system
Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
A 1-month-old boy is brought to the emergency department by his parents for recent episodes of non-bilious projectile vomiting and refusal to eat. The boy had no problem with passing meconium or eating at birth; he only started having these episodes at 3 weeks old. Further history reveals that the patient is a first born male and that the boy’s mother was treated with erythromycin for an infection late in the third trimester. Physical exam reveals a palpable mass in the epigastrum. Which of the following mechanisms is likely responsible for this patient’s disorder?
assistant
Hypertrophy of smooth muscle