Experience in the Use of Body Plethysmography and Exhaled Nitric Oxide Analysis in the Diagnosis of Respiratory Disorders in Children

This article presents the experience of using body plethysmography and fractional exhaled nitric oxide (FeNO) analysis in the diagnosis of respiratory disorders in children. The aim of the study is to evaluate the clinical relevance of these methods in cases with atypical or diagnostically challenging presentations of bronchial asthma. Since 2024, FeNO testing has become available in the pulmonology department, while body plethysmography is performed under contract at a specialized clinic. A total of 50 children underwent FeNO testing, and 11 patients additionally underwent body plethysmography. Three clinical cases are analyzed to illustrate the diagnostic value of modern techniques. In a 13-year-old patient with chronic cough and no typical spirometric signs of asthma, body plethysmography enabled the first detection of reversible bronchial obstruction. In a 9-year-old girl with severe bronchial obstruction syndrome and inconclusive functional tests, an elevated FeNO level indicated eosinophilic inflammation and confirmed the allergic phenotype of asthma, justifying the initiation of genetically engineered biological therapy. In a 10-year-old child with a history of bronchopulmonary dysplasia, FeNO testing and normal functional respiratory parameters ruled out bronchial asthma and confirmed a post-infectious cause of the cough. The results emphasize the relevance and clinical significance of FeNO and body plethysmography in pediatric practice when assessing children with ambiguous respiratory symptoms. The use of these methods contributes to accurate diagnosis, phenotype verification, and personalized treatment approaches.