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A QUICK REFERENCE GUIDE

American Academy of Pediatrics
Section on Dermatology
Editors: Daniel P. Krowchuk, MD, FAAP,
and Anthony J. Mancini, MD, FAAP
Now you can consult a single authoritative AAP resource for the guidance
you need to evaluate, diagnose, treat, and manage more than 100 pediatric
and adolescent skin conditions.
More than 250 full-color images aid in accurate recognition and
differential diagnosis.
Bullous Diseases
Genodermatoses
Hair Disorders
Skin Disorders in Neonates/Infants
Drug Eruptions
Cutaneous Manifestations of
Rheumatologic Diseases
Other Disorders

Daniel P. Krowchuk, MD, FAAP
Anthony J. Mancini, MD, FAAP

Selected content highlights
Dermatitis
Acne
Skin Infections
Infestations
Papulosquamous Diseases
Vascular Reactions
Vascular Lesions
Disorders of Pigmentation
Lumps and Bumps

Pediatric Dermatology

P
Dermatology
y
Pediatric
Dermatology

Custom-built for efficient, confident problem-solving
Essential information on each condition is presented in the precise sequence
in which you need it in the clinical setting.
•
•
•
•

Etiology/Epidemiology
Signs and Symptoms
Look-alikes

How to Make the Diagnosis

•
•
•
•

Treatment
Prognosis
When to Worry or Refer
Resources for Families

For other pediatric resources,
visit the American Academy of
Pediatrics online Bookstore at
www.aap.org/bookstore.

AAP

Pediatric
Dermatology
A QUICK REFERENCE GUIDE
Editors
Daniel P. Krowchuk, MD, FAAP
Anthony J. Mancini, MD, FAAP


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Pediatric Dermatology
A Quick Reference Guide

Section on Dermatology
American Academy of Pediatrics
Editors
Daniel P. Krowchuk, MD, FAAP
Anthony J. Mancini, MD, FAAP


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Page ii

American Academy of Pediatrics Department of Marketing and
Publications Staff
Maureen DeRosa, MPA
Director, Department of Marketing and Publications
Mark Grimes
Director, Division of Product Development
Jeff Mahony

Manager, Product Development
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Library of Congress Control Number: 2006928514
ISBN-10: 1-58110-220-8
ISBN-13: 978-1-58110-220-8
MA0354
The recommendations in this publication do not indicate an exclusive course of treatment or
serve as a standard of medical care. Variations, taking into account individual circumstances,
may be appropriate.
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imply endorsement by the American Academy of Pediatrics.
Copyright © 2007 American Academy of Pediatrics. All rights reserved. No part of this
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or by any means, electronic, mechanical, photocopying, recording, or otherwise, without
prior permission from the publisher. Printed in China.
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Reviewers/Contributors
Editors
Daniel P. Krowchuk, MD, FAAP
Chief, General Pediatrics and Adolescent Medicine
Department of Pediatrics
Wake Forest University School of Medicine
Winston-Salem, NC
Anthony J. Mancini, MD, FAAP, FAAD
Associate Professor of Pediatrics and Dermatology
Northwestern University Feinberg School of Medicine
Head, Division of Pediatric Dermatology
Children’s Memorial Hospital
Chicago, IL
Associate Editors
J. Thomas Badgett, MD, PhD, FAAP
Professor of Pediatrics
University of Louisville School of Medicine
Louisville, KY
Amy J. Nopper, MD, FAAP, FAAD
Associate Professor of Pediatrics/Dermatology

University of Missouri–Kansas City School of Medicine
Section Chief, Dermatology
Children’s Mercy Hospitals & Clinics
Kansas City, MO
Steven D. Resnick, MD, FAAP, FAAD
Chief, Division of Dermatology
Bassett Healthcare
Associate Clinical Professor of Dermatology
College of Physicians and Surgeons, Columbia University
Cooperstown, NY
Michael L. Smith, MD, FAAP, FAAD
Associate Professor of Medicine and Pediatrics
Division of Dermatology
Vanderbilt University Medical Center
Nashville, TN


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Reviewers/Contributors

Patricia A. Treadwell, MD, FAAP, FAAD

Assistant Dean for Cultural Diversity
Professor of Pediatrics
Indiana University School of Medicine
Riley Children’s Hospital
Indianapolis, IN
American Academy of Pediatrics Board of Directors Reviewer
Kathryn Piziali Nichol, MD, FAAP
American Academy of Pediatrics
Errol R. Alden, MD, FAAP
Executive Director/CEO
Roger F. Suchyta, MD, FAAP
Associate Executive Director
Maureen DeRosa, MPA
Director, Department of Marketing and Publications
Mark Grimes
Director, Division of Product Development
Jeff Mahony
Manager, Product Development
Lynn Colegrove, MBA
Manager, Section on Dermatology
Mark Ruthman
Electronic Product Development Editor
Reviewers
Committee on Drugs
Committee on Environmental Health
Committee on Genetics
Council on School Health
Section on Clinical Pharmacology & Therapeutics
Section on Infectious Diseases
Section on Plastic Surgery

Section on Rheumatology
Copy Editor
Kate Larson
Cover Design by DesignWorld
Book Design by Linda J. Diamond


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Dedication
Dedicated to our families—Heidi and Will; Nicola, Mallory, Christopher, and
MacKenzie—whose understanding and support made this project possible.


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Table of Contents

vii

Table of Contents
Foreword ....................................................................................................................xi
Editors’ Note ............................................................................................................xii
1
2
3

Approach to the Patient With a Rash ..................................................................1
Diagnostic Techniques ..........................................................................................7
Therapeutics ........................................................................................................13

Dermatitis
4 Atopic Dermatitis ................................................................................................21
5 Contact Dermatitis (Irritant and Allergic)........................................................31
Acne
6 Acne Vulgaris ......................................................................................................41
7 Neonatal and Infantile Acne ..............................................................................53
8 Periorificial Dermatitis ......................................................................................57
Skin Infections

Localized Viral Infections
9 Herpes Simplex....................................................................................................63
10 Herpes Zoster ......................................................................................................71
11 Molluscum Contagiosum ..................................................................................75
12 Warts ....................................................................................................................79
Systemic Viral Infections
13 Erythema Infectiosum/Human Parvovirus B19 Infection (Fifth Disease) ........87
14 Gianotti-Crosti Syndrome ..................................................................................91
15 Hand-Foot-and-Mouth Disease (HFMD)/Herpangina ..................................95
16 Measles ................................................................................................................99
17 Papular-Purpuric Gloves and Socks Syndrome (PPGSS) ..............................105
18 Roseola Infantum (Exanthem Subitum) ........................................................109
19 Rubella ..............................................................................................................111
20 Unilateral Laterothoracic Exanthem (ULE)....................................................117
21 Varicella..............................................................................................................119
Localized Bacterial Infections
22 Acute Paronychia ..............................................................................................125
23 Blistering Dactylitis ..........................................................................................129
24 Ecthyma ............................................................................................................131


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Table of Contents

25 Folliculitis/Furunculosis/Carbunculosis..........................................................135
26 Impetigo ............................................................................................................139
27 Perianal Streptococcal Dermatitis....................................................................143
Systemic Bacterial, Rickettsial, or Spirochetal Infections With Skin
Manifestations
28 Lyme Disease ....................................................................................................149
29 Meningococcemia ............................................................................................153
30 Rocky Mountain Spotted Fever (RMSF) ........................................................157
31 Scarlet Fever ......................................................................................................161
32 Staphylococcal Scalded Skin Syndrome (SSSS) ..............................................165
33 Toxic Shock Syndrome (TSS) ..........................................................................169
Fungal and Yeast Infections
34 Candida..............................................................................................................175
34A Angular Cheilitis/Perlèche........................................................................177
34B Candidal Diaper Dermatitis ....................................................................179
34C Chronic Paronychia ..................................................................................181
34D Neonatal/Congenital Candidiasis ............................................................183
34E Thrush ......................................................................................................187
35 Onychomycosis..................................................................................................189
36 Tinea Capitis......................................................................................................193
37 Tinea Corporis ..................................................................................................199
38 Tinea Cruris ......................................................................................................203
39 Tinea Pedis ........................................................................................................207
40 Tinea Versicolor ................................................................................................211
Infestations
41 Cutaneous Larva Migrans ................................................................................217
42 Head Lice ..........................................................................................................221

43 Insect Bites and Papular Urticaria....................................................................225
44 Scabies ................................................................................................................233
Papulosquamous Diseases
45 Lichen Nitidus ..................................................................................................241
46 Lichen Planus (LP)............................................................................................243
47 Lichen Striatus ..................................................................................................247
48 Pityriasis Rosea..................................................................................................249
49 Psoriasis..............................................................................................................253
50 Seborrheic Dermatitis ......................................................................................257


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Table of Contents

ix

Vascular Reactions
51 Cutis Marmorata ..............................................................................................263
52 Erythema Multiforme (EM)/Stevens-Johnson syndrome (SJS) ....................267
53 Toxic Epidermal Necrolysis (TEN) ..................................................................271
54 Urticaria ............................................................................................................275
Vascular Lesions
55 Cutis Marmorata Telangiectatica Congenita (CMTC) ..................................281

56 Infantile Hemangioma......................................................................................285
57 Kasabach-Merritt Phenomenon ......................................................................295
58 Pyogenic Granuloma ........................................................................................299
59 Telangiectasias ..................................................................................................303
60 Vascular Malformations....................................................................................309
Disorders of Pigmentation
Hypopigmentation
61 Albinism ............................................................................................................319
62 Pityriasis Alba ....................................................................................................323
63 Post-Inflammatory Hypopigmentation ..........................................................325
64 Vitiligo................................................................................................................327
Hyperpigmentation
65 Acanthosis Nigricans ........................................................................................333
66 Acquired Melanocytic Nevi ..............................................................................337
67 Café au Lait Macules ........................................................................................341
68 Congenital Melanocytic Nevi (CMN) ............................................................345
69 Ephelides ............................................................................................................349
70 Lentigines ..........................................................................................................351
71 Mongolian Spots ..............................................................................................355
Lumps and Bumps
72 Cutaneous Mastocytosis ..................................................................................359
73 Granuloma Annulare ........................................................................................363
74 Juvenile Xanthogranuloma ..............................................................................367
Bullous Diseases
75 Childhood Dermatitis Herpetiformis..............................................................371
76 Epidermolysis Bullosa (EB) ..............................................................................375
77 Linear IgA Dermatosis ......................................................................................381


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Genodermatoses
78 Ichthyosis ..........................................................................................................387
79 Incontinentia Pigmenti ....................................................................................393
80 Neurofibromatosis (NF) ..................................................................................397
81 Tuberous Sclerosis Complex (TSC) ................................................................403
Hair Disorders
82 Alopecia Areata..................................................................................................411
83 Loose Anagen Syndrome ..................................................................................417
84 Telogen Effluvium ............................................................................................421
85 Traction Alopecia ..............................................................................................425
86 Trichotillomania................................................................................................427
Skin Disorders in Neonates/Infants
87 Diaper Dermatitis ............................................................................................433
88 Eosinophilic Pustular Folliculitis ....................................................................439
89 Erythema Toxicum............................................................................................441
90 Infantile Acropustulosis ....................................................................................445
91 Intertrigo............................................................................................................447
92 Miliaria ..............................................................................................................449
93 Nevus Sebaceus (of Jadassohn)........................................................................451

94 Transient Neonatal Pustular Melanosis ..........................................................453
Drug Eruptions
95 Drug Hypersensitivity Syndrome ....................................................................457
96 Exanthematous and Urticarial Drug Reactions ..............................................461
97 Fixed Drug Eruption ........................................................................................465
98 Serum Sickness–Like Reaction ........................................................................469
Cutaneous Manifestations of Rheumatologic Diseases
99 Juvenile Dermatomyositis (JDM) ....................................................................475
100 Systemic Lupus Erythematosus (SLE) ............................................................483
Other Disorders
101 Kawasaki Disease ..............................................................................................497
102 Lichen Sclerosus et Atrophicus (LSA) ............................................................503
Index ........................................................................................................................507
Figure Credits ........................................................................................................554


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Foreword
Concerns relating to the skin are common reasons for parents to seek medical
care for their children. Data from several sources indicate that up to 20% of child
visits to pediatricians or family physicians involve a dermatologic problem, either
as the primary reason for the visit, a secondary concern, or an incidental finding
on physical examination. The volume of skin-related concerns and the supplydemand crunch for dermatologic referrals mandate that primary care physicians

who care for children are prepared to recognize, diagnose, and treat common
cutaneous disorders.
This guide was designed to be a practical, easy-to-use tool for the busy practitioner. It is not an exhaustive reference; instead it provides a concise summary of
the most common dermatologic disorders, with a standardized format that
includes a brief background, physical findings, diagnostic modalities, and treatment approaches. Each chapter includes a useful “Look-alikes” table to assist in
differential diagnosis and, when applicable, a “Resources for Families” section,
which provides links to patient information and/or support groups. Chapters to
help enhance skills in recognizing and describing skin disorders, performing and
interpreting diagnostic tests, and managing skin disease also are included. The
accompanying color photographs have been selected to illustrate some cardinal
features of each disorder.
We hope this guide fulfills a need for the practitioner caring for children who
wants a quick dermatology reference.
D.P.K.
A.J.M.


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Editors’ Note
The information contained in this text has been gleaned from reviews of multiple
scientific papers and textbooks. The materials have been synthesized into what
we hope is a coherent, easy-to-read style. Individual references have not been
included in an effort to keep the size of this work practical for a quick reference

guide. Some textbook references are listed here and we invite the reader to refer to
updated medical publications for further information or contemporary
scientific updates.
Daniel P. Krowchuk, MD
Anthony J. Mancini, MD

Textbook References
Bolognia JL, Jorizzo JL, Rapini RP, et al. Dermatology. London, UK: Elsevier; 2003
Cohen BA. Pediatric Dermatology. 3rd ed. Edinburgh, UK: Elevier Mosby; 2005
Eichenfield LF, Frieden IJ, Esterly NB. Textbook of Neonatal Dermatology.
Philadelphia, PA: W.B. Saunders; 2001
Paller AS, Mancini AJ. Hurwitz Clinical Pediatric Dermatology. 3rd ed. London,
UK: Elsevier; 2006
Schachner LA, Hansen RC, Happle R, et al. Pediatric Dermatology. 3rd ed.
London, UK: Mosby; 2003
Weston WL, Lane AT, Morelli JG. Color Textbook of Pediatric Dermatology.
3rd ed. St. Louis, MO: Mosby; 2002


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Chapter 1

Approach to the Patient With a Rash

Introduction
Recognizing and describing skin lesions accurately is essential to the diagnosis
and differential diagnosis of skin disorders.
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■

The first step is to identify the primary lesion, defined as the earliest lesion
and the one most characteristic of the disease.
Next note the distribution, arrangement, and color of primary lesions, along
with any secondary change (eg, crusting or scaling).

Types of Primary Lesions
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■

Flat lesions
– Macule: a small (<1 cm), circumscribed area of color change without
elevation or depression of the skin (Figure 1.1)
– Patch: a larger (≥1 cm) area of color change without skin elevation or
depression (Figure 1.2)
Elevated lesions
– Solid lesions

FIGURE 1.1. Café au lait macules in a patient who has
neurofibromatosis type 1.

FIGURE 1.2. A port wine stain. An
erythematous patch.



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• Papules (<0.5 cm in diameter) (Figure 1.3)
• Nodules (Ն0.5 cm in diameter) (Figure 1.4)
• Wheals: pink, rounded, or flat-topped elevations due to edema in the
skin (Figure 1.5)
• Plaques: plateau-shaped structures often formed by the coalescence of
papules (Figure 1.6)
– Fluid-filled lesions
• Vesicles: <0.5 cm in diameter and filled with serous or clear fluid
(Figure 1.7)

FIGURE 1.3. Neonatal acne. Erythematous
papules and papulopustules.
FIGURE 1.4. Nodules representing
neurofibromas in a patient who has
neurofibromatosis type 1.


FIGURE 1.5. Pink wheals in a patient who
has urticaria.

FIGURE 1.6. Scaling plaques, plateau-like
lesions, are observed in psoriasis.


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Approach to the Patient With a Rash

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• Bullae: 0.5 cm in diameter and typically filled with serous or clear fluid
(Figure 1.8)
• Pustules: <0.5 cm in diameter and filled with purulent material
(Figure 1.9)
• Cysts: 0.5 cm in diameter; represent sacs containing fluid or semisolid
material (Unlike in bullae, the material within a cyst is not visible from
the surface.)

FIGURE 1.7. Vesicles, as seen here in varicella, are

filled with clear or serous fluid.

FIGURE 1.9. Pustules are filled with purulent material.
This patient has folliculitis.

FIGURE 1.8. Bullae, filled with clear fluid, are
observed in chronic bullous disease
of childhood.


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Pediatric Dermatology
A Quick Reference Guide

Depressed lesions
– Erosions: superficial loss of epidermis with a moist base (Figure 1.10)
– Ulcers: deeper lesions extending into the dermis or below
FIGURE 1.10. Erosions, as seen in
this infant who has acrodermatitis

enteropathica, represent a superficial
loss of epidermis.

Distribution of Lesions
Certain disorders are characterized by unique patterns of lesion distribution.
For example,
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Atopic dermatitis in children and adolescents typically involves the antecubital
or popliteal fossae.
Seborrheic dermatitis in adolescents commonly involves not only the scalp,
but also the eyebrows and nasolabial folds.
Lesions of psoriasis are often seen in areas that are traumatized such as the
extensor surfaces of the elbows and knees.
Acne is limited to the face, back, and chest, sites of the highest concentrations
of pilosebaceous follicles.

Arrangement of Lesions
The arrangement of lesions also may provide a clue to diagnosis. Some examples
include
■

■


■

Linear: contact dermatitis due to plants (eg, poison ivy) (Figure 1.11), lichen
striatus, and incontinentia pigmenti; may also occur in epidermal nevi,
psoriasis, and warts
Grouped: herpes simplex virus infection (Figure 1.12), warts, molluscum
contagiosum
Dermatomal: herpes zoster (Figure 1.13)


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Chapter 1
Approach to the Patient With a Rash

FIGURE 1.11. A linear arrangement of papules or vesicles often occurs in contact
dermatitis due to poison ivy.

FIGURE 1.12. Grouped vesicles are characteristic of herpes simplex virus infection on the skin.

FIGURE 1.13. Lesions of herpes zoster appear in a dermatomal distribution.

5



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Annular (ie, ring-shaped): tinea corporis (Figure 1.14), granuloma annulare,
erythema migrans, lupus erythematosus
FIGURE 1.14. An annulus
(ie, ring-shaped lesion) is typical
of tinea corporis.

Color
■

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■
■

Erythematous: pink or red (When erythematous lesions are observed, it is

important to note if they blanch. If the red cells are within vessels as
occurs in urticaria, compression of the skin forces the cells into deeper
vessels and blanching occurs. However, if the cells are outside vessels, as
occurs in forms of vasculitis, blanching will not occur. Non-blanching
lesions are termed petechiae, purpura, or ecchymoses.)
Hyperpigmented: tan, brown, or black
Hypopigmented: amount of pigment decreased, but not entirely absent
Depigmented: all pigment absent (as occurs in vitiligo)

Secondary Changes
Alterations in the skin that may accompany primary lesions include
■

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■

Crusting: dried fluid; commonly seen following rupture of vesicles or bullae
(as occurs with the “honey-colored” crust of impetigo)
Scaling: represents epidermal fragments that are characteristic of several
disorders, including fungal infections (eg, tinea corporis) and psoriasis
Atrophy: an area of surface depression due to absence of the epidermis,
dermis, or subcutaneous fat; atrophic skin often is thin and wrinkled
Lichenification: thickening of the skin from chronic rubbing or scratching
(as occurs in atopic dermatitis); as a result, normal creases appear more
prominent



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Chapter 2

Diagnostic Techniques
Introduction
Several procedures can assist the clinician in diagnosing skin problems. Discussed
here are the potassium hydroxide preparation, fungal culture, mineral oil preparation, and Wood light examination.

Potassium Hydroxide (KOH) Preparation
Used to identify fungal elements (eg, spores, hyphae, and pseudohyphae) in skin,
hair, or nail samples. The procedure is as follows:
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■

■

■
■
■

Using the edge of a glass microscope slide or #15 scalpel, scrape the skin and

collect fragments or hair remnants on a second glass microscope slide. If
sampling a nail, use a scalpel blade to scrape the underside of the nail (or its
surface if superficial infection is suspected) and collect the debris obtained.
Cover the specimen on the glass slide with a cover slip.
Apply 1 to 2 drops of 10% to 20% KOH to the edge of the cover slip. Capillary
action will draw the liquid under the entire cover slip.
Gently heat the slide with an alcohol lamp or match taking care to avoid
boiling (which causes the KOH to crystallize and makes interpretation of
the preparation difficult).
Gently compress the cover slip to further separate skin fragments.
Scan the preparation initially under low power (40–100x).
Examine any suspicious areas under higher power (100–430x) for
– Branching hyphae or spores: characteristic of dermatophyte infections
of the skin or nails (eg, tinea corporis, tinea pedis, tinea cruris,
onychomycosis) (Figure 2.1).

FIGURE 2.1. Potassium hydroxide preparation showing branching hyphae.


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– Spores within hair fragments (ie, an endothrix infection): characteristic
of the most common form of tinea capitis in the United States caused
by Trichophyton tonsurans (Figure 2.2). If tinea capitis is caused by
Microsporum canis (approximately 5% of all cases), hyphae or spores
will be seen on the outside of hair shafts (ie, an ectothrix infection).
– Pseudohyphae and spores: seen in infections with Candida species
(Figure 2.3).

FIGURE 2.2. Potassium hydroxide preparation in tinea capitis caused by Trichophyton
tonsurans. The hair fragment is filled with small spheres (ie, arthrospores).

FIGURE 2.3. Pseudohyphae and spores are characteristic of
infection caused by Candida species.


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Chapter 2
Diagnostic Techniques

– Spores and short hyphae (ie, “spaghetti and meatballs”): seen in tinea
versicolor (Figure 2.4).


FIGURE 2.4. In tinea versicolor, the potassium hydroxide preparation reveals short
hyphae (large arrow) and spores (small arrow) (“spaghetti and meatballs”).

Fungal Culture
■

Sampling techniques
– If sampling the skin: Using the edge of a glass microscope slide or #15
scalpel, scrape the lesion and collect scale on a glass microscope slide.
– If sampling a nail: Use a scalpel blade to scrape the underside of the nail
(or its surface if superficial infection is suspected), and collect the debris
on a glass microscope slide or folded sheet of paper; alternatively, use a
nail clipper to obtain nail clippings.
– If sampling the scalp
• Use the edge of a glass microscope slide or #15 scalpel to scrape the
affected area, collecting scale and hair remnants (ie, black dot hairs)
onto a glass microscope slide.
• Alternatively, moisten a cotton-tipped applicator with tap water, rub
the affected area of the scalp, and inoculate the fungal culture medium
with the swab. (If fungal culture medium is not available, a culturette
swab system may be used to collect and transport the specimen to
the laboratory.)

9


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Pediatric Dermatology
A Quick Reference Guide

Transfer the material collected to the fungal medium (typically dermatophyte
test medium [DTM] or Mycosel agar) and process appropriately.
– Leave the cap slightly loose to permit air entry.
– If fungal culture medium is not available, transfer the specimen in a sterile
glass tube or other container to the laboratory.
In the presence of a pathogenic fungus, DTM will change from yellow to red
in 1 to 2 weeks (Figure 2.5).
FIGURE 2.5. Uninoculated dermatophyte test medium is yellow (left).
In the presence of a pathogenic fungus
the medium becomes red (right).

Mineral Oil Preparation for Scabies
■

■


■
■
■
■

Place a small drop of mineral oil on a suspicious burrow, papule, or vesicle
that has not been traumatized by the patient.
Using a #15 scalpel blade oriented parallel to the skin surface, scrape the
lesion. Because scabies mites live in the epidermis, it is not necessary to
scrape deeply; however, some bleeding is common with the procedure.
Transfer the material to a drop of mineral oil on a glass microscope slide.
Repeat the process for several other suspicious lesions.
Cover the sample on the glass slide with a cover slip.
Examine at low power for the presence of mites, eggs, or fecal material
(Figure 2.6).


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Chapter 2
Diagnostic Techniques

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FIGURE 2.6. A mineral oil preparation in a patient who has scabies reveals eggs (large arrow)
and mite fecal material (ie, scybala) (small arrow).

Wood Light Examination
Examination of the skin using a Wood light in a darkened room may assist in the
diagnosis of several conditions.
■

■

■

■

Erythrasma (a superficial Corynebacterium infection): Affected areas fluoresce
a coral-red color.
Tinea capitis: Wood light examination is only useful in the recognition of
a minority of cases (perhaps 5%) of tinea capitis caused by Microsporum
species. Green fluorescence does not occur when infections are caused by
T tonsurans.
Tinea versicolor (caused by the yeast Pityrosporum ovale): Affected areas may
fluoresce a yellow-gold color.
Diseases characterized by hypopigmentation or depigmentation: In lightly
pigmented individuals, examining the skin with a Wood light may assist in
identifying lesions of vitiligo or ash-leaf macules of tuberous sclerosis.


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