Quantification of Enteric Dysfunction in Cystic Fibrosis: Inter- and Intraindividual Variability

Area of Science:

• Gastroenterology
• Pulmonology
• Biomarker Discovery

Background:

• Cystic Fibrosis (CF) is associated with gastrointestinal dysfunction.
• Identifying reliable biomarkers for gut dysfunction in CF is crucial for patient management.
• Existing biomarkers require validation for repeatability and correlation with clinical outcomes.

Purpose of the Study:

• To evaluate biomarkers of gut dysfunction in pediatric cystic fibrosis (CF) patients.
• To assess the repeatability of these biomarkers over short intervals (2 weeks to 3 months).
• To determine if interindividual variations in biomarkers correlate with clinical outcomes in CF.

Main Methods:

• A cross-sectional, limited longitudinal study involving children with CF aged 1-21 years.
• Analysis of blood and stool samples for markers of intestinal inflammation (fecal calprotectin [fCal], lipocalin-2 [fLcn2], neopterin) and permeability.
• Enzyme immunoassays were used, with control specimens from children without CF.

Main Results:

• Fecal calprotectin (fCal), lipocalin-2 (fLcn2), and neopterin were significantly higher in CF patients compared to controls.
• fCal showed a negative correlation with changes in weight-for-age z-score, BMI z-score, and forced expiratory volume in 1 second (FEV1).
• fLcn2 was negatively correlated with FEV1, suggesting a link to pulmonary function decline.

Conclusions:

• Fecal lipocalin-2 (fLcn2) is elevated in individuals with CF and may serve as a predictor of worsening pulmonary function.
• Further studies are recommended to explore the correlation of fLcn2 with other clinical outcomes in CF.
• Intraindividual stability of LPS antibody was observed, but other markers showed variability.