New method for the diagnosis of cystic fibrosis: dosage of chlorine and sodium in saliva by technique direct ion selective electrode

• Grant number: 14/06598-8
• Support Opportunities: Regular Research Grants
• Start date: August 01, 2014
• End date: October 31, 2016
• Field of knowledge: Health Sciences - Medicine - Pathological Anatomy and Clinical Pathology
• Principal Investigator: Carlos Emilio Levy
• Grantee: Carlos Emilio Levy
• Host Institution: Faculdade de Ciências Médicas (FCM). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Associated researchers: Antonio Fernando Ribeiro ; Elizete Aparecida Lomazi ; Ilma Aparecida Paschoal ; Jose Dirceu Ribeiro ; Regina Maria Holanda de Mendonca

Abstract

Cystic fibrosis (CF) is basically characterized by defective ion transport across the cell membrane in epithelial cells of the airways, pancreas, salivary glands, sweat, intestine and reproductive tract, resulting in mucosal secretions too thick and viscous, which cause obstruction at the level of glandular ducts and tubules. Certain systemic diseases, such as CF, may jeopardize the operation of the salivary glands and saliva production, thereby influencing both the amount of saliva produced and the quality of the fluid since it can affect the chemical components and physical properties of the. The reason for the great variability of the effects of CF on the salivary gland is unknown. Many of these studies were undertaken prior to determining the nature of the mutations that correlate with disease severity. The conclusive test for CF is the determination of sweat electrolytes, and this analysis has been used for over 50 years. Are currently accepted universal reference intervals for sweat chlorides, being applicable to all patients, regardless of gender or age. The Sweat Test, iontophoresis is performed by quantitative analysis of sweat ion stimulated by pilocarpine. Objectives: Validate the dosage of chlorine in saliva, the techniques of direct ion selective electrode (equipment blood gas analyser) and flame photometry / colorimetry and titrimetry for the diagnosis of cystic fibrosis. Patients and methods : A case control matched for age. Saliva samples of each individual will be analyzed by the technique of direct ion selective electrode (chloride and sodium), titrimetry (chlorine) and colorimetry for determination of chlorine and photometry to measure the sodium. The 02 sweat samples from each patient are analyzed by standard techniques of titration (chlorine) and flame photometry (sodium), and the techniques of colorimetry (chlorine) and direct ion selective electrode (chloride and sodium). The data will be processed and stored in the database created by the Statistical Package for Social Sciences ® (SPSS) for Windows version 17. The significance level of 5 % of the study will be submitted to descriptive analysis to obtain the absolute correlation of variables analyzed and frequencies. The Mann Whitney test will be used to evaluate the differences between the results of chloride and sodium in saliva (ion selective electrode, for chloride titration and flame photometry for sodium) obtained in patients with CF and individuals without cystic fibrosis, the same will be done with the results of the sweat (and colorimetric titration for chloride and flame photometry for sodium), with a significance level of 5 %. The ROC curve is applied to measure the sensitivity, specificity and determine the cut point (cut-off) of chlorine and sodium ions from saliva by the techniques of direct ion selective electrode, titration (chloride) and colorimetry (chlorine) and flame photometry (sodium). Expected results: check the efficiency of the analysis of chlorine and sodium in the saliva by the technique of direct ion selective electrode, and thus validate the method. (AU)