title: Role of CFTR mutation analysis in the diagnostic algorithm for cystic fibrosis.
abstract: BACKGROUND
  The cystic fibrosis transmembrane conductance regulator (CFTR) gene mutation identification is being used with increased frequency to aid in the diagnosis of cystic fibrosis (CF) in those suspected with CF. Aim of this study was to identify diagnostic outcomes when CFTR mutational analysis was used in CF diagnosis. CFTR mutational analysis results were also compared with sweat chloride results.
  
  
  METHODS
  This study was done on all patients at our institution who had CFTR mutation analysis over a sevenyear period since August 2006.
  
  
  RESULTS
  A total of 315 patients underwent CFTR mutational analysis. Fifty-one (16.2%) patients had two mutations identified. Among them 32 had positive sweat chloride levels (≥60 mmol/L), while seven had borderline sweat chloride levels (40-59 mmol/L). An additional 70 patients (22.3%) had only one mutation identified. Among them eight had positive sweat chloride levels, and 17 had borderline sweat chloride levels. Fifty-five patients (17.5%) without CFTR mutations had either borderline (n=45) or positive (n=10) sweat chloride results. Three patients with a CF phenotype had negative CFTR analysis but elevated sweat chloride levels. In eighty-three patients (26.4%) CFTR mutational analysis was done without corresponding sweat chloride testing.
  
  
  CONCLUSIONS
  Although CFTR mutation analysis has improved the diagnostic capability for CF, its use either as the first step or the only test to diagnose CFTR dysfunction should be discouraged and CF diagnostic guidelines need to be followed.
authors.affiliation: Department of Pediatrics, the Ohio State University College of Medicine, Columbus, Ohio, USA.|Section of Pulmonary Medicine, Department of Pediatrics, ED 444 Wolfe Education Building, Nationwide Children's Hospital, 700 Children's Drive, Columbus, OH, 43205, USA.
authors.forename: Michelle
authors.initials: M
authors.lastname: Ratkiewicz
authors.affiliation: Department of Pediatrics, the Ohio State University College of Medicine, Columbus, Ohio, USA.|Section of Human and Molecular Genetics, Nationwide Children's Hospital, Columbus, Ohio, USA.
authors.forename: Matthew
authors.initials: M
authors.lastname: Pastore
authors.affiliation: Department of Pediatrics, the Ohio State University College of Medicine, Columbus, Ohio, USA.|Section of Pulmonary Medicine, Department of Pediatrics, ED 444 Wolfe Education Building, Nationwide Children's Hospital, 700 Children's Drive, Columbus, OH, 43205, USA.
authors.forename: Karen Sharrock
authors.initials: KS
authors.lastname: McCoy
authors.affiliation: Department of Pediatrics, the Ohio State University College of Medicine, Columbus, Ohio, USA.|Section of Pulmonary Medicine, Department of Pediatrics, ED 444 Wolfe Education Building, Nationwide Children's Hospital, 700 Children's Drive, Columbus, OH, 43205, USA.
authors.forename: Rohan
authors.initials: R
authors.lastname: Thompson
authors.affiliation: Department of Pediatrics, the Ohio State University College of Medicine, Columbus, Ohio, USA.|Department of Internal Medicine, the Ohio State University College of Medicine, Columbus, Ohio, USA.|Section of Pulmonary Medicine, Department of Pediatrics, ED 444 Wolfe Education Building, Nationwide Children's Hospital, 700 Children's Drive, Columbus, OH, 43205, USA.
authors.forename: Don
authors.initials: D
authors.lastname: Hayes
authors.affiliation: Department of Pediatrics, the Ohio State University College of Medicine, Columbus, Ohio, USA. Shahid.Sheikh@nationwidechildrens.org.|Section of Pulmonary Medicine, Department of Pediatrics, ED 444 Wolfe Education Building, Nationwide Children's Hospital, 700 Children's Drive, Columbus, OH, 43205, USA. Shahid.Sheikh@nationwidechildrens.org.
authors.forename: Shahid Ijaz
authors.initials: SI
authors.lastname: Sheikh
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000465:Algorithms; D002648:Child; D002712:Chlorides / Q000032:analysis; D003550:Cystic Fibrosis / Q000235:genetics* / Q000503:physiopathology*; D019005:Cystic Fibrosis Transmembrane Conductance Regulator / Q000235:genetics*; D004252:DNA Mutational Analysis; D016208:Databases, Factual; D005260:Female; D005786:Gene Expression Regulation; D005820:Genetic Testing / Q000379:methods; D006801:Humans; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D013542:Sweat / Q000737:chemistry*; D055815:Young Adult
chemical_list: C505032:CFTR protein, human; D002712:Chlorides; D019005:Cystic Fibrosis Transmembrane Conductance Regulator
keywords: CFTR; cystic fibrosis; sweat chloride