IGHE and mastocytosis: Interestingly, in our study, the patient with a low alpha-gal IgE level (2.96 kU/L) presented recurrent idiopathic anaphylaxis; in the patient with diagnosed mastocytosis, the alpha-gal IgE level was positive, although as low as 0.75 kU/L; at the same time, in the patient with isolated angioedema, the alpha-gal IgE level was 100 kU/L [10].