Serum and nasal lavage fluid Clara cell protein decreases in children with allergic rhinitis

Allergic rhinitis is among the most common chronic disorders of childhood with prevalence of up to 40% in children. Clara cell secretory protein (CCSP) is secreted by Clara cells in the lining fluid of airways. It has an immune-modulatory and anti-inflammatory activity.

Study aimed at evaluating CCSP as a biomarker in serum and nasal lavage fluid of children with allergic rhinitis.

A case-control study was conducted on sera and nasal lavage fluid samples from 15 children with allergic rhinitis and 15 healthy children as a control group.

Children with allergic rhinitis had a male to female ratio 2 to 1, with a mean age of 9.47±2.75 years, while among the healthy group, six were males and nine were females, with a mean age of 8.63±2.28 years. Rhinorrhea and nasal obstruction were the most frequent symptoms (100%) followed by itching (93.3%) then sneezing (73.3%). Among allergic rhinitis patients serum CCSP mean±SD was 2.03±0.59μg/l; it was reliable to predict allergic rhinitis (P<0.0001); while nasal lavage CCSP mean±SD was 12.73±8.25μg/l and it was not reliable to predict allergic rhinitis. Its best cut-off value was 3.75μg/l with a sensitivity of 100%, specificity 80%, with a diagnostic accuracy of 90%.

Clara cell secretory protein is a new peripheral sensitive marker of airway injury. Furthermore, serum CCSP level is a predictor of allergic rhinitis but not nasal lavage fluid CCSP.