As the UK's most common inherited life-threatening disease, CF affects internal organs and gives sufferers a life expectancy of about 31 years.
CF affects over 7,500 people in the UK and around one in 25 people carry the faulty gene which causes it. At present babies are routinely screened for the condition in Scotland, Wales and Northern Ireland, but this is not yet the case for all areas of England.
Just two-thirds of babies born in the UK are tested for CF.
In the latest study, researchers from the University of Dundee and University of East Anglia analysed data from the UK cystic fibrosis database for 2002.
They compared the treatment costs of 184 children aged one to nine who had been diagnosed with CF at newborn screening and 190 children in the same age group who were identified after clinical presentation of the disease.
The results showed that patients diagnosed by newborn screening cost significantly less to treat than those who were diagnosed clinically.
Patients in the latter group received therapy costing an estimated 60 to 400 per cent more than patients diagnosed by newborn screening.
"Newborn screening is associated with lower estimated treatment costs and reduced hospital admissions for invasive therapy, which suggests that indirect costs and disruption to family life will also be less," the researchers write.
"Furthermore, the potential cost savings to the yearly treatment budget could offset some, if not all, of the costs of a newborn screening service."
In an accompanying comment in the Lancet, Bridget Wilcken and Kevin Gaskin, both of the Children's hospital at Westmead, and University of Sydney, Australia, state: "If clear clinical benefit does not always persuade governments to implement screening, cost benefits might."
The Cystic Fibrosis Trust (CFT), which funds the UK CF database, has backed the calls for nationwide screening of the disease.
"We have campaigned for many years for all babies to be screened for CF at birth as part of the heel prick test. It is recognised that if babies are diagnosed and treated before they become symptomatic, they have a longer and better quality of life," said Alan Larsen, CFT's director of research.
"We hope that from mid-2007 all babies will be tested ensuring they have the same opportunities for early treatment."
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