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Edited by E Steve Roach, Van S Miller. Cambridge: Cambridge University Press, 2004, pp 325, £120.00 (hardback). ISBN 0 52 78153 1
Most doctors either love or hate “the neurocutaneous disorders”. These words can provoke flashbacks to examination agony, or to diagnostic triumph. They plunge some into uncertainty, and transport others to scholarly heights. But whatever your experience, this book is for you, or at least for your library. The editors, American neurologists, amply achieve their aim “to provide readily accessible information about the clinical features and natural history of these rare conditions as well as an understanding of their genetic basis and molecular mechanisms”.
Introductory chapters providing useful lists and background genetics are followed by comprehensive coverage of individual disorders. Some are well known—for example, neurofibromatosis, tuberous sclerosis, and Sturge-Weber syndrome. Rarer classics that roll off the dermatological tongue find their place here: ataxia telangiectasia, incontinentia pigmenti, xeroderma pigmentosum. Inclusion of conditions that uncharacteristically affect the nervous system does not detract: any disorder of blood vessels can affect the brain—for example, Ehlers-Danlos syndrome, blue rubber bleb nevus syndrome, and hereditary haemorrhagic telangiectasia. In some cases the neurological component is limited to the eyes (pseudoxanthoma elasticum) or peripheral nerve (macrodactyly-nerve fibrolipoma).
The material is well organised and well edited, with each chapter following the same plan: clinical manifestations (dermatological, neurological, radiological, etc), followed by genetic basis and management issues. Gorlin on Gorlin’s syndrome is, as ever, a delight. Well chosen references and accurate indexing combine to make the book both authoritative and user friendly. Most genetics books are out of date as soon as they are published, but every relevant new gene has been included in this one. The sparse, mostly black and white illustrations are at first sight a disappointment. However, the pictures are well chosen to illustrate relevant points: restrained compared with dermatological atlases, but entirely adequate.
Errors and omissions are few and relatively unimportant. Epidermal naevus due to keratin 1 or 10 mutation is not (as stated on page 20) a neurocutaneous disorder, because keratins are not expressed in the nervous system. Linear and whorled hypermelanosis, contrary to the statement in the section on incontinentia pigmenti, is sometimes associated with neurological abnormalities. Perhaps those skin disorders associated with deafness should be included as neurocutaneous disorders, such as KID syndrome (keratitis/ichthyosis/deafness) and deafness with palmoplantar keratoderma due to connexin mutations. Two steroid sulphatase deficiency disorders with developmental delay are omitted, namely X-linked ichthyosis with contiguous deletion of a mental retardation gene, and multiple sulphatase deficiency.
This book radiates enthusiasm and excitement. These are the disorders where clinical diagnostic skills really matter. The accessibility of the skin helps us to understand the inaccessible nervous system. The future is bright, the future is genetic. For most of these conditions the molecular basis has been elucidated in the past 10 years, leading not only to more accurate diagnosis, and more informed genetic counselling, but also to a greater understanding, and the hope of effective treatment for these once incurable disorders. You may still be unable to list four cutaneous markers of tuberous sclerosis, but at least you know where to look them up.