Sufferers are known as harlequin fetuses, harlequin babies, or harlequins.
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, mouth, and other appendages may be abnormally contracted. The scaly keratin greatly limits the child’s movement. Because the skin is cracked where normal skin would fold, it is easily pregnable by bacteria and other contaminants, resulting in serious risk of fatal infection.
Harlequin fetus is the most severe form of congenital ichthyosis with an incidence of one in 300.000 births. An autosomal recessive pattern of inheritance is seen in this disorder. However; a new autosomal dominant mutation may possibly be responsible. The disorder has an ominous prognosis since the neonates usually die in the first hours or days of life. We reported here; a case of harlequin fetus with a history of psoriasis in his father.
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.