In a 3-month-old infant with Down syndrome and signs of milk intolerance, what is the best next step when abnormal findings in health are present?

In the case of a 3-month-old infant with Down syndrome exhibiting signs of milk intolerance, ordering iron and total iron-binding capacity (TIBC) tests is the most appropriate next step to assess the infant's nutritional status and iron stores. Infants with Down syndrome are at increased risk for various health issues, including hematological conditions like iron-deficiency anemia. Given the signs of milk intolerance, it’s important to evaluate the infant’s iron levels, particularly if there is a history of feeding difficulties or changes in diet that could contribute to inadequate iron intake.

Performing these tests is crucial as they can identify potential anemia and allow for timely interventions to avoid complications associated with iron deficiency. The results can guide management strategies, including dietary adjustments and the possible need for iron supplementation.

While changing the diet to soy milk may seem like a reasonable step considering the milk intolerance, it should come after a full understanding of the infant’s nutritional status and possible iron deficiency, as soy milk can also be low in iron. Referral to a specialist might be warranted if there are severe or complex gastrointestinal symptoms, but for routine concerns regarding nutrition and possible intolerance, initial lab work is a prudent first step. Ordering a complete blood count is helpful but may not specifically address the immediate concern