Infants born with Harlequin-type Ichthyosis present with dry, scaly skin creating a diamond pattern on the body. Skin is much thicker than normal and does not bend so severe cracking occurs. When cracks forms, risk of infection increases. Some skin infections associated with Harlequin-type Ichthyosis can be fatal.

Craniofacial symptoms also occur with Harlequin-type Ichthyosis including undeveloped or missing ears, underdeveloped or missing nose, smaller than normal limbs, everted eyelids and stretched lips. At birth, bleeding of one or more areas is common as the skin has no natural lubrication and is stretched tight on the body.

Infants will suffer from a long list of side effects including sensitivity to room temperature changes, inability to grasp or hold and difficulty breathing. Infection is the most common cause of death in infants with Harlequin-type Ichthyosis.

When the condition was first diagnosed, prognosis was not good. Today, the longest living patient with Harlequin-type Ichthyosis is 26 years old and healthy.