A parent calls a clinic and reports to a nurse that his 2-month-old infant is hungry more than usual but is projectile vomiting immediately after eating. Which of the following responses should the nurse make?

Rationale: A. "Bring your baby in to the clinic today" is correct because projectile vomiting in a 2-month-old, especially when the infant remains hungry after vomiting, is a classic sign of hypertrophic pyloric stenosis. This condition causes narrowing of the pyloric sphincter, leading to obstruction of gastric emptying. Prompt in-person assessment is necessary to confirm the diagnosis and initiate treatment, which often involves surgical intervention (pyloromyotomy). Delaying evaluation could result in dehydration, electrolyte imbalances, and weight loss. B. "Give your infant an oral rehydration solution" is incorrect because while rehydration may be necessary if the infant is dehydrated, this is not the first action. The priority is diagnostic evaluation to determine the underlying cause of projectile vomiting, which may require urgent medical or surgical treatment. C. "Burp your baby more frequently during feedings" is incorrect because normal infant spitting up is usually small, effortless, and non-projectile. Burping will not correct the obstruction caused by hypertrophic pyloric stenosis, and this advice could delay proper treatment. D. "Try switching to a different formula" is incorrect because formula intolerance does not typically cause forceful, projectile vomiting immediately after every feeding in an otherwise healthy infant. Changing formula will not resolve the obstruction or prevent complications from pyloric stenosis.