Most common lethal autosomal recessive inherited disorder in Caucasian population
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CFTR mutation on chromosome 7
Abnormal chloride transport in apical membrane of epithelial cells
Clinical Issues
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1 in 2,000-2,500 live births
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Respiratory complaints are common presentation
Patients rarely present initially with liver disease
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Up to 40% of affected adolescents have evidence of liver disease
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Cirrhosis accounts for virtually all nonpulmonary deaths in cystic fibrosis (CF)
As life expectancy increases, hepatobiliary disease in CF more often recognized
Microscopic
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Focal biliary fibrosis is characteristic lesion
Dilated, proliferated bile ductules
Dense secretions/concretions represent abnormal secretions of CF
PAS positive (diastase resistant); mucicarmine and Alcian blue negative
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Fibrous, expanded portal tracts with variable inflammation
Disease may progress to multilobular biliary cirrhosis
Top Differential Diagnoses
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Primary sclerosing cholangitis (PSC)
PSC and CF may mimic each other on ERCP
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Neonatal hepatitis of other causes
TERMINOLOGY
Abbreviations