This study examines changes in bradykinin levels and their clinical relevance in children with obstructive bronchitis who remain afebrile yet continue to exhibit bronchial obstruction and wheezing. Thirteen children aged 9 months to 3 years (8 girls, 5 boys) were evaluated. Despite normal ESR and CRP values, obstructive symptoms persisted. Bradykinin levels, measured by ELISA, were 2–3 times above the normal range (56.5–75.6 pg/mL). These findings highlight the pathogenic role of bradykinin in pediatric obstructive bronchitis and support its potential use as a diagnostic biochemical marker. Inhaled budesonide demonstrated noticeable clinical improvement, further implicating the kallikrein–kinin system in symptom persistence.

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