Poor growth in an infant with cystic fibrosis due to an antenatal perforation and incomplete bowel obstruction

The infant was born at term weighing 2860 g, the first child of healthy unrelated parents. Routine antenatal scans had been normal. Delivery was via a breech presentation and clinical signs of congenital dysplastic hips (CDH) were detected on newborn examination and a referral wasmade to an orthopaedic surgeon. He passed meconium within the first 24 h and was discharged on the second day of life. At 16 days of age he was readmitted with a short history of loose stools and poor feeding. He had lost 22% of his birth weight. He was hyponatraemic with a conjugated hyperbilirubinaemia and an elevated c-reactive protein. He was treated for presumed sepsis. A week later cystic fibrosis (CF) was suggested on newborn screening results (homozygous p.Phe508del). Treatment was