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Pigmentary mosaicism (hypomelanosis of Ito)

Authors
Julie V Schaffer, MD
Karen A Chernoff, MD
Section Editors
Moise L Levy, MD
Jennifer L Hand, MD
Deputy Editor
Rosamaria Corona, MD, DSc

INTRODUCTION

The term "pigmentary mosaicism" refers to patterned hypo- or hyperpigmentation resulting from a clone of skin cells with altered ability to produce melanin. The three major clinical patterns are streaks and swirls following the Blaschko lines (figure 1), a segmental or "checkerboard" distribution, and a phylloid (leaf-like) arrangement.

This topic will discuss the epidemiology, pathogenesis, clinical manifestations, diagnosis, and treatment of pigmentary mosaicism. Other inherited and acquired disorders of pigmentation are discussed separately.

(See "Incontinentia pigmenti".)

(See "Acquired hyperpigmentation disorders".)

(See "Acquired hypopigmentation disorders other than vitiligo".)

                    
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Literature review current through: Sep 2017. | This topic last updated: Nov 29, 2016.
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