Exhaled breath analysis in childhood rheumatic disorders--a longitudinal study

Area of Science:

• Pediatric Rheumatology
• Pulmonary Medicine
• Biomarker Research

Background:

• Subclinical airway inflammation can occur in pediatric rheumatologic disorders.
• Non-invasive markers like FENO50 and dEBCpH are sought to assess this inflammation.
• Existing research on these markers in pediatric rheumatology is limited.

Purpose of the Study:

• To evaluate fraction of exhaled nitric oxide (FENO50) and deaerated exhaled breath condensate pH (dEBCpH) as non-invasive markers of subclinical airway inflammation.
• To assess the correlation of FENO50 and dEBCpH with disease activity and atopic sensitization in pediatric rheumatologic patients.
• To monitor changes in FENO50 and dEBCpH over a 12-month period.

Main Methods:

• Prospective study of 85 pediatric patients with rheumatologic disorders (JIA, CRMO, SLE, JDM, etc.).
• FENO50 and dEBCpH measurements were taken over at least 12 months.
• dEBCpH was also measured in 90 healthy controls; pulmonary function tests and atopic sensitization were assessed.

Main Results:

• Neither FENO50 nor dEBCpH correlated with disease activity.
• Elevated FENO50 levels were observed in 31% of patients, predominantly those with atopic sensitization.
• Median dEBCpH did not differ between patients and controls, but showed a slight decrease over time; FENO50 remained stable.

Conclusions:

• FENO50 and dEBCpH did not show consistent abnormalities in this cohort of pediatric rheumatologic patients with stable disease.
• Some patients exhibited abnormal values of unknown significance, warranting further investigation.
• These markers may not be reliable indicators of subclinical airway inflammation in this population.