Dermatology Dermatology Sixth Edition EDITED BY Rachael Morris-Jones, FRCP, PhD, PCME Dermatology Consultant Kings College Hospital Denmark Hill London, UK This edition first published 2014 © 2014 by John Wiley & Sons, Ltd. © 1988, 1993, 1998, 1999, 2003, 2009 by Blackwell Publishing Ltd BMJ Books is an imprint of BMJ Publishing Group Limited, used under licence by John Wiley & Sons. 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WR 140] RL74 616.5 – dc23 2013049508 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: Patient with urticaria – photo supplied by Dr Rachael Morris-Jones. CoverdesignbyAndyMeaden. Set in 9.25/12pt MinionPro by Laserwords Private Ltd, Chennai, India 1 2014 Contents List of Contributors, vii Preface, ix Acknowledgements, xi 1 Introduction, 1 Rachael Morris-Jones 2 Psoriasis, 11 Rachael Morris-Jones 3 Management of Psoriasis, 18 Rachael Morris-Jones 4 Eczema (Dermatitis), 26 Rachael Morris-Jones 5 Urticaria and Angio-oedema, 38 Rachael Morris-Jones 6 Skin and Photosensitivity, 42 Rachael Morris-Jones 7 Drug Rashes, 48 Sarah Walsh 8 Immunobullous and Other Blistering Disorders, 55 Rachael Morris-Jones 9 Connective Tissue Disease, Vasculitis and Related Disorders, 62 Rachael Morris-Jones 10 The Skin and Systemic Disease, 70 Rachael Morris-Jones 11 Leg Ulcers, 82 Rachael Morris-Jones 12 Acne and Rosacea, 89 Rachael Morris-Jones 13 Bacterial Infections, 97 Rachael Morris-Jones 14 Viral Infections, 105 Rachael Morris-Jones 15 HIV and the Skin, 114 Rachael Morris-Jones v vi Contents 16 Fungal Infections, 121 Rachael Morris-Jones 17 Insect Bites and Infestations, 128 Rachael Morris-Jones 18 Tropical Dermatology, 135 Rachael Morris-Jones 19 Hair and Scalp, 144 Kapil Bhargava and David Fenton 20 Diseases of the Nails, 151 David de Berker 21 Benign Skin Tumours, 161 Rachael Morris-Jones 22 Premalignant and Malignant, 172 Rachael Morris-Jones 23 Practical Procedures and Skin Surgery, 183 Raj Mallipeddi 24 Lasers, Intense Pulsed Light and Photodynamic Therapy, 191 Alun V. Evans 25 Wound Management and Bandaging, 197 Bernadette Byrne 26 Formulary, 212 Karen Watson Index, 221 List of Contributors Kapil Bhargava Raj Mallipeddi St. John’s Institute of Dermatology, Guy’s and St. Thomas’ Hospitals, London, UK Cutaneous Laser and Surgery Unit, St. John’s Institute of Dermatology, St. Thomas’ Hospital, London, UK Bernadette Byrne Rachael Morris-Jones Department of Tissue viability, Kings College Hospital, London, UK Dermatology Department, Kings College Hospital, London, UK David de Berker Sarah Walsh Dermatology Department, United Bristol Healthcare Trust, Bristol, UK Kings College Hospital, London, UK Alun V. Evans Karen Watson Dermatology Department, Princess of Wales Hospital, Bridgend, UK Dermatology Department, Orpington Hospital, Orpington, Kent, UK David Fenton St. John’s Institute of Dermatology, Guy’s and St. Thomas’ Hospitals, London, UK vii Preface The Sixth Edition of the ABC of Dermatology incorporates all the On a global scale, the number of people with access to the latest scientific advances in genetics, pathophysiology and man- internet via computers or mobile devices is increasing at a rapid agement strategies whilst at the same time remaining a practical pace. This enables them to access a multitude of resources including clinical approach to dermatology. The current editor has striven those related to the diagnosis and management of human disease. to uphold the style and emphasis that Paul Buxton brought to the An informed patient can be hugely beneficial to everyone involved ABC of Dermatology to ensure that it is a valuable resource for any in the provision of healthcare; however, at times this can lead to medical and nursing practitioner who is diagnosing and managing patients becoming overly anxious or misinformed. There is an skin disease. increasing use of teledermatology in many parts of the world where In addition to a wholly practical approach to clinical dermatology, populations are a long distance away from a skin specialist from the Sixth Edition gives insights into the latest thinking around the where images of the patient’s skin complaints are taken and sent pathophysiological processes that explain the characteristic features to an expert for a virtual opinion. This can be immensely helpful; of skin disease and the current approach to its management includ- however, ultimately the gold standard for accurate diagnosis and ing the newer biological agents for treating inflammatory disease management of skin disease is still seeing patients in person prefer- and tumours. ably by a practitioner with personal knowledge and experience of The fascination of dermatology lies partly in the visual nature skin disease. of the discipline and also in one’s ability to diagnose systemic dis- I sincerely hope the Sixth Edition of the ABC of Dermatology ease through examination of the skin surface. Manifestations of an will not only introduce the reader to a fascinating clinical discipline underlying disease can form specific patterns in the skin, which in butwillalsohelpthemtodiagnoseandmanageskindiseasein some instances are pathognomonic. Internal physicians need to be whichever part of the world they are working. aware of the ‘signs posting’ of skin disorders towards the unifying We are all hugely grateful to Paul Buxton for all his hard work on underlying diagnosis. However, even a highly skilled dermatologist the previous editions of the ABC of Dermatology andIhopehewill will at times be uncertain of the diagnosis and a simple skin biopsy be proud of how the Sixth Edition has enhanced what he originally for histopathology/immunohistochemistry and/or culture is greatly created. helpful in most cases in the diagnosis and to reach a definitive man- I would like to dedicate the Sixth Edition of the ABC of Dermatol- agement plan. ogy to all the unsung heroes