Seborrhoeic eczema

Seborrhoeic eczema (syn. seborrhoeic dermatitis, morbus unna) is a common, chronic skin disease. Whether as an infant, adult or older person, almost everyone develops seborrhoeic eczema in his or her lifetime. In most cases, it is not very pronounced. However, up to 5% of the population suffer from a more pronounced form that requires treatment.
The disease typically starts with infants in the first three months of life and with adults as they approach forty.

Seborrhoeic eczema is a chronic inflammatory skin disease characterised by oily scaly, sharply defined, reddened and, in places itchy changes in the skin. These normally occur in areas rich in sebaceous glands such as the scalp, the forehead-hair lines, behind the ears, in the beard hair region, the hairy portion of the temples, eyebrows and the crease that runs from the nose down to the corners of the mouth. The middle of the chest, the armpits and groin are also more frequently affected. Those affected tend to have oily skin (seborrhoea).

Yeasts of the type pityrosporum probably play a role in the development of the disease. However, they are only one of a variety of possible factors.