Meconium ileus in a newborn is often associated with which congenital condition?

• A. Turner syndrome.
• B. Tay-Sachs disease.
• C. Cystic fibrosis.
• D. Marfan syndrome.

Answer: (C)

Meconium ileus happens when thick, sticky meconium blocks the ileum in a newborn. This thick mucus is a hallmark of cystic fibrosis, where the CFTR gene defect leads to dehydrated, viscous secretions throughout the body, including the gastrointestinal tract. In newborns with CF, the meconium can plug the distal intestine, causing obstruction that is often one of the first clues leading to a CF diagnosis. Because of this strong, well-known association, cystic fibrosis is the best answer.

The other conditions listed don’t typically present with meconium ileus. Turner syndrome is a chromosomal disorder with features like short stature and gonadal dysgenesis; Marfan syndrome is a connective-tissue disorder with cardiovascular and skeletal findings; Tay-Sachs disease is a neurodegenerative disorder. None of these characteristically cause the thick, obstructive meconium seen in meconium ileus.