In a well-appearing neonate with painless bloody stools, what is the most likely diagnosis when combined with the presence of eczema?

In this scenario, the combination of painless bloody stools and the presence of eczema in a well-appearing neonate strongly suggests milk-protein induced enterocolitis. This condition typically involves an allergic reaction to proteins found in cow's milk or soy, leading to inflammation in the gastrointestinal tract.

The painless nature of the bloody stools aligns well with milk-protein induced enterocolitis, as it does not usually present with significant abdominal pain or distress. Furthermore, the association of eczema with this form of enterocolitis is crucial, as both conditions can arise from an underlying atopic diathesis, indicating a hypersensitivity or allergic response in the infant. Therefore, a diagnosis of milk-protein induced enterocolitis fits the clinical presentation described.

Other conditions, such as gastroenteritis, necrotizing enterocolitis, and infantile colic, do not typically present with the same symptom profile in this age group. Gastroenteritis usually causes vomiting and diarrhea that can be painful, while necrotizing enterocolitis is more common in preterm infants and is associated with significant distress and more severe abdominal symptoms. Infantile colic primarily manifests as excessive crying without a clear physical cause and does not typically present with bloody stools. Therefore,