Cow’s milk allergy (CMA) is one of the most common food allergies amongst infants and young children, affecting approximately 2-4% of this population worldwide. This article gives a brief overview including the epidemiology, patho-physiology, symptoms, diagnosis and management.

CMA, also known as cow’s milk protein allergy (CMPA), is an immune-mediated allergic response to one or more proteins in cow’s milk. It can be triggered in an infant by drinking cow’s milk or by drinking or eating products made from cow’s milk. This also includes the transition of milk protein from mum to baby when breastfeeding if mum has milk protein in her diet. Cow’s milk protein (CMP) can cause the immune system to be ‘sensitised’ so that when the protein is again consumed, the immune system remembers it and may react by producing allergic symptoms.

The Pathophysiology of CMA

The pathophysiology of CMA involves abnormal responses to proteins found in cow’s milk, particularly casein and whey proteins. There are several mechanisms involved, such as the immune system, genetic predisposition, gastrointestinal tract barrier dysfunction and microbiome and immune modulation.