The cystic fibrosis transmembrane conductance regulator gene and ion channel function in patients with idiopathic pancreatitis.
Cystic fibrosis transmembrane conductance regulator (CFTR) gene mutations are associated with cystic fibrosis (CF)-related monosymptomatic conditions, including idiopathic pancreatitis. We evaluated prospectively enrolled patients who had idiopathic recurrent acute pancreatitis or idiopathic chronic pancreatitis, healthy controls, CF heterozygotes, and CF patients (pancreatic insufficient or sufficient) for evidence of CFTR gene mutations and abnormalities of ion transport by sweat chloride and nasal potential difference testing. DNA samples from anonymous blood donors were controls for genotyping. At least one CFTR mutation or variant was carried in 18 of 40 patients (45%) with idiopathic chronic pancreatitis and in 6 of 16 patients (38%) with idiopathic recurrent acute pancreatitis but in only 11 of the 50 controls (22%, P=0.005). Most identified mutations were rare and would not be identified in routine genetic screening. CFTR mutations were identified on both alleles in six patient (11%). Ion transport measurements in patients with pancreatitis showed a wide range of results, from the values in patients with classically diagnosed CF to those in the obligate heterozygotes and healthy controls. In general, ion channel measurements correlated with the number and severity of CFTR mutations. Twelve of 56 patients with pancreatitis (21%) fulfilled current clinical criteria for the diagnosis of CF, but CFTR genotyping alone confirmed the diagnosis in only two of these patients. We concluded that extensive genotyping and ion channel testing are useful to confirm or exclude the diagnosis of CF in the majority of patients with idiopathic pancreatitis.
Bishop
Michele D
MD
Department of Medicine, Beth Israel Deaconess Medical Center, Harvard School of Medicine, Boston, MA, USA.
Freedman
Steven D
SD
Zielenski
Julian
J
Ahmed
Najma
N
Dupuis
Annie
A
Martin
Sheelagh
S
Ellis
Lynda
L
Shea
Julie
J
Hopper
Isobel
I
Corey
Mary
M
Kortan
Paul
P
Haber
Gregory
G
Ross
Christine
C
Tzountzouris
John
J
Steele
Leslie
L
Ray
Peter N
PN
Tsui
Lap-Chee
LC
Durie
Peter R
PR
D000328:Adult; D016022:Case-Control Studies; D002908:Chronic Disease; D003550:Cystic Fibrosis / Q000150:complications / Q000175:diagnosis* / Q000235:genetics*; D019005:Cystic Fibrosis Transmembrane Conductance Regulator / Q000235:genetics* / Q000502:physiology*; D004252:DNA Mutational Analysis; D005260:Female; D005838:Genotype; D006801:Humans; D007473:Ion Channels / Q000235:genetics* / Q000502:physiology*; D008297:Male; D010195:Pancreatitis / Q000209:etiology / Q000235:genetics* / Q000473:pathology; D011446:Prospective Studies
D007473:Ion Channels; D019005:Cystic Fibrosis Transmembrane Conductance Regulator