Don't Forget Your Basics: A Late Diagnosis of Cystic Fibrosis in a Child.

Delayed diagnosis of Cystic Fibrosis (CF) can occur. We present a 5-year African American boy with respiratory issues, fevers, rectal prolapse, oily stools, and failure to thrive; despite normal newborn screening. He had low weight (5th percentile), speech delay, maculopapular rash, and finger clubbing. Laboratories showed elevated amylase, low vitamin D, high fecal calprotectin, sweat chloride of 92 and 96 mmol/L, and DeltaF508/DeltaF508 mutations. After initiating pancreatic enzyme therapy, his nutrition improved with respiratory symptom relief. This case highlights the need for suspicion of CF in patients with recurrent respiratory and gastrointestinal symptoms, even with a normal newborn screening.