Features of clorine ions concentration in suspected cystic fibrosis patients sweat test and its correlation with C reactive protein

Backround: It is essential to confirm or exclude the diagnosis of cystic fibrosis in time and with accuracy in order to avoid inappropriate testing. The aims of this study was to determine features of Cl ions concentration in patients sweat test that were suspected having cystic fibrosis and to evaluate correlation between this concentration and C reactive protein levels in serum. Methods: we investigated retrospectively case files of patients with performed sweat test in period of 2011-2012 in Hospital of Lithuanian University of Health Sciences Kauno Klinikos Paediatrics department. These patients were suspected having cystic fibrosis (n=48). Results: 9 out of 48 patients (18,75 % ) showed higher than normal Cl ions concentration values. 6 of them (12,5%) had a borderline concentration. Mean value of Cl ions concentration in males sweat was 25,37 mmol/l (p<0,05; PI=21,05-30,40) and there was no statistical significance compared to mean Cl ions concetration in females sweat which was 24,44 mmol/l (p<0,05; PI=19,96-28,91). In our study no mutations of CFTR gene were found. CRP test was performed in 17 cases (35,42%). No statisticly significant correlation between concentration of Cl ions in sweat and serum CRP was found (r= -0,16; p=0,531 ). Conclusions: 18,75% of checked patients had a higher than normal Cl ions concetration in sweat test. No statisticly significant difference between Cl ions concentrations in sweat test according to gender was found in examined group.