Increased Plasma YKL-40 Level and Chitotriosidase Activity in Cystic Fibrosis Patients

Abstract Background We investigated plasma YKL-40 levels and chitotriosidase (CHIT1) activity in patients with cystic fibrosis (CF) lung disease and evaluated clinically relevant factors that may affect their levels. Methods Plasma samples were obtained from pediatric (n = 19) and adult patients (n = 15) during exacerbation, discharge and stable period of the disease. YKL-40 levels and chitotriosidase activity were measured by enzyme-linked immunosorbent assay and fluorometric assay, respectively. Data were compared with healthy children and adults of similar age. Results YKL-40 levels of pediatric and adult CF patients at all periods were significantly higher than controls (p < 0.001 and p < 0.05). CHIT1 activities of adult patients at all periods were significantly higher compared to controls (p < 0.05). On the other hand, CHIT1 activities of pediatric CF patients were similar with controls. YKL-40 levels of exacerbation period of adult CF patients were negatively correlated with % FVC (r= -0.800, p = 0.014) and % FEV1 (r= -0.735, p = 0.008). YKL-40 levels in the exacerbation period of pediatric CF patients were negatively correlated with % FVC (r= -0.697, p = 0.0082) and % FEV1 (r= -0.720, p = 0.006). Conclusions CHIT1 activity may be a valuable marker of chronic inflammation in adult CF patients who suffer from CF for a longer period of time compared to pediatric patients. Increased YKL-40 levels in both pediatric and adult patients compared to controls may point to a role in between CF pathology. Furthermore, as YKL-40 levels are correlated with FEV1 and FVC in patients, it may be useful for the monitoring of pulmonary function in CF patient.