Pigmentary mosaicism (hypomelanosis of Ito)
- Julie V Schaffer, MD
Julie V Schaffer, MD
- Attending in Pediatric Dermatology
- Director, Pediatric Dermatology Fellowship
- Division of Pediatric & Adolescent Dermatology
- Hackensack University Medical Center
- Karen A Chernoff, MD
Karen A Chernoff, MD
- Assistant Professor of Dermatology and Pediatrics
- Weill Cornell Medical College
- Section Editors
- Moise L Levy, MD
Moise L Levy, MD
- Section Editor — Pediatric Dermatology
- Professor of Pediatrics and Medicine (Dermatology)
- Dell Medical School, University of Texas, Austin
- Clinical Professor of Dermatology and Pediatrics
- Baylor College of Medicine
- Jennifer L Hand, MD
Jennifer L Hand, MD
- Section Editor — Genodermatoses
- Associate Professor of Dermatology, Medical Genetics, and Pediatrics
- Mayo Clinic, Rochester, MN
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".)
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- CLINICAL MANIFESTATIONS
- Linear nevoid hypo-/hyperpigmentation
- - Extracutaneous manifestations
- Segmental pigmentation disorder
- Phylloid hypomelanosis and hypermelanosis
- DIFFERENTIAL DIAGNOSIS
- Hypopigmentation along Blaschko's lines
- Hyperpigmentation along Blaschko's lines
- Hypo- or depigmentation in a block-like pattern
- Hyperpigmentation in a block-like pattern
- Pigmentary demarcation lines
- MANAGEMENT AND FOLLOW-UP
- SUMMARY AND RECOMMENDATIONS