Ethnic Dermatology E-Book

Ophelia E. Dadzie

• Herausgeber: John Wiley & Sons
• Kategorie: Fachliteratur
• Sprache: Englisch

Seitenzahl: 734

Veröffentlichungsjahr: 2013

Beschreibung

ETHNIC DERMATOLOGY
Principles and Practice

Richly pigmented skin is the most common skin type internationally

Historically, dermatology has focused on white skin. But rich pigmentation can lead to differences in presentation, disease course and outcome, and reaction to treatment. Some dermatologic conditions are seen either predominantly or exclusively in richly pigmented skin.

Ethnic Dermatology: Principles and Practice provides a practical approach to the dermatology of nonwhite skin. Written from a global perspective to include Asian, African-Caribbean and North African skin types, it covers all the bases of dermatology including:

• Grading scales in dermatologic disease
• Pediatric dermatology
• Dermatology and systemic disease
• Drug eruptions
• Hair and scalp disorders
• Cosmetic dermatology.

With a central focus on practical action from an international cast of authors, Ethnic Dermatology: Principles and Practice gives you the clinical tools you need when skin color matters.

Leseprobe

Contents

List of Contributors

Foreword

Preface

List of Abbreviations

CHAPTER 1 Defining Ethnic Dermatology: Challenges, Limitations, and Merits

CHAPTER 2 Skin Semiology and Grading Scales

Introduction

Pigmentation and color

Other differences in skin semiology

Grading scores/scales

CHAPTER 3 Common Skin Conditions and Ethnicity

Introduction

Psoriasis

Adult seborrheic dermatitis

Xerosis (dry skin)

Contact dermatitis

Atopic dermatitis

Palmar and plantar keratoderma

Pityriasis rosea

Lichenification and prurigo nodularis

Primary cutaneous amyloidosis

Disseminate and recurrent infundibulofolliculitis

Prurigo pigmentosa

Acne

Rosacea

Facial Afro-Caribbean childhood eruption

Lichen planus

Lichen nitidus

Confluent and reticulate papillomatosis

Autoimmune blistering disorders

Pediculosis capitis

T-cell lymphoma

Skin lesions in relation to traditional therapies

CHAPTER 4 Pediatric Dermatology and the Ethnic Patient

Introduction

Dermal melanocytosis

Transient neonatal pustular melanosis

Acropustulosis of infancy

Kawasaki’s disease

Childhood-onset systemic lupus erythematosus and cutaneous lupus erythematosus

Neonatal lupus erythematosus

Traction folliculits/alopecia

Tinea capitis

Atopic dermatitis

Ichthyosis

Keratosis pilaris

Lichen striatus

Epidermal nevus

Phytophotodermatitis

Recognizing jaundice

Measles

Vascular lesions

Childhood granulomatus periorificial dermatitis

Neurofibromatosis type 1

Molluscum contagiosum

Seborrheic dermatitis

Acquired acrodermatitis enteropathica

CHAPTER 5 Cutaneous Manifestations of Systemic Diseases

Introduction

Lupus erythematosus or lupic disease

Scleroderma (systemic sclerosis)

Dermatomyositis

Sarcoidosis

Behçet’s disease

Acanthosis nigricans

Sickle cell disease

Conclusion

CHAPTER 6 Drug Eruptions and Ethnicity

Introduction

Clinical presentation

Incidence

Explaining the observed ethnic differences

Practical conclusions

CHAPTER 7 Photodermatoses and Phototherapy in the Ethnic Patient

Introduction

Photodermatoses

Ultraviolet-based and laser therapy

Conclusion

CHAPTER 8 HIV-related Skin Diseases

Introduction

Infectious skin diseases

Inflammatory skin diseases

Neoplastic skin diseases

Hair and nail disorders

HIV-related skin diseases associated with antiretroviral therapy

CHAPTER 9 Benign Skin Tumors and Cysts in the Ethnic Patient

Introduction

Dermatosis papulosa nigra

Syringoma

Vellus hair cysts

Epidermoid cysts

Granular cell tumor

Papillary eccrine adenoma

Lipoma

Pseudolymphoma

CHAPTER 10 Malignant Skin Tumors and the Ethnic Patient

Introduction

Melanoma

Basal cell carcinoma

Squamous cell carcinoma

Dermatofibrosarcoma protuberans

Cutaneous lymphoma

Kaposi’s sarcoma

CHAPTER 11 Treatment of Keloids and Scars

Introduction

Keloid and scar treatment

First-line therapy

Second-line therapy

Third-line therapy

Novel therapies and the future

Viral hypothesis and possible future therapies

CHAPTER 12 Vitiligo: Clinical Presentation and Management

Introduction

Definition and types of vitiligo

Prevalence and affected sites

Differential diagnoses

Quality of life in vitiligo patients

Etiology and pathogenesis

Histopathology

Natural history and prognosis

Investigations

Management and treatment

Conclusion

CHAPTER 13 Other Causes of Hypopigmentation: What Not to Miss

Introduction

Pathophysiology of hypopigmentation

Clinical assessment

Hypopigmentation: the causes

Conclusion

CHAPTER 14 Facial Hyperpigmentation: A Practical Approach to Diagnosis and Management

Introduction

Macules

Patches

Generalized hyperpigmentation

Conclusion

CHAPTER 15 Hair and Scalp Disorders in Women of African Descent

Introduction

Pathogenesis

Prevalence of hair and scalp disease

Clinical assessment

Clinical features and management of specific hair and scalp disorders

Conclusions

CHAPTER 16 Dermatological Disorders in Men of African Descent

Introduction

Pseudofolliculitis barbae

Acne keloidalis nuchae

Dissecting cellulitis of the scalp

Folliculitis decalvans

Keloids

CHAPTER 17 Hair Transplantation in People of African Descent

Introduction

Biology of afro-textured hair and skin: implications for hair transplantation

Indications and pre-procedure evaluation

History of hair transplantation

Harvesting technique

Dissection of donor tissue

Graft implantation

Postoperative care

Complications

Conclusion

CHAPTER 18 Lasers and the Ethnic Patient

Introduction

Acne scars

Acne

Photorejuvenation

Laser-assisted hair reduction

Skin tightening

Lipolysis with energy-based devices

Most common complications

Conclusion

CHAPTER 19 Cosmetic Dermatology in Ethnic Skin

Introduction

Chemical peels

Fillers

Botulinum toxin

Conclusion

CHAPTER 20 Cosmetic Use of Skin Lightening Products

Introduction

Epidemiology

Pharmacological data

Complications

Sociocultural data

Management

Conclusion

Index

This edition first published 2013, © 2013 by John Wiley & Sons, Ltd.

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Library of Congress Cataloging-in-Publication Data

Ethnic dermatology : principles and practice / edited by Ophelia E. Dadzie, Antoine Petit, Andrew F. Alexis.p. ; cm.Includes bibliographical references and index.

ISBN 978-0-470-65857-4 (hardback : alk. paper) – ISBN 978-1-118-49778-4 (O-book) –ISBN 978-1-118-49779-1 (Mobi) – ISBN 978-1-118-49783-8 (epub) – ISBN 978-1-118-49784-5 (ePDF/ebook)I. Dadzie, Ophelia E. II. Petit, Antoine. III. Alexis, Andrew F.[DNLM: 1. Skin Diseases–ethnology. 2. Ethnic Groups. 3. Skin Diseases–diagnosis. 4. Skin Diseases–therapy. WR 140]616.5–dc23

2012029833

A catalogue record for this book is available from the British Library.

Wiley also publishes its books in a variety of electronic formats. Some content that appears in print may not be available in electronic books.

Cover image: © Sergej Khackimullin – Fotolia.comCover design by Andy Meaden

List of Contributors

Nita AgarConsultant Dermatologist, Royal Prince Alfred HospitalSenior Lecturer, University of SydneySydney, AustraliaFatima Al-FaresiSpecialist Dermatologist, Associate Program DirectorDermatology Residency ProgramTawam Hospital/Johns Hopkins MedicineAl Ain, United Arab EmiratesMahreen AmeenDepartment of DermatologyRoyal Free London NHS Foundation TrustLondon, UKBrian BermanProfessor of Dermatology and MedicineUniversity of Miami Miller School of MedicineMiami, FL, USAMarcelyn ColeyResidentDepartment of DermatologyState University of New York Downstate Medical CenterNew York, NY, USAMoussa DialloServices MédicauxHôpital PrincipalDakar, SenegalViktoria EleftheriadouResearch AssociateCentre of Evidence-Based DermatologyUniversity of NottinghamNottingham, UKOusmane FayeAssistant Professor of DermatologyFaculty of MedicineUniversity of BamakoCNAM Ex Institut MarchouxBamako, MaliLeila FergusonDermatology Specialty RegistrarBasildon University Hospital Essex Basildon, UKKristian FiguerasSenior Research AssociateBaumann Cosmetic and Research InstituteMiami Beach, FL, USACamille FitoussiConsultant DermatologistGroupe Médical Charcot256 Rue de BellevilleParis, FranceHassan I. GaladariAssistant Professor of DermatologyFaculty of Medicine and Health SciencesUnited Arab Emirates UniversityTawam Hospital/Johns Hopkins MedicineAl Ain, United Arab EmiratesRichard H. HugginsSenior Staff PhysicianDepartment of DermatologyHenry Ford HospitalDetroit, MI, USANonhlanhla P. KhumaloAssociate Professor of DermatologyDivision of DermatologyGroote Schuur and Red Cross Children’s HospitalsUniversity of Cape TownSouth AfricaHenry W. LimChairman, Department of DermatologyC.S. Livingood Chair in DermatologyHenry Ford HospitalDetroit, MI, USAFatimata LyHead, Department of DermatologyInstitute for Social HygieneDakar, SenegalAntoine MahéDepartment of DermatologyHôpital Pasteur (HCC) – ColmarColmar, FranceJean-Jacques MorandProfessor of DermatologyDepartment of DermatologyMilitary Hospital Sainte AnneToulon, FranceSanjeev V. MulekarSpecialist DermatologistNational Center for Vitiligo and PsoriasisRiyadh, Saudi ArabiaDupe L. OdunsiSenior House OfficerKing’s College HospitalLondon, UKBridget OgawaConsultant DermatologistGhana Health ServiceAccra, GhanaFrederick N. QuarlesPractitionerQuarles DermatologyHampton, VA, USAAnthony RossiDepartment of DermatologySt. Luke’s Roosevelt HospitalNew York, NY, USAJean-Claude RoujeauEmeritus ProfessorUniversité Paris-EstCréteil, FranceJack SmadjaDepartment of DermatologyAPHP Hôpital Saint-LouisParis, FranceAmeet TailorCharing Cross HospitalImperial College Healthcare NHS TrustLondon, UKPatricia A. TreadwellProfessor of PediatricsIndiana University School of MedicineIndianapolis, IN, USAMartha H. VieraDepartment of Dermatology and Cutaneous SurgeryUniversity of Miami Miller School of MedicineMiami, FL, USAAlejandra C. VivasDepartment of Dermatology and Cutaneous SurgeryUniversity of Miami Miller School of MedicineMiami, FL, USAHeather Woolery-LloydDirector of Ethnic Skin CareUniversity of MiamiDepartment of Dermatology and Cutaneous SurgeryCosmetic Medicine and Research InstituteMiami, FL, USA

Foreword

Ethnic Dermatology is being published during a ­renaissance in the study of human variation, when ­studies of the significance of variation in human skin have gained new importance and legitimacy. For most of the history of dermatology, human skin was “White,” northern European skin. White skin was the normal human condition, from which all others deviated. Dermatology rose as an independent discipline during the late 18th and early 19th centuries, at the same time as naturalists and anthropologists were describing human races and philosophers were arguing for hierarchical ranking of those races. People with moderately or darkly pigmented skin were viewed by many at that time as lesser beings and the normal properties of their skin were seen as pathological by definition. The need for books like Ethnic Dermatology today arose from the misconceptions about the nature of normal variation in human skin that developed in those benighted times. As institutional and governmentally sanctioned racism declined worldwide in the late 20th century, knowledge and appreciation of the importance of variation in the properties of human skin increased. This promising trend was retarded, ironically, by the power of popular social movements which advocated equality among races and sexes in all matters and which viewed the study of human variation as inherently divisive and socially destructive. Dermatology, more than other medical specialties, is subject to the vicissitudes of social and political movements because it deals with the organ that is humankind’s most visible interface with the physical and social environment.

Dermatologists working to describe and study “ethnic” skin or skin of color and its diseases face many practical problems, one of the most serious being an impoverished vocabulary with which to describe variation. The glossary of descriptive medical terms for skin pigmentation is bereft of accurate and precise words to describe hues, shades, and tints of skin color. “Darkly,” “richly,” and “moderately” pigmented are commonly used in medicine and are socially acceptable, but are miserably imprecise and are less exact than the rich colloquialisms they seek to replace. The Fitzpatrick scale of skin phototypes, which has dominated dermatology for nearly a half century, is also deficient because it is based on subjective assessment of one phenotypic trait, tanning ability. While this classification method can broadly inform us of an individual’s sun sensitivity and likelihood of developing skin cancer, tanning ability is not determined by a single gene or a single unique set of genes nor is it necessarily informative of other immunological or physiological properties of skin that are relevant to disease susceptibility. Genetic and genomic studies have revealed that pigmentation phenotypes have evolved multiple times as modern humans have dispersed out of and back into the tropics. We now know that lightly pigmented (“White”) skin seen in natives of Berlin and Beijing, for example, was the product of two independent genetic mutation events leading to the evolution of two depigmented human lineages that came to inhabit northwestern Europe and northeastern Asia. The classification of these two individuals as Fitzpatrick type II is of limited usefulness. Similarly, natives of Brasilia, Cape Town, and Naples who are classified as Fitzpatrick type IV are likely to have three different sets of pigmentation gene polymorphisms contributing to their enhanced tanning abilities. The point here is that we are in need of new ways of defining and describing the normal range of variation present in healthy human skin because the current vocabulary and scales for describing variation are inadequate and outdated. The genetic bases for the complex mixtures of melanins and keratins found in skin, and for the interaction of these with various immunoglobulin isotypes, are now beginning to be understood and their significance for health and disease appreciated. As this body of information grows, and our understanding of individual responses to environmental insults develops apace, dermatology will truly come of age.

The synthesis of knowledge on skin and skin diseases presented in Ethnic Dermatology is inspiring and ­provides the foundation for a modern and comprehensive science of dermatology that is based on an inclusive concept of “normal human skin,” including its aging and scarring characteristics and susceptibility to disease. Specialists in ethnic dermatology will find this book to be an excellent guide, but also a call to action. This field requires much more research and many more avid clinicians and ­scientists interested in carrying out that research. This book is your starting point.

Nina G. Jablonski, PhDDistinguished Professor of AnthropologyPennsylvania State UniversityPennsylvania, PA, USA

Preface

In the face of life’s many challenges we have to ask ­ourselves why do we do what we do? This simple question is one we have had to reflect upon prior to and during the writing and editing of this textbook. For us the answer to this question is simple: a need to make a difference and/or impact in our community, combined with a genuine interest and passion for the subject matter.

Broadly speaking, mainstream dermatology in most western countries continues to have a eurocentric ­standard and viewpoint, despite an increasing interest worldwide in the issue of ethnic dermatology. This has primarily been driven by the changing demographics of most western countries, coupled with the emerging ­economies of many African and Asian countries. While several textbooks now exist on this topic, most originate from the USA, giving an American perspective to this issue.

The purpose of Ethnic Dermatology: Principles and Practice is to provide a comprehensive, yet practical ­perspective of the subject matter. Both medical and ­cosmetic dermatology are extensively covered in this textbook. Ample use of good-quality clinical images ­supplements the text, which are all clinically relevant. Furthermore, there is an excellent foreword written by Professor Nina Jablonski discussing the issue of terminologies pertaining to ethnic dermatology.

This textbook will suit clinical dermatologists, primary care physicians, physicians from other specialties, and specialist nurses. It is our hope that all will find this book of direct relevance to their daily clinical practice. Long-term, we also hope that textbooks such as this will encourage acceptance and incorporation of ethnic ­dermatology into mainstream dermatology forums in many western countries.

Ophelia E. DadzieAntoine PetitAndrew F. Alexis

List of Abbreviations

AD

atopic dermatitis

AJCC

American Joint Committee on Cancer

AKN

acne keloidalis nuchae

ALM

acral lentiginous melanoma

AP

actinic prurigo

ARV

antiretroviral drugs

ART

antiretroviral therapy

ATL

adult T-cell lymphoma

ATLL

adult T-cell lymphoma/leukemia

AZT

zidovudine

BCC

basal cell carcinoma

BMZ

basement membrane zone

CAD

chronic actinic dermatitis

CBPL

cutaneous B-cell pseudolymphoma

CCCA

central centrifugal cicatricial alopecia

CCLE

chronic cutaneous lupus erythematosus

CGPD

childhood granulomatous periorificial dermatitis

CPK

creatine phosphokinase

CRP

confluent and reticulate papillomatosis

cSLE

childhood-onset systemic lupus erythematosus

CTCL

cutaneous T-cell lymphoma

CTGF

connective tissue growth factor

CTPL

cutaneous T-cell pseudolymphoma

DCS

dissecting cellulitis of the scalp

DEJ

dermo-epidermal junction

DFSP

dermatofibrosarcoma protuberans

DLCO

diffusing capacity of the lung for carbon monoxide

DMSO

dimethylsulfoxide

DOC

disorders of cornification

DPN

dermatosis papulosa nigra

DRESS

drug reactions (or rashes) with eosinophilia and systemic symptoms

DRI

disseminate and recurrent infundibulofolliculitis

EASI

Eczema Area and Severity Index

EBV

Epstein-Barr virus

ECM

extracellular matrix

EGFR

epidermal growth factor receptor

ENT

ear, nose, and throat

EV

epidermodysplasia verruciformis

EVCH

eruptive vellus hair cysts

FACE

facial Afro-Caribbean childhood eruption

FAMMM

familial atypical multiple mole melanoma syndrome

FBGCR

foreign body giant cell reaction

FPHL

female pattern hair loss

FD

folliculitis decalvans

FDE

fixed drug eruptions

FFA

frontal fibrosing alopecia

FHP

facial hyperpigmentation

FKN

folliculitis keloidalis nuchae

FSP/FST

Fitzpatrick skin phototype/type

FUE

follicular unit extraction

FVC

forced vital capacity

G6PD

glucose-6-phosphate dehydrogenase

GA

glycolic acid

GRK

G-protein-coupled receptor kinase

GVHD

graft-versus-host disease

GWAS

genome-wide association studies

HAART

highly active antiretroviral therapy

HHV

human herpes virus

HIFU

high-intensity focused ultrasound

HIV

human immunodeficiency virus

HLA

human leukocyte antigen

HPV

human papilloma virus

HS

hidradenitis suppurativa

HSE

hydrocortisone, silicon and vitamin E lotion

HSV

herpes simplex virus

HT

hair transplantation

HTLV

human T-lymphotropic virus

HTS

hypertrophic scars

IGA

Investigator Global Assessment

IGH

idiopathic guttate hypomelanosis

IH

infantile hemangioma

IK

inverse keratoderma

IP

inflammatory pigmentations

IP

Lintense pulsed light

IRS

immune reconstitution syndrome

ISD

infantile seborrheic dermatitis

IUS

intense ultrasound

IVIG

intravenous immunoglobulin

KP

keratosis pilaris

KPC

keratosis punctata of the palmar creases

KS

Kaposi’s sarcoma; keloid scars

LE

lupus erythematosus

LED

light-emitting diode

LN

lichen nitidus

LP

lichen planus

LPP

lichen planopilaris

MAI

Mycobacterium avium-intracellulare

MAP

magnesium-L-ascorbyl-2 phosphate

MASI

Melasma Area and Severity Index

MB

multibacillary

MED

minimal erythema dose

MF

mycosis fungoides

MFU

multifollicular unit

MK

marginal keratoderma

MKTP

melanocytes-keratinocytes transplantation

MPHL

male pattern hair loss

MSH

melanocyte stimulating hormone

MTB

Mycobacterium tuberculosis

MTZ

microthermal zone

NB-UVB

narrowband-UVB

NLE

neonatal lupus erythematosus

NNRTI

non-nucleoside reverse transcriptase inhibitor

NRTI

nucleoside reverse transcriptase inhibitor

NSV

nonsegmental vitiligo

OTC

over-the-counter

PA

pityriasis alba

PAR-2

protease-activated receptor 2

PASI

psoriasis area and severity index

PB

paucibacillary

PCA

primary cutaneous amyloidosis; principal component analysis

PCBCL

primary cutaneous B-cell lymphoma

PCFCL

primary cutaneous follicle centre lymphoma

PCMZL

primary cutaneous marginal zone lymphoma

PDGF

platelet-derived growth factor

PDGFR

platelet-derived growth factor receptor

PDIR

premature desquamation of the inner root sheath

PDL

pulsed dye laser

PET

positron emission tomography

PFB

pseudofolliculitis barbae

PHACES

Posterior fossa abnormalities, Hemangioma-large, segmental, Arterial lesions, Cardiac/coarctation findings, Eye abnormalities, and Sternal abnormalities

PIH

postinflammatory hyperpigmentation

PMLE

polymorphous light eruption

PPARγ

peroxisome proliferator-activated receptor gamma

PPD

paraphenylenediaminePPD

PPE

papular pruritic eruption

PPK

palmoplantar keratoderma

PR

pityriasis rosea

PUVA

psoralen plus ultraviolet light-A

PUVA

solpsoralen plus sunlight

PV

pityriasis versicolor

RegisCAR

Registry of severe cutaneous adverse reactions to drugs and collection of biological samples

RF

radiofrequency

RLX

relaxin

RSTL

relaxed skin-tension line

SA

Staphylococcus aureus

SCC

squamous cell carcinoma

SCLE

subacute cutaneous lupus erythematosus

SCORAD

Scoring Atopic Dermatitis Scale

SD

seborrheic dermatitis

SJS

Stevens-Johnson’s syndrome

SLE

systemic lupus erythematosus

SLNB

sentinel lymph node biopsy

SM

subungual melanoma

SMAS

superficial musculoaponeurotic system

SNP

single-nucleotide polymorphism

SPF

sun protection factor

SS

Sézary’s syndrome

SU

solar urticaria

SV

segmental vitiligo

TA

traction alopecia

TAC

triamcinolone acetate

TC

tinea capitis

TCA

trichloracetic acid

TEN

toxic epidermal necrolysis

TEWL

transepidermal water loss

TIS

Three-Item Severity Scale

TGF

transforming growth factor

TLR

toll-like receptors

TNM

tumor-node-metastasis

TNPM

transient neonatal pustular melanosis

TPMT

thiopurine S-methyltransferase

UVA

ultraviolet light-A

UVB

ultraviolet light-B

UVR

ultraviolet radiation

VDRL

Venereal Disease Reference Laboratory

VETF

Vitiligo European Task Force

VZV

varicella zoster virus

CHAPTER 1

Defining Ethnic Dermatology: Challenges, Limitations, and Merits

Ophelia E. Dadzie

Department of Dermatology, North West London Hospitals NHS Trust and Centre for Clinical Science and Technology, University College London Division of Medicine, London, UK

Ethnic dermatology is a term used to describe an aspect of dermatology pertaining to individuals of diverse racial and ethnic backgrounds, who have richly pigmented skin and who share broadly similar cutaneous characteristics, notably the risk of scarring and dyspigmentation in response to cutaneous trauma. The term is analogous to skin of color, which is commonly used in North America. Defining the ethnic dermatology/skin of color cohort is challenging. However, broadly speaking and in this textbook, this cohort equates to individuals with Fitzpatrick skin phototypes (FSP) ІV–VІ and/or those of African, Asian, Middle Eastern, and/or Hispanic ancestry [1–2].

Unfortunately the use of terminologies such as ethnic dermatology and/or skin of color is not without its critics [3–4]. This is because of the problems and limitations of defining individuals by race, ethnicity, and/or skin pigmentation (an inherent problem in any scientific endeavor, which Richard Dawkins refers to as “the tyranny of the discontinuous mind”) [5]. Essentially humans do not fit into neat racial or ethnic categories, but represent a continuum. Thus, at what point does someone become “black” or “white”? Since evidence indicates that modern humans originate from Africa [6], are we not all of African ancestry? Furthermore, in advocating separating and defining specific groups based on racial, ethnic and/or skin pigmentation, are we contributing to a divisive society? After all, at a genetic level, humans share more similarities than differences [6]. In addition, the use of FSP has specific limitations when applied to pigmented skin (see Box 1.1 for discussion on this issue).

There is also a risk that terms such as ethnic ­dermatology will justify studies that use skin color and/or ethnicity to validate a biological construction of race that is actually rooted in socio-historical processes [7], e.g., “scientific studies” that supported the notion that people of African race are less prone to contact ­sensitization and hence better able to handle certain ­noxious ­substances [8].

All the above represent challenging questions and difficulties that we have had to navigate before embarking on this ethnic dermatology/skin of color “journey.” In response to these challenges we first have to consider the problems faced by practicing dermatologists.

First, epidemiological studies and data obtained from hospital and/or private practices indicate that there are differences in the observed dermatoses in different ethnic/racial groups [9–10]. For instance, hair and scalp disorders are one of the major concerns in individuals with Afro-textured hair. Cultural factors also impact the range of dermatoses observed (e.g., the misuse of skin lightening agents in certain racial and/or ethnic groups and the occurrence of prayer nodules in Muslims [Fig. 1.1]). Thus, as practicing dermatologists, we need to be aware of these observed differences and the implications for managing our patients. Second, studies have highlighted deficiencies in dermato­logical educational resources and the training of dermatologists with regard to the field of skin of color/ethnic dermatology [11–12]. Finally, the demographics of most western countries is changing. This means that most practicing dermatologists need to be competent in the diagnosis and management of ­cutaneous disorders in people of diverse racial and ethnic backgrounds. For example, in 1990 the United States census revealed that 76% of the population was white; 12% black; 9% Hispanic; 2.8% Asian/Pacific Islander; and 0.7% American Indian, Eskimo, and Aleut [6]. Projections for the US population in 2050 forecast a substantial decline in the white population to approximately 53%, with an increase in other racial groups (black 14%; Hispanic 25%; Asian 8%; American Indian, Eskimo, and Aleut approaching 1%) [6]. In the United Kingdom, the 2001 census demonstrated that ethnic minorities made up 7.9% of the population, an increase of 53% compared to the previous 1991 census [13].

Box 1.1 Fitzpatrick skin phototype

The Fitzpatrick skin phototype (FSP) classification system (see also Box 1.2) [15] is used routinely by dermatologists to categorize and classify different skin types. It was initially developed by Thomas Fitzpatrick in 1975 to classify persons with “white skin” in order to select the correct initial dose of UVA for an upcoming large-scale oral PUVA photo-chemotherapy trial in the US in the mid-1970s. It was based primarily on a brief personal interview to evaluate individuals’ history of sunburn and tanning and not on phenotype (hair and eye color) [15]. The initial classification system placed all non-white/­pigmented skin in one category, skin type V. Over time this classification system evolved and skin type V was divided into three sub-groups (IV, V, and VI) to encompass the diversity observed in those with pigmented skin. Furthermore, over time phenotype has had a greater impact on this classification system. It is the author’s opinion that often phenotype is the prime method used to categorize skin types, instead of proper evaluation of ultraviolet radiation response. This is one of the main limitations of FSP as a method of classifying individuals with pigmented skin. Furthermore, studies have shown a lack of a direct correlation between constitutive skin color and response to ultraviolet radiation. For instance, individuals originating from various Asian countries encompass a diverse group and skin color does not always predict their skin phototypes [16,17]. Another limitation of FSP is that it is based on self-reported erythema sensitivity and tanning ability, and hence it is not quantitative or reliable. Furthermore, it cannot be applied for in vitro conditions. For this reason, new classification systems have been developed, such as the colorimetric classification of constitutive pigmentation by individual typology angle [18,19] and the Roberts skin classification system [20] (Box 1.2). The former is of relevance in the research setting, while the latter is of practical relevance in predicting response to trauma, prior to procedural dermatology. There are four elements to the Roberts skin classification system, which should be evaluated based on a thorough history, examination, and evaluation of test site reaction.

Box 1.2 Roberts skin type classification system

Fitzpatrick (FZ) scale: measures skin phototype

FZ1  White skin. Always burns, never tans

FZ2  White skin. Always burns, minimal tan

FZ3  White skin. Burns minimally, tans moderately and gradually

FZ4  Light brown skin. Burns minimally, tans well

FZ5  Brown skin. Rarely burns, tans deeply

FZ6  Dark brown/black skin. Never burns, tans deeply

Roberts hyperpigmentation (H) scale: propensity for pigmentation

H0   Hypopigmentation

H1   Minimal and transient (< 1 year) hyperpigmentation

H2   Minimal and permanent (> 1 year) hyperpigmentation

H3   Moderate and transient (< 1 year) hyperpigmentation

H4   Moderate and permanent (> 1 year) hyperpigmentation

H5   Severe and transient (< 1 year) hyperpigmentation

H6   Severe and permanent (> 1 year) hyperpigmentation

Glogau (G) scale: describes photoaging

G1   No wrinkles, early photoaging

G2   Wrinkles in motion, early to moderate photoaging

G3   Wrinkles at rest, advanced photoaging

G4   Only wrinkles, severe photoaging

Roberts scarring (S) scale: describes scar morphology

S0   Atrophy

S1   None

S2   Macule

S3   Plaque within scar boundaries

S4   Keloid

S5   Keloidal nodule

Based on the above and despite the valid limitations and difficulties in defining ethnic dermatology, the use of this term is helpful, given that it enables interested parties (dermatologists, other physicians, nurses, scientists, and patients) to come together to help advance this aspect of dermatology [2]. In time it is likely that advances in genomics will increase our understanding of the role of genetic variation among human populations, thereby influencing our use of terminologies such as ethnic ­dermatology and skin of color [14].

Figure 1.1 (A,B) A prayer nodule (talar callosity) located on the dorsal aspects of the left foot associated with the specific prayer stance undertaken by this devout Muslim (C).

References

1 Dadzie OE. Skin of colour: an emerging subspecialty of Dermatology. Br J Dermatol 2009; 160: 368–75.

2 Taylor SC, Cook-Bolden F. Defining skin of color. Cutis 2002; 69: 435–7.

3 Silver SE. Defining skin of color. Cutis 2003; 71: 141–2; author reply 142–3; discussion 143.

4 Elgart ML. Defining skin of color. Cutis 2003; 71: 142; author reply 142–3; discussion 143.

5 Dawkins R. The Ancestor’s Tale: A Pilgrimage to the Dawn of Life, new edn. Phoenix, 2005.

6 Taylor SC. Skin of color: biology, structure, function, and implications for dermatologic disease. J Am Acad Dermatol 2002; 46: S41–62.

7 Lee C. “Race” and “ethnicity” in biomedical research: how do scientists construct and explain differences in health? Soc Sci Med 2009; 68: 1183–90.

8 Marshall J. Skin Diseases in Africa. Cape Town, South Africa: Maskew Miller Ltd, 1964.

9 Taylor SC. Epidemiology of skin diseases in people of color. Cutis 2003; 71: 271–275.

10 Alexis AF, Sergay AB, Taylor SC. Common dermatologic disorders in skin of color: a comparative practice survey. Cutis 2007; 80: 387–94.

11 Bede T, Papier A. Disparities in dermatology educational resources. J Am Acad Dermatol 2006; 55: 687–90.

12 Nijhawan RI, Jacob SE, Woolery-Lloyd H. Skin of color education in dermatology residency programs: does residency training reflect the changing demographics of the United States? J Am Acad Dermatol 2008; 59: 615–18.

13 http://www.ons.gov.uk/ons/rel/ethnicity/focus-on-ethnicity-and-identity/focus-on-ethnicity-and-identity-summary-report/focus-on---ethnicity-and-identity-summary-report.pdf (accessed 14 August 2012).

14 Lander ES. Initial impact of the sequencing of the human genome. Nature 2011; 470: 187–97.

15 Fitzpatrick TB. The validity and practicality of sun-reactive skin types І through VІ. Arch Dermatol 1988; 124: 869–71.

16 Leenutaphong V. Relationship between skin color and cutaneous response to ultraviolet radiation in Thai. Photodermatol Photoimmunol Photomed 1996; 11(5–6): 198–203.

17 Wee LK, Chong TK, Quee DK. Assessment of skin types, skin colours and cutaneous responses to ultraviolet radiation in an Asian population. Photodermatol Photoimmunol Photomed 1997; 13(5–6): 169–72.

18 Chardon A, Cretois I, Hourseau C. Skin colour typology and sun tanning pathways. Int J Cosmet Sci 1991; 13: 191–208.

19 Del Bino S, Sok J, Bessac E, Bernerd F. Relationship between skin response to ultraviolet exposure and skin color type. Pigment Cell Res 2006; 19: 606–14.

20 Roberts WE. The Roberts skin type classification system. J Drugs Dermatol 2008; 7: 452–6.

CHAPTER 2

Skin Semiology and Grading Scales

Antoine Petit 1 and Ameet Tailor 2

1 Service de Dermatologie, APHP Hôpital Saint-Louis, Paris, France2 Charing Cross Hospital, Imperial College Healthcare NHS Trust, London, UK

Introduction

Despite technological advances in diagnostics, the art of clinical medicine still lies in the recognition and interpretation of clinical signs and symptoms. In no field is this more apparent than dermatology. In particular, the dermatologist has acquired skills for the detection of the most representative lesions of any skin disease – the so-called “elementary lesions” – and a precise evaluation of their color, size, border, thickness, number, and topography, as well as the pruritus, pain or tenderness that may be ­associated with them. This analytic approach to clinical diagnosis is a complex cognitive process complementary to a global, more intuitive process; the latter probably ­represents the ground of daily dermatological practice and allows the non-specialist to recognize most skin lesions and diseases, provided they have already seen them before. However, the “global” approach may reach its limit in unusual diagnostic situations. Such a situation may be encountered, for example, in countries where a massive campaign for the detection of leprosy has been conducted by general practitioners, nurses or other field agents who had received basic minimal instruction for the detection of leprosy lesions. As the prevalence of this disease progressively decreased due to the efficacy of these campaigns, so did the teams’ diagnostic capabilities, due to a lack of clinical experience and awareness of the differential diagnosis when confronted with a larger ­variety of skin lesions [1]. This example also reminds us that, whatever the diagnostic approach (global or analytic), the negative and positive predictive values of any clinical sign or group of signs vary with the prevalence of the disease being sought.