ABSTRACT
Cystic fibrosis (CF) is the most common serious inherited defect affecting the Caucasian population. Cystic fibrosis is transmitted as an autosomal recessive condition with a 5 percent carrier rate and an incidence of approximately 1:2500 live births. The cystic fibrosis transmembrane conductance regulator (CFTR) gene is located on the long arm of chromosome 7. According to the Cystic Fibrosis Genetic Analysis Consortium, 13 mutations occur at a frequency of greater than 1 percent and account for 87 percent of CF alleles. The delta F508 mutation is the most common and is present in 70 percent of CF alleles in the United States. There are great differences among
populations, and among African Americans delta F508 only accounts for 43 percent of the alleles. The CFTR protein controls sodium and chloride transport and in cystic fibrosis this results in abnormal luminal secretions. Neonatal intestinal obstruction due to inspissated meconium has been identified since the early reports concerning cystic fibrosis and is referred to as meconium ileus. This presentation is observed in 10-15 percent of infants born with cystic fibrosis. The etiology of this abnormal meconium (mucoviscidosis) is due to deficient pancreatic and intestinal secretions, as well as an abnormal concentration of the meconium within the duodenum and proximal jejunum. Instances of meconium ileus can be classified into uncomplicated and complicated cases.
