Introduction:
Allergy is immunological hypersensitivity. Allergic contact dermatitis (ACD) is formed on the reaction of cell hypersensitivity. Allergens, in allergic eczema, are haptene – incomplete allergens which, after proper skin penetration and connection to a protein carrier, become sterling. This is why the progression of allergic eczema is fundamental direct skin contact with haptene. The most common haptene in the dermatosis are metals, such as nickel, chromium or cobalt, rubber ingredients, flavourings and colourants.

Objective:
The aim of the study is to present the links between diseases from the group of allergic and autoimmunological diseases based on the analysis of the coexistence of allergic eczema and autoimmune thyroiditis in a single patient.

Material and Methods:
The material for analysis was diagnostic tests and a review of scientific reports in relation to the case of 40-year-old patient who presented with allergic skin eczema, and who was later diagnosed with autoimmune thyroid disease. As a part of the diagnostic test, the patient was examined with the European Baseline Series of patch tests. The purpose of the results and consultations was to establish the determinants of allergic contact dermatitis. The results obtained showed allergic eczema as an allergy to Phenylenediamine, Quaternium15, Rosin, and Budesonide; the patient was additionally diagnosed with autoimmune thyroid disease.

Conclusions:
This case shows that it is impossible to exclude a cross-correlation between these diseases. Based on the literature, it can be assumed that allergic contact dermatitis increases the predisposition of the occurrence of autoimmune thyroid disease. There is a need for further research in this area.