Very early onset perinatal constipation: Can it be cow’s milk protein allergy?

Table 3 Comparison of atypical vs typical cow’s milk protein allergy

	Atypical CMPA	Typical CMPA
Time of onset	Perinatal period[3]	Early infancy[21,22]
Way of transmission of allergen	Vertically via placenta and amniotic fluid[3]	Vertically via breast feeding
		Horizontally by oral ingestion[21,22]
Typical presentation	Intractable constipation[5,6]	Vomiting and diarrhea, bloody stools[21]
Type of allergy reaction	Non IgE mediated[5]	IgE mediated[5]
Tissues involved	Enteric neurons and smooth muscle[5-8]	Intestinal mucosa[5]
Mechanism involved	Immune mediated neuromuscular dysfunction leading to persistent spasm or failure to relax of the anorectum (HD like changes)[5-8]	Allergic enterocolitis[5]
Diagnosis	CMP avoidance and challenge. Both blood and skin allergy testings are of no diagnostic value[9]	CMP avoidance and challenge with or without blood and skin allergy testing[21]
Treatment	CMP avoidance[9]	CMP avoidance[9]
Awareness to providers	Rarely aware/reported	Well known/reported

CMP: cow’s milk protein; CMPA: cow’s milk protein allergy; HD: Hirschsprung’s disease; IgE: Immunoglobulin E.