of children with bronchitis exhibited significantly elevated mean plasma E-alpha 1PI levels compared to controls (p < 0.001) during the acute phase.
• No significant correlation was found between E-alpha 1PI concentration and other analyzed inflammatory indicators.
• Elevated E-alpha 1PI was observed even in cases of neutropenia, indicating its sensitivity.

Conclusions:

• Plasma E-alpha 1PI serves as a sensitive biomarker for granulocyte activation in children experiencing acute bronchitis.
• E-alpha 1PI may be a valuable diagnostic tool for pediatric bronchitis, even when other inflammatory markers are inconclusive or in the presence of neutropenia.