Milk Protein Allergy

Abstract

Allergy is an immune system response to a foreign substance called allergens. Cow's milk contains more than 20 proteins which are allergens, that can cause allergic reactions. Allergy to milk proteins is one of the main food allergies and affects mostly but not exclusively infants, while it may also persist through adulthood and can be very severe. The incidence of milk protein allergy (MPA) can appear immediately or start several hours or even days after the intake of moderate to large amounts of milk or milk products or infant formula. MPA is different than other adverse reaction to milk, such as lactose intolerance, which is nonimmune mediated. Due to the type of immunologic responses to cow's milk proteins, MPA presents with a wide range of clinical syndromes as immunoglobulin E (IgE) mediated (immediate reaction) or non-IgE mediated (delayed reaction). Diagnosis of MPA can be achieved by skin or blood tests. Cow's Milk allergens are casein fractions and β-lactoglobulin (β-lg). Human and camel milks are free of β-lg. To reduce the allergenicity of cow milk proteins, heat or partial enzymatic treatments were done. Allergies to milk proteins of non-bovine mammals have also been documented. Goat or sheep milk, elicit the same reaction as cow's milk. Soy-based formula is not recommended for infant feeding due to similar allergic reactions. However, some recent clinical studies confirmed that camel milk in raw or fermented forms can be considered as a new protein source for nutrition of children allergic to cow milk. However, therapeutic benefits vary with the degree of severity of the allergy and may be only around 60% of all cases, since other studies revealed allergenicity to occur also for any of those other milks. No immunological similarity between camel and cow milk proteins was found. Some recent clinical studies confirmed that camel milk in raw or fermented forms can be considered as a new protein source for nutrition of children allergic to cow milk.