Severe asthma and anaphylaxis in a cow's milk-allergic patient.: Sheep's, goat's or horse's milk as an alternative for milk-protein-allergic persons

A 24-year-old man was suffering from severe asthma, urticaria and generalized pruritus since the age of 14 after eating all kinds of cow's milk products. Even the ingestion of small amounts of cheese and butter produced the same symptoms. Serologic testing showed a sensitization to casein (CAP class 5, 68.2 kU/L). Prick testing showed a strongly positive reaction to cow's milk and cheese. Prick-to-prick testing with feta cheese was negative so an oral challenge test with feta cheese was done, started with 5 g. 15 minutes after ingestion he presented a conjunctivitis and a running nose, followed by edema and a severe asthma attack. The following examination showed highly elevated specific IgE to casein, especially to the fraction of alpha(1)-casein to cow's, sheep's and goat's milk. The patient was told to follow a milk-free diet. In case of an accidental ingestion of milk the patient was given emergency medicaments (antihistamines, steroids and adrenaline for subcutaneous injection). Cross reactions can explain allergic reactions to other milk species, so goat's, sheep's and horse's milk is definitely no generalized alternative. In any case testing and if uncertainties remain, double blind oral food challenge is necessary.