From an article published by our group by Medeiros et al, we discuss and review the literature on the role of serum specific anti-ascaris IgE in patients with respiratory allergies living in countries where helminthic infestations are common. Medeiros et al conducted a study using 101 patients aged 12 to 21 years with respiratory allergy. Median IgE level was 660 IU/mL. Serum specific anti-ascaris IgE was positive in 73% (74/101) of the individuals, but parasitological stool examination yielded positive results in only 33.7% (34/101). The correlation coefficient between serum total IgE level and serum specific anti-ascaris IgE was 0.52 (P < 0.001) and this effect occurred regardless of eosinophil count and of the presence of intestinal helminthic infection. In patients with respiratory allergy with very high serum total IgE levels, in whom the past or present history of parasitic infection is a possible explanation, the presence of serum specific anti-ascaris IgE was common and should be better evaluated in allergic patients from Ascaris lumbricoides endemic areas.