Objective: In relatively few cases have perinatal factors been included as risk factors for allergy development. Delivery has not been considered as a possible influential factor in allergy development. To identify risk factors in allergy development, we have included erythema toxicum neonatorum (ETN).
Patients and methods: We have prospectively studied 356 newborns that were followed for a period of two years. Characteristics of the delivery, such as the pregnancy, instrumental delivery, circular cord, ETN, number of vesicles, day of presentation, season of birth, maternal and cord blood IgE levels and cord blood eosinophils and the development allergies during the two year follow-up period were included.
Results: ETN was seen in 25.3% of the children. The histopathology study of vesicles showed eosinophils. There was a significant difference between males and females (61.9% versus 38.1%, respectively). Cord blood IgE levels were not related to ETN, except in situations of allergy from 0.9 IU in cord blood or from 20 IU at six months of age (p < 0.05).
Conclusions: ETN is related to delivery characteristics, instrumental, circulars, amniotic alteration or fall in arterial pH < 7.24. In 84.2% of allergy manifestations during the first two years of life, ETN or a low pH was seen at birth, with atopic dermatitis being those that displayed ETN (85.7%).