Atopic dermatitis is a chronic inflammatory disease, usually associated with a personal or family history of atopic diseases such as AD, allergic rhinitis or asthma that most commonly arise in childhood and present with elevated IgE serum in up to 85% of patients. The severity of AD is based on the extent of affected areas, itch intensity and appearance of skin lesions. Here, we present the case of a 21-year-old female patient with generalized erythematous eczematous skin lesions, flexural lichenifications accompanied by intense pruritus, painful fissures and erosions resulting from scratching. She also presented erythematous plaques with thin scales on the scalp. The patient had no personal or familial history of AD, allergic rhinitis or asthma and the onset of cutaneous symptoms presented severe exacerbation in the last 2 months of the last 3 years. The main laboratory findings were- high serum eosinofilia (2400/microL) and very high total IgE serum (11449 UI/L). The flare remission was induced with systemic treatment (corticotherapy, oral H1 antihistamines, and antibiotherapy) and topical therapy (UVB 311 nm, topical glucocorticoids and hydration). It is very important to recognize AD as a cause of erythroderma, especially in a patient with a late onset of the disease, in order to treat it promptly and to prevent ulterior recurrences, by educating the patient to have an adequate life style and to treat the recurrences at the very first symptoms.