Clinical features associated with a delayed diagnosis of cystic fibrosis.
BACKGROUND
The majority of patients with cystic fibrosis (CF) are diagnosed in the first decade of life. In a small number of patients, the diagnosis is not made until later.


OBJECTIVE
In this study, the clinical and genetic features of patients diagnosed after the age of 10 were examined.


METHODS
All living patients in Northern Ireland diagnosed prior to 1983, when neonatal screening was introduced, were studied. A total of 103 patients were identified of whom 18 were diagnosed after the age of 10. The relationships between late diagnosis and clinical presentation, sputum microbiology, pancreatic sufficiency, nutritional status, genotype and distance from the regional CF centres was determined by multiple regression analysis.


RESULTS
All 18 late-diagnosed patients had a sweat (chloride >70 mmol/l). Late diagnosis was significantly related to carriage of the R117H mutation (r(2) = 0.45) and pancreatic sufficiency (r(2) = 0.37). There was a weak relationship with pulmonary function (r(2) = 0.09).


CONCLUSIONS
In Northern Ireland, late diagnosis in mainly associated with pancreatic function and carriage of the R117H mutation.
McCloskey
M
M
Paediatric Regional Cystic Fibrosis Centre, Belfast, Northern Ireland.
Redmond
A O
AO
Hill
A
A
Elborn
J S
JS
D000293:Adolescent; D000328:Adult; D016956:Burkholderia cepacia / Q000302:isolation & purification; D002712:Chlorides / Q000032:analysis; D003550:Cystic Fibrosis / Q000175:diagnosis* / Q000235:genetics / Q000382:microbiology / Q000503:physiopathology*; D019005:Cystic Fibrosis Transmembrane Conductance Regulator / Q000235:genetics; D005260:Female; D006801:Humans; D008168:Lung / Q000503:physiopathology; D008297:Male; D009154:Mutation; D010179:Pancreas / Q000503:physiopathology; D011549:Pseudomonas / Q000302:isolation & purification; D013183:Sputum / Q000382:microbiology; D013542:Sweat / Q000737:chemistry; D013997:Time Factors
C505032:CFTR protein, human; D002712:Chlorides; D019005:Cystic Fibrosis Transmembrane Conductance Regulator