Harlequin Fetus

Abstract

Harlequin fetus is the most severe type of ichthyosis known. The American Rev. O. Hart is generally credited [9] with the first description of this devastating disease in the year 1750. The first medical report seems to be a dissertation by Richter in 1792 [11]. In 1900, Erhard Riecke [12] performed the first histologic study of a harlequin fetus which had been conserved in alcohol solution for more than 30 years at the University of Leipzig. In his classical paper entitled “Über Ichthyosis congenitaȝ (On ichthyosis congenita) he reviewed the available literature from the nineteenth century and concluded that harlequin fetus (ichthyosis congenita type 1, according to Riecke) should be distinguished from what is today known as lamellar ichthyosis. Of the 54 case reports he reviewed, Riecke considered 25 cases to be harlequin fetus, whereas the remainder suffered from a less severe disease and were classified as ichthyosis congenita types 2 and 3. Riecke noted parental consanguinity in several instances, occurrence of the disease in siblings, and involvement of both sexes. In his detailed histologic description he emphasized the marked increase of the stratum corneum and prominent keratinization of hair follicles, contrasting with a normally developed Malpighian and granular layer.