Dermatological aspects of the S2k guidelines on Down syndrome in childhood and adolescence.

With an incidence of 1 in 700 births, Down syndrome (DS) is not an uncommon condition. It is associated with various disorders of different organ systems. Serious disorders include cardiac defects and leukemia. With an onset during the newborn period, the latter does not always progress to classic myeloid leukemia (transient myeloproliferative disorder). Skin manifestations in newborns include pustules/vesiculopustules. In individuals with DS, such lesions should not only prompt suspicion for typical neonatal rashes and infections but also for transient myeloproliferative disorder. However, most dermatoses are benign. They essentially comprise disorders of keratinization that present as xerosis, keratosis pilaris, lichenification, and ichthyosis vulgaris. Also typical but not specific is the four-finger palmar crease (simian crease). Patients frequently develop folliculitides, which - due to elastolysis - subsequently progress to anetoderma. The known immune disturbance in DS patients explains the occurrence of autoimmune diseases such as alopecia areata and vitiligo. Typical skin conditions associated with DS include elastosis perforans serpiginosa, syringomas, milia-like calcinosis cutis, and multiple eruptive dermatofibromas.