Cardiac and respiratory disorders

Cystic fibrosis (CF) is the most common lethal autosomal
recessive disorder of childhood in Northern Europeans. The
incidence of cystic fibrosis is approximately 1 in 2000, with 1 in
22 people in the population being carriers. Clinical
manifestations are due to disruption of exocrine pancreatic
function (malabsorption), intestinal glands (meconium ileus),
bile ducts (biliary cirrhosis), bronchial glands (chronic
bronchopulmonary infection with emphysema), sweat glands
(abnormal sweat electrolytes), and gonadal function (infertility).
Clinical presentation is very variable and can include any
combination of the above features. Some cases present in the
neonatal period with meconium ileus, others may not be
diagnosed until middle age. Presentation in childhood is usually
with failure to thrive, malabsorption and recurrent pneumonia.
Approximately 15% of patients do not have pancreatic
insufficiency. Congenital bilateral absence of the vas deferens is
the usual cause of infertility in males with CF and can occur in
heterozygotes, associated with a particular mutation in intron 8
of the gene.