Analysis of exocrine pancreatic function in cystic fibrosis: one mild CFTR mutation does not exclude pancreatic insufficiency.
BACKGROUND
Cystic fibrosis (CF) is the most common cause of exocrine pancreatic insufficiency in childhood. The aim of the present study is to evaluate the correlation between genotype and exocrine pancreatic insufficiency in CF patients. The special emphasis was put on the analysis of mild CFTR mutations.


METHODS
The study comprised 394 CF patients and 105 healthy subjects (HS). Elastase-1 concentrations were measured in all subjects.


RESULTS
Severe pancreatic insufficiency was associated with the presence of two CFTR gene mutations (DeltaF508, N1303K, CFTR dele 2,3 (21kb), G542X, 1717-1G-A, R533X, W1282X, 621GT, 2183AAG, R560T, 2184insA and DeltaI507, G551D, 895T) and mild insufficiency with the presence of at least one mutation (R117H, 3171insC, A155P2, 138insL, 296 + 1G-A, E92GK, E217G, 2789 + 5G-A. 3849 + 1kbC-T/3849 + 1kbC-T) genotype resulted in high elastase-1-values. However, in case of patients with genotype DeltaF508/3849 + 10kbC-T, 1717-1GA/3849 + 10kbC-T as well as with DeltaF508/R334W, both high and low elastase-1 concentrations were found. Low E1 values were found in a patient with DeltaF508/R347P genotype.


CONCLUSIONS
Patients who carry two 'severe' mutations develop pancreatic insufficiency, whereas those who carry at least one 'mild' usually remain pancreatic sufficient. However, the presence of one mild mutation does not exclude pancreatic insufficiency.
Walkowiak
J
J
Karol Marcinkowski University of Medical Sciences, Poznan, Poland. jarwalk@sk5.usoms.poznan.pl
Herzig
K H
KH
Witt
M
M
Pogorzelski
A
A
Piotrowski
R
R
Barra
E
E
Sobczynska-Tomaszewska
A
A
Trawinska-Bartnicka
M
M
Strzykala
K
K
Cichy
W
W
Sands
D
D
Rutkiewicz
E
E
Krawczynski
M
M
D000328:Adult; D002648:Child; D002675:Child, Preschool; D003550:Cystic Fibrosis / Q000235:genetics* / Q000503:physiopathology*; D019005:Cystic Fibrosis Transmembrane Conductance Regulator / Q000235:genetics; D005223:Fats / Q000032:analysis; D005243:Feces / Q000201:enzymology; D005260:Female; D005838:Genotype; D006801:Humans; D007223:Infant; D008297:Male; D009154:Mutation; D010179:Pancreas / Q000502:physiology*; D010196:Pancreatic Elastase / Q000032:analysis; D010641:Phenotype
C505032:CFTR protein, human; D005223:Fats; D019005:Cystic Fibrosis Transmembrane Conductance Regulator; D010196:Pancreatic Elastase