What is a harlequin fetus?

The most severe manifestation of congenital ichthyosis, the harlequin fetus, is born with massive hyperkeratotic plates associated with limb deformities, rudimentary ears, ectropion, and eclabium. These infants rarely survive beyond the first week of life. The use of acitretin in harlequin ichthyosis may be lifesaving, although side effects are numerous and may be severe.