Our findings agree with the new CF diagnosis guideline of lowering the intermediate cut-off values from 40–59 mmol/L to 30–59 mmol/L and performing genetic analysis to determine the presence of deleterious CFTR gene mutation to increase the probability of identifying individuals with CF and enable health providers to give appropriate therapy to help improve the quality of life of the affected individuals. This evidence concerns the gene CFTR and cystic fibrosis.