Rashes associated with transplantations

Dermatological manifestations following transplantation are common but important to recognize and diagnose since they may be severe and life-threatening if not adequately and promptly treated. This chapter provides a systematic overview of the types of skin disease that may be encountered in children that have received a haematological or solid organ transplant. Complications relating to immunosuppression include an increased susceptibility to bacterial, viral, and fungal infections which may be significantly more virulent and hazardous in the context of reduced host immunity. Immune suppressant drugs may also cause drug rashes and aesthetic complications such as acne, hypertrichosis, or gingival hypertrophy, as well as longer-term risks from the development of malignancy. It is also important to recognize the range of mucocutaneous signs of acute and chronic graft versus host disease following bone marrow and solid organ transplantation which, again, may be severe and associated with significant morbidity and mortality.

Ulceration of the skin

This is a short chapter covering the causes of ulcers. The conditions are grouped into sections covering different aetiologies. Congenital conditions covered are epidermolysis bullosa, aplasia cutis, and Goltz syndrome. Infectious conditions are considered including bacterial, viral, and tropical ulcers. Traumatic ulcers including neuropathic and non-accidental causes are listed. There are further categories covering inflammation, including pyoderma gangrenosum, drug reactions, toxicity, and other causes. Oral and genital ulceration is sign-posted to the relevant chapters.

Lumps and bumps

Visible and/or palpable swellings occur in numerous diseases and many are covered in other chapters. This chapter presents an approach to making a clinical diagnosis using observable signs together with a thorough history. These signs include colour, surface changes and texture, and symptoms such as itch and pain. Investigations such as imaging and histology may be needed. Some particular problems are addressed including rapidly enlarging red lesions, firm red lesions, warty lesions, lumps present at or shortly after birth, and malignant tumours.

Dry skin disorders

This chapter on dry skin disorders describes a range of mainly genetic dermatoses whose predominant feature is dry scaly skin. It excludes conditions such as eczema where dry skin is a secondary clinical sign. The underlying mechanism of dry scaly skin is briefly discussed and an algorithm points to possible diagnoses. The focus is on the genetic ichthyoses, defined as congenital, lifelong, generalized dry and scaly skin. The common ichthyoses are non-inflammatory (ichthyosis vulgaris and X-linked recessive ichthyosis) but there are several inflammatory ichthyoses, some associated with fragile skin (blistering) and several with multisystem complications, such as Netherton syndrome. Salient features of each are reviewed with illustrations of selected cases and management is outlined. Two important neonatal presentations, collodion baby and harlequin ichthyosis, are described.

Crusts, scabs, and eschars

Definitions and clinical images are used in this short chapter to permit differentiation between crusts, scabs, and eschars and their likely causes. These are listed as skin infections, trauma, or skin conditions such as eczema or blistering disorders. There are brief descriptions with appropriate treatment and there is cross-referencing to other chapters. Short summaries of diseases causing eschars are provided. These include bacterial infections (e.g. ecthyma, anthrax), viral infections (e.g. cowpox, orf), fungal (e.g. Tinea capitis), and protozoal (e.g. Leishmaniasis) conditions. Also included are skin diseases such as pityriasis lichenoides, toxins/allergens (from various bites and stings), and systemic disease such as autoimmune vasculitis, haematological disorders, or tumours.

Red rashes and erythroderma

Red rashes and erythroderma is the longest chapter in this handbook, covering a huge number of very varied presentations and diseases with cross referral to other chapters. It commences with psoriasis and its variants and then covers most of the red viral exanthems (skin rashes) seen in children (e.g. measles), with succinct clinical descriptions and many images. It goes on to describe infestations (e.g. scabies) and skin infections from fungal causes (e.g. Tinea or ringworm); bacterial (e.g. tuberculosis and leprosy); or spirochaetal (e.g. syphilis and Lyme disease). There are also rare skin diseases described including dietary insufficiency, Kawasaki disease, and mycosis fungoides and systemic diseases such as juvenile idiopathic arthritis. Management of the rare condition erythroderma is described and can be caused by a number of factors including many skin diseases such as psoriasis; infections such as staphylococcal scalded skin syndrome and rarely in children, drugs. Finally, erythroderma, failure to thrive, and recurrent infections are briefly discussed.

Pustular rashes

This chapter describes the common pustular rashes that occur in children. This includes infective causes due to bacteria such as staphylococcus, streptococcus, and pseudomonas, dermatophytic fungi, viruses, parasites, and yeasts. Non-infective causes include primary skin disease such as acne, pustular psoriasis, and neonatal pustular conditions as well as systemic disease and drugs. The chapter lists all the diseases then discusses them according to the body sites that are most commonly affected. A brief clinical summary of each condition is then provided with cross references to other relevant sections of the book.

Endocrine dysfunction and the skin

This chapter describes many of the skin diseases associated with diabetes, thyroid, pituitary, and sex hormone disorders and includes some useful treatment tips and clinical images. Diabetic reactions include skin infections, granuloma annulare, necrobiosis, eruptive xanthomas, and insulin injection site reactions. Brief descriptions of skin problems encountered in hyper- and hypothyroidism are included. The rarer but important skin changes seen in pituitary disorders such as Cushing’s syndrome, Addison’s disease, and acromegaly are described. The role of androgens on the skin and problems created from androgen or oestrogen deficiencies/excess are elaborated. The very rare polyglandular autoimmune type 1 and multiple endocrine neoplasia syndromes are also briefly discussed.

Yellow or orange colouration

This chapter discusses yellow or orange discolouration of the skin, which is uncommon in children. It can occur due to accumulation of carotene in the skin, usually from infant diets containing too much carotene. Rarely, metabolic causes such as chronic renal failure or xanthomas are a cause. Xanthomas are accumulation of lipids or fat in the skin and are usually due to hereditary conditions when it manifests in children. Chronic renal failure makes the skin appear pale and yellowish mainly due to the associated anaemia and sometimes from the accumulation of metabolites in the skin. Naevi (e.g. naevus sebaceous) and rare genetic conditions (e.g. pseudoxanthoma elasticum) may exhibit a yellow/orange colour, as may palmoplantar keratoderma, as seen in some rare genetic disorders.

Blue, grey, and black colouration

Normal ethnic skin colouration is due to melanin in the skin. However, in this short chapter abnormal blue, grey, or black changes in skin colour, both localized or generalized, are discussed and illustrated by a few clinical images. The Mongolian blue spot that occurs as a physiological change in the skin of the majority of Asian, Black, and Chinese infants is due to melanin. It is uncommon in Caucasian skin types and not always recognized. A good illustration of the relatively common blue naevus is provided and much rarer examples discussed such as naevus of Ota, naevus of Ito, and alkaptonuria. In addition to melanin, other chromophores deposited in the skin may appear blue or black, such as haemoglobin or rarely drug deposits. The popularity of tattoos and associated problems are also mentioned.