Question: 5-week-old boy presents to his pediatrician’s office with a 10-day history of diaper rash and difficulty feeding. His parents describe the rash as red, firm, and spreading despite consistent use of barrier creams and antibiotic ointment. The rash involved only the buttocks at onset, but it has spread to the thighs and lower back. He is exclusively breastfed

5-week-old boy presents to his pediatrician’s office with a 10-day history of diaper rash and difficulty feeding. His parents describe the rash as red, firm, and spreading despite consistent use of barrier creams and antibiotic ointment. The rash involved only the buttocks at onset, but it has spread to the thighs and lower back. He is exclusively breastfed and often falls asleep at the breast or begins to arch his back, grimace, and pull away mid- feed. Trials with ranitidine and formula supplementation after breastfeeding have been attempted without improvement. He continues to void and stool appropriately. There is no history of fever, excessive spitting up, increased work of breathing or diaphoresis with feeds, or other systemic symptoms. His perinatal history is significant for term gestation and terminal meconium without aspiration. Apgar scores were 2 at 1 minute and 8 at 5 minutes. He was admitted to the special care….