Harlequin İchthyosis

Harlequin-type ichthyosis (also known as "Harlequin baby",[1] Harlequin ichthyosis,[1] ichthyosis congenita,[1] Ichthyosis fetalis, keratosis diffusa fetalis, "Harlequin fetus",[2]:562 and "Ichthyosis congenita gravior"[1]), a skin disease, is the most severe form of congenital ichthyosis, characterized by a thickening of the keratin layer in fetal human skin. In sufferers of the disease, the skin contains massive, diamond-shaped scales, and tends to have a reddish color. In addition, the eyes, ears, penis, and the appendages may be abnormally contracted. The scaly keratin greatly limits the child's movement. Because of resultant cracked skin in locations where normal skin would fold, it is easily pregnable by bacteria and other contaminants, resulting in serious risk of fatal infection.

The harlequin-type designation comes from both the baby's apparent facial expression and the diamond-shape of the scales (resembling the costume of Arlecchino), which are caused by severe hyperkeratosis. The disease can be diagnosed in the uterus by way of fetal skin biopsy or by morphologic analysis of amniotic fluid cells obtained by amniocentesis. In addition, doctors can now usually recognize common features of the disease through ultrasound, and follow up with 3D ultrasound to diagnose the condition.