Milk Protein Allergy (original) (raw)

Allergy means an altered or abnormal immunological reaction. The allergy may reach the tissues by direct contact with the skin or mucous membranes or through the blood stream after absorption. 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 allergy (MPA) widely varied from 0.3% to 7.5% in population-based symptoms of MPA can appear immediately or start several hours or even days after the intake of moderate to large amounts of milk or its products or infant formula. MPA can present with a spectrum of acute or delayed symptoms that can be mild to moderate or severe in nature. A wide spectrum of clinical manifestations has been recorded with MPA. Symptoms may affect the respiratory, cutaneous and gastrointestinal systems, or a combination of these systems. Therefore, diagnosis of MPA can be achieved by skin or blood tests. Milk contains more than 20 proteins (allergens), that can cause allergic reactions. The most common milk allergens are caseins and β-lactoglobulin (β-lg). Although, β-lg is a major whey protein fraction in milk of dairy animals, human and camel milks are free of β-lg. Several trials have been made to reduce the allergenicity of cow milk proteins as heat or partial enzymatic treatment. Allergies to milk proteins of non-bovine mammals have also been documented due to cross-reactivity between cow milk proteins and their counterpart in other species. Genetic polymorphisms of milk proteins play an important role in eliciting different degrees of allergic reactions. For example, goat milk lacking αs1-casein, which is the main casein in cow milk, is less allergenic than goat milk with αs2-casein, which is more typical for many goat breeds. Several studies have reported that goat or even soy milk can be used as alternatives in cases of cow milk allergy and they can be considered hypoallergenic. 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. Two recent clinical studies confirmed that camel milk can be considered as a new protein source for nutrition for children allergic to cow milk.