title: Assessing the improvements in the newborn screening strategy for cystic fibrosis in the Balearic Islands.
abstract: OBJECTIVE
  Newborn screening strategies for cystic fibrosis (CF) are run worldwide, and aim at the early detection of the disorder to significantly improve the quality of life. Elevated levels of immunoreactive trypsinogen (IRT) represent a high likelihood for the screened child to be affected with CF. However, the specificity of IRT is low. The objective of this study was to assess the screening program in the Balearic Islands during the past 14 years.
  
  
  METHODS
  We evaluated all results of the screening program after 14 years, by considering all changes in the protocol and assessing the number of positive samples, the mutations detected, the number of sweat tests performed, the incidence of CF and the presence of false-negative cases.
  
  
  RESULTS
  Despite a great variability among the different Balearic Islands, the global incidence of CF was 1:6059 for the 14 years assessed. The incidence in the smaller islands is about 5 times higher than in Majorca (1:2376 versus 1:10,613). After different changes in the protocol, an IRT cut-off value of 60 ng/mL was established. The two most common mutations are ΔF508 and G542X, in accordance with other geographical regions.
  
  
  CONCLUSIONS
  The changes in the protocol helped reduce the number of sweat tests performed without any increase in the false-negative rate.
authors: Servei d'Anàlisis Clíniques, Hospital Universitari Son Espases, Palma de Mallorca, Spain. Electronic address: pepmiquel@gmail.com.
authors: Josep Miquel
authors: JM
authors: Bauça
authors: Servei d'Anàlisis Clíniques, Hospital Universitari Son Espases, Palma de Mallorca, Spain.
authors: Daniel
authors: D
authors: Morell-Garcia
authors: Servei d'Anàlisis Clíniques, Hospital Universitari Son Espases, Palma de Mallorca, Spain.
authors: Magdalena
authors: M
authors: Vila
authors: Servei d'Anàlisis Clíniques, Hospital Universitari Son Espases, Palma de Mallorca, Spain.
authors: Gerardo
authors: G
authors: Pérez
authors: Servei de Genètica, Hospital Universitari Son Espases, Palma de Mallorca, Spain.
authors: Damián
authors: D
authors: Heine-Suñer
authors: Servei de Pediatria, Hospital Universitari Son Espases, Palma de Mallorca, Spain.
authors: Joan
authors: J
authors: Figuerola
mesh_terms: D003550:Cystic Fibrosis / Q000175:diagnosis* / Q000235:genetics / Q000276:immunology; D019005:Cystic Fibrosis Transmembrane Conductance Regulator / Q000235:genetics; D004252:DNA Mutational Analysis; D006801:Humans; D007231:Infant, Newborn; D025202:Molecular Diagnostic Techniques; D020125:Mutation, Missense; D015997:Neonatal Screening / Q000592:standards*; D017063:Outcome Assessment, Health Care; D058996:Quality Improvement; D013030:Spain; D014362:Trypsinogen / Q000276:immunology
chemical_list: C505032:CFTR protein, human; D019005:Cystic Fibrosis Transmembrane Conductance Regulator; D014362:Trypsinogen
keywords: False-positive rate; Newborn screening; Strategy; Sweat test