Neurodermatitis (Atopic Eczema): Causes

Pathogenesis (disease development)

In patients with atopic eczema (neurodermatitis), there is a disturbance in the immune response. T helper cells belong to the lymphocytes (defense cells) and are carriers of specific defense.

In healthy individuals, there is a balance between the subsets of T-helper cells, whereas in atopic dermatitis patients with the intrinsic form, TH2 cells outnumber TH1 cells. These TH2 cells produce interleukins (messengers) that lead to the release of antibodies and histamine, which causes allergic reactions. TH1 cells are more likely to produce substances that prevent allergic reactions.

Similarly, extrinsic-type atopic dermatitis patients have increased secretion of IgE (immunoglobulin E), which indicates contact with type I aeroallergens (pollen, mites, molds) or type I food allergens (up to 30% of cases in infancy and early childhood). Furthermore, type IV contact allergens and skin irritants are among the provoking factors of atopic eczema.

It should be noted, however, that not all atopic dermatitis is IgE-mediated.

Furthermore, neurodermatitis is characterized by a skin barrier disorder, caused by a genetic disposition, and a nervous interaction (psychosomatic influence). In this context, the skin barrier disorders occur at a very early age, even before clinical symptoms develop.

Etiology (causes)

Biographic causes

  • Genetic burden from parents, grandparents; 80% concordance in monozygotic (identical) vs 20% in dizygotic (fraternal) twins
    • Genetic risk dependent on gene polymorphisms:
      • Genes/SNPs (single nucleotide polymorphism):
        • SNP: rs7927894 in an intergenic region.
          • Allele constellation: TT (1.2-fold).
          • Allele constellation: CC (0.83-fold)
  • Mother:
    • Higher maternal intake of free sugars during pregnancy may increase the risk of atopy and atopic asthma in offspring.
    • Postpartum depression: adjusted odds ratio [aOR] for the risk of developing atopic dermatitis was 1.32; at five and nine years of age, there was a significant relationship (aOR: 1.34 and 1.37, respectively); severe postpartum depression further increased the risk (aOR: 1.58 and 1.73, respectively); late maternal depression was also significantly associated with the risk of developing atopic dermatitis.

Behavioral causes

  • Nutrition
    • Abstinence from breastfeeding infants (protective (protective) effect of breast milk feeding; breastfeeding for at least >4 months).
    • Giving complementary food before completion of the fifth month of life in infants.
    • Micronutrient deficiency (vital substances) – see prevention with micronutrients.
  • Consumption of stimulants
  • Psycho-social situation
    • Stress
  • Daily bathing of the children
  • Omitting the daily airing of the apartment
  • Use of materials made from animal products such as mattresses with feathers.

Causes related to disease

  • Infections
  • Airborne allergens or bacteria
  • Food allergy

Environmental pollution – intoxications

  • Damp walls (molds; during the first year of life).

Trigger factors – see this under the sub-topic “Prevention”.