Wart viruses

A growing recognition that there is an association between human papilloma viruses (HPV), which cause warts, and cancer has led to a renewed interest in these infections. The wart is one of the few tumours in which a virus can be seen to proliferate in the cell nucleus. The different clinical forms of wart are caused by range of HPV, currently divided into over 80 major types. These viruses are also responsible for cervical cancer and have been associated with squamous carcinomas in the...

Systemic treatment

Extensive and inflamed psoriasis that is resistant to local treatment may require systemic treatment. A number of antimetabolite drugs (such as azathioprine and hydroxyurea) and immunosuppressive drugs (such as ciclosporin A) are effective, but the most widely used are methotrexate and acitretin. Methotrexate inhibits folic acid synthesis during the S phase of mitosis and diminishes epidermal turnover in the lesions of psoriasis. Because it is hepatotoxic liver function has to be assessed...

Angiomas

Spider naevi, which show a central blood vessel with radiating branches, are frequently seen in women (especially during pregnancy) and children. If they occur in large numbers, particularly in men, they may indicate liver failure. Palmar erythema and yellow nails may also be present. Eruptive angiomas may be associated with systemic angiomas of the liver, lung, and brain. Port wine stain due to abnormality of the dermal capillaries commonly develops on the head and neck. It may be associated...

Cutaneous leishmaniasis

Cutaneous leishmaniasis is due to the protozoa Leishmania tropica, and is transmitted by the bite of a sandfly. There is a spectrum of disease depending on the patient's immunity. A red nodule like a boil occurs at the site of the bite. It enlarges, may or may not ulcerate, and heals spontaneously after about one year leaving a cribriform scar. In a patient with good cell mediated immunity, after the acute leishmaniasis has healed, new granulomata appear at the edge of the scar these do not...

Localised lesions with epidermal changes

Psoriasis, seborrhoeic dermatitis, atopic eczema, and contact dermatitis can all present with localised lesions. Psoriasis may affect only the flexures, occur as a genital lesion, or affect only the palms. The lack of itching and epidermal changes with a sharp edge help in differentiation from infective or infiltrative lesions. Seborrhoeic dermatitis can occur in the axillae or scalp with no lesions of other areas. In atopic eczema the classical sites in children flexures of the elbows and...

Scabies

The commonest infestation encountered is scabies, and it is easily missed or misdiagnosed. Scabies is due to a small mite, Sarcoptes scabiei. The female mite burrows into the stratum corneum to lay her eggs the male dies after completing his role of fertilisation, and the developing eggs hatch into larvae within a few days. Intense itching occurs some two weeks later, during which time extensive colonisation may have occurred. The infestation is acquired only by close contact with infected...

Treatment of acne

In most adolescents acne clears spontaneously with minimal scarring. Reassurance and explanation along the following lines helps greatly (1) The lesions can be expected to clear in time. (3) The less patients are self conscious and worry about their appearance the less other people will take any notice of their acne. It helps to give a simple regimen to follow, enabling patients to take some positive steps to clear their skin and also an alternative to picking their spots. Patients with acne...

Rashes

A skin rash generally poses more problems in diagnosis than a single, well defined skin lesion such as a wart or tumour. As in all branches of medicine a reasonable diagnosis is more likely to be reached by thinking firstly in terms of broad diagnostic categories rather than specific conditions. There may have been previous episodes because it is a constitutional condition, such as atopic eczema. In the case of contact dermatitis, regular exposure to a causative agent leads to recurrences that...

Descriptive terms

All specialties have their own common terms, and familiarity with a few of those used in dermatology is a great help. The most important are defined below. Derived from the Latin for a stain, the term macule is used to describe changes in colour or consistency without any elevation above the surface of the surrounding skin. There may be an increase of melanin, giving a black or blue colour depending on the depth of the pigment. Loss of melanin leads to a white macule. Vascular dilatation and...

Colour changes

All the nails may be white (leukonychia) due to hypoalbuminaemia in conditions such as cirrhosis of the liver. Brown discoloration is seen in renal failure and the yellow nail syndrome, may be associated with abnormalities of the lymphatic drainage. The nail may have a yellow colour in jaundice. Drugs may cause changes in colour, for example tetracycline may produce yellow nails, antimalarials a blue Dystrophy due to lupus erythematosus Pterygium formation due to lichen planus Dystrophy due to...

Types of acne

Acne vulgaris, the common type of acne, occurs during puberty and affects the comedogenic areas of the face, back, and chest. There may be a familial tendency to acne. Acne vulgaris is slightly more common in boys, 30-40 of whom have acne between the ages of 18 and 19. In girls the peak incidence is between 16 and 18 years. Adult acne is a variant affecting 1 of men and 5 of women aged 40. Acne keloidalis is a type of scarring acne seen on the neck in men. Patients with acne often complain of...

Diffuse hair loss

An interruption of the normal hair cycle leads to generalised hair loss. This may be due to changes in circulating hormones, drugs, inflammatory skin disease, and stress of various types. Telogen effluvium occurs if all the hairs enter into the resting phase together, most commonly after childbirth or severe illness. Two or three months later the new anagen hair displaces the resting telogen hair, resulting in a disconcerting, but temporary, hair loss from the scalp. Stress of any type, such as...

Skin disease involving the scalp

The scalp can be involved in any skin disease, but most commonly in psoriasis and seborrhoeic eczema. A mild degree of scaling from accumulation in skin scales is so common as to be normal (dandruff). Increased accumulation of scales is seen in seborrhoeic dermatitis in which pityrosporum organisms may play a part. Sometimes masses of thick adherent scales develop in pityriasis amiantacea, usually due to psoriasis. Eczema and contact dermatitis can also involve the scalp. Folliculitis decalvans...

Lichen planus

Like psoriasis, the lesions are well defined and raised. They also occur in areas of trauma the Koebner's phenomenon. There is no constant relation to stress. Unlike psoriasis, there is no family history. Itching is common. The distribution is on the flexor aspects of the limbs, particularly the ankles and wrists, rather than on the extensor surfaces, as in psoriasis. It also occurs on the trunk. However, localised forms of lichen planus can occur on the shin, palm, and soles or elsewhere. Nail...

Herpes zoster

Varicella zoster virus (VZV) causes both chickenpox, the primary illness, and herpes zoster, which follows reactivation of the virus in the nerve ganglia. In zoster, pain, fever, and malaise may occur before erythematous papules develop in the area of the affected dermatome most commonly in the thoracic area. Vesicles develop over several days, crusting over as they resolve. Secondary bacterial infection is common. Some patients develop episodes of pain in the affected area postherpetic...

Herpes simplex

The herpes simplex virus consists of two viral subtypes. Type I is associated with lesions on the face and fingers and sometimes genital lesions. Type II is associated almost entirely with genital infections. Recurrent episodes of infection are common, with both due to latent infection of sensory nerve ganglia. Primary herpes simplex (type I) infection usually occurs in or around the mouth, with variable involvement of the face. Lesions are small vesicles which crust over and heal but there may...

Causes of psoriasis

The cause is unknown but there is an inherited predisposition. The strong genetic influence may result from a single dominant gene with poor penetrance or a number of genetic influences. Other factors such as local trauma, general illness and stress are also involved, so the cause of psoriasis is best regarded as being multifactorial. HLA-Cw6 is the phenotype most strongly associated with psoriasis, particularly the early onset variety in which hereditary factors seem to play the greatest part....

Antiseptics and cleaning lotions

Simple antiseptics are very useful for cleaning infected, weeping lesions and leg ulcers. Potassium permanganate can be used by dropping four or five crystals in a litre of water or in an 0-1 solution that is diluted to 0-01 for use as a soak. It will stain the skin temporarily and plastic containers permanently. Silver nitrate 0-25 is a simple, safe antiseptic solution that, applied as a wet compress, is useful for cleaning ulcers. Flamazine (Smith and Nephew) is silver sulfadiazine cream,...

Clinical features widespread blisters

Bullous Pemphigoid Distribution

Chickenpox is so well known in general practice that it is rarely seen in hospital clinics and is sometimes not recognised. The prodromal illness lasts one to two days and is followed by erythematous lesions that rapidly develop vesicles, then pustules, followed by crusts in two to three days. Crops of lesions develop at the same sites usually on the trunk, face, scalp, and limbs. The oral mucosa may be affected. The condition is usually benign. Dermatitis herpetiformis occurs in early and...

Hair loss

This is known as alopecia, said to be derived from the Latin alopex, a fox, presumably because of the bald patches of mange seen in wild foxes. Adult male pattern alopecia is so common as to be considered normal. Circulating levels of testosterone are not Adult pattern of alopecia comparison between men and women raised in bald men but there is evidence that availability of the hormone to the hair follicle is increased. In postmenopausal women there may be widespread thinning of the hair but...

The erythemas

Complex reactions occurring in the capillaries and arterioles of the skin cause erythema, which is simply redness of the skin. This may present as flat macules or as papules, which are raised above the surrounding skin. The lesions may be transient or last for weeks, constant or variable in distribution, with or without vesicles. It is possible to recognise specific patterns within this plethora of clinical signs, but even the most experienced dermatologist may be reduced to making a general...

Urticaria

In this condition itching red weals develop they resemble the effects of stinging nettle (Urtica dioica) on the skin. The condition may be associated with allergic reactions, infection, or physical stimuli, but in most patients no cause can be found. Similar lesions may precede, or be associated with, vasculitis (urticarial vasculitis), pemphigoid, or dermatitis herpetiformis. The histological changes may be very slight but usually there is oedema, vasodilatation, and a cellular infiltrate of...

Specific treatment

(1) Use wet soaks with plain water, normal saline, or aluminium acetate (0 6 ). Potassium permanganate (04 ) solution should be used if there is any sign of infection. Treat the patient, not just the rash Complete cure may not be possible Be realistic about the problems of applying treatments at home Make sure the patient understands how to carry out the treatment Advise using emollients and minimal soap Provide detailed guidance on using steroids (2) Use wet compresses rather than dry...

The itching skin pruritus

It is sometimes very difficult to help a patient with a persistently itching skin, particularly if there is no apparent cause. Pruritus is a general term for itching skin, whatever the reason. Eczema is associated with itching due to the accumulation of fluid between the epidermal cells that are thought to produce stretching of the nerve fibres. As a result of persistent scratching there is often lichenification which conceals the original underlying areas with eczema. Exposure to irritants and...

Insect bites and infestations

So, naturalists observe, a flea Hath smaller fleas that on him prey And these have smaller fleas to bite 'em. And so proceeds Ad infinitum It is, of course, the internal parasites of biting insects that cause trouble for humans, rather than smaller fleas on their surface. An ornithologist went bird watching in Guyana, where he sustained widespread midge bites on the arms. He was referred on account of nodules that developed a few weeks later, then enlarged and ulcerated. Other lesions occurred...

Other benign tumours

A wide variety of tumours may develop from the hair follicle and sebaceous, exocrine sweat , and apocrine glands. The more common include syringomas slowly growing, small, multiple nodules on the face of eccrine gland origin. Naevus sebaceous is warty, well defined, varying in size from a small nodule to one several centimetres in diameter. Lesions occur in the scalp of children, may be present at birth, and gradually increase in size. They may proliferate or develop into a basal cell carcinoma...

Infections

Pseudomembranous Candida

Any type of opportunistic infection is more likely in patients with AIDS and will generally be more severe. An itching, inflammatory folliculitis occurs in many cases. The cause is unknown, but it is possible that Demodex spp. play a part. Superficial fungal infections are often much more extensive and invade more deeply into the dermis than usual. There may also be granuloma formation. Deep fungal infections that are not normally seen in healthy individuals occur in AIDS patients as...

The typical patient

Napkin Psoriasis

Psoriasis usually occurs in early adult life, but the onset can be at any time from infancy to old age, when the appearance is often atypical. The following factors in the history may help in making a diagnosis There may be a family history if one parent has psoriasis 16 of the children will have it, if both parents, the figure is 50 . The onset can occur after any type of stress, including infection, trauma, or childbirth. The lesions may first appear at sites of minor trauma Koebner's...

Mycetoma Madura foot

This is a chronic infection of the dermis and subcutaneous fat caused by various species of fungus eumycetoma or bacteria actinomycetoma . Both types look the same with a swollen foot and multiple discharging sinuses, but it is important to differentiate between them because the treatment is different. Examination of the discharging grains colour will give a clue as to the cause . Culture of the grains to identify the causative fungus or bacteria. If no grains can be found a skin biopsy will...

Tar preparations

These are mainly used for treating psoriasis as described in chapter 3. Tar has an anti-inflammatory effect and seems to suppress the epidermal turnover in lesions of psoriasis. The various tar pastes are generally too messy to use at home and are most suitable for dermatology treatment centres. Standard tar paste contains a strong solution of coal tar 7-5 in 25 g of zinc oxide, 25 g of starch, and 50 g of white soft paraffin. There are numerous proprietary preparations that are less messy and...

Localised alopecia

Alopecia areata is a common form of hair loss. It is seen in 2 of patients attending the average dermatology clinic in the United Kingdom. There may be small patches of hair loss or the whole scalp may be affected. Resolution occurs in a few months or the condition may persist for years. There may be slight inflammation of the skin in the affected areas in keeping with the possibility of an underlying immune reaction against the hair follicles. There is also an association with autoimmue...

Contact dermatitis

The skin normally performs its function as a barrier very effectively. If this is overcome by substances penetrating the epidermis an inflammatory response may occur leading to epidermal damage. These changes may be due to either a an allergic response to a specific substance acting as a sensitiser or b a simple irritant effect. An understanding of the difference between these reactions is helpful in the clinical assessment of contact dermatitis. Common sources of allergic contact dermatitis...

Rosacea

Rosacea is a persistent eruption occurring on the forehead and cheeks. It is more common in women than men. There is erythema with prominent blood vessels. Pustules, papules, and oedema occur. Rhinophyma, with thickened erythematous skin of the nose and enlarged follicles, is a variant. Conjunctivitis and blepharitis may be associated. It is usually made worse by sunlight. Rosacea should be distinguished from Acne, in which there are blackheads, a wider distribution, and improvement with...

Development duration and distribution

Several diseases may present with blisters or pustules. There is no common condition that can be used as a reference point with which less usual lesions can be compared in the same way as rashes can be compared with psoriasis. A different approach is needed for the assessment of blistering or pustular lesions, based on the history and appearance, and is summarised as the three Ds development, duration, and distribution. Was there any preceding systemic illness as in chickenpox, hand, foot, and...

Treatment

Localised lesions of herpes simplex have been treated with a variety of medications from zinc sulphate to iodoxuridine. Topical acyclovir a drug that inhibits herpes virus DNA polymerase is effective but only shortens the duration of illness by a day or so. It is useful in primary infection but should be used as soon as the patient is aware of symptoms. Severe, recurrent, herpes simplex, or herpes zoster can be treated with oral or intravenous aciclovir as early in the course of the illness as...

Seborrhoeic dermatitis

Distribution Pattern Lichen Planus

Seborrhoeic dermatitis has nothing to do with sebum or any other kind of greasiness. There are two distinct types, adult and infantile. The adult type is more common in men and in those with a tendency to scaling and dandruff in the scalp. There are several commonly affected areas Seborrhoeic dermatitis affects the central part of the face, scalp, ears, and eyebrows. There may be an associated blepharitis, giving some red eyes and also otitis externa. The lesions over the sternum sometimes...

Types of eczema

Curing Stasis Dermatitis

The many causes of eczema are not consistently related to the distribution and clinical appearance. In general there are either external factors acting on the skin producing inflammatory changes or it is an endogenous condition. It is important to remember there can be more than one cause for example, in atopic eczema or varicose eczema on the ankle an allergic reaction may develop to the treatments used. Atopic eczema affects mainly the flexor surfaces of the elbows and knees as well as the...

Topical steroids

Topical steroids provide effective anti-inflammatory treatment but have the disadvantage of causing atrophy due to decreased fibrin formation and telangiectasis. They are readily absorbed by thin skin around the eyes and in flexures. On the face the halogenated steroids produce considerable telangiectasia, so nothing stronger than hydrocortisone should be used except in lupus erythematosus . They can cause hirsutism and folliculitis or acne. Infection of the skin may be concealed tinea...

Local treatment

Local treatments entail the use of ointments and pastes, usually containing tar in various forms. It is much easier to apply them in hospital than at home if patients can make the time for hospital visits. Inpatient treatment can be more intensive and closely regulated it also has the advantage of taking the patient completely away from the stresses of the everyday environment. In some units a five day ward enables patients to return home at weekends, which is particularly important for parents...

Early stages

In the early stages 50 of patients have antibiotics to HIV and the p24 antigen can be detected. The proportion of CD4 lymphocytes decreases, and this is associated with the development of secondary changes in the skin. There is also an increase in HIV antibodies so a test for this should be repeated six to eight weeks after the initial illness. Counselling should take place before testing is carried out.

Pityriasis rosea

Guttate Psoriasis Face

The word pityriasis is from the Greek for bran, and the fine bran-like scales on the surface are a characteristic feature. The numerous pale pink oval or round patches can be confused with psoriasis or discoid eczema. The history helps because this condition develops as an acute eruption and the patient can often point to a simple initial lesion the herald patch. There is commonly slight itching. Pityriasis rosea occurs mainly in the second and third decade, often during the winter months....

Scarring alopecia

The absence of hair follicles is an important physical sign as it indicates 1 The presence of an inflammatory process that requires further investigation. 2 That there is unlikely to be any substantial recovery of hair growth. The presence of inflammation does not necessarily produce marked erythema in lichen planus and lupus erythematosus, the inflammatory changes are often chronic. Systemic lupus erythematosus produces areas of inflammation that extend, leaving residual scarring. In discoid...

Incisional biopsy and punch biopsy

Elliptical Surgical Incision

It is essential to have a working clinical diagnosis, but wherever there is doubt the pathologists can provide much more precise information regarding the nature and extent of the lesion. For example, a patch of Bowen's disease intraepidermal carcinoma may resemble sclerosing superficial basal cell carcinoma and a biopsy will usually distinguish them. Similarly, what seems to be a dysplastic pigmented naevus clinically may, on the one hand, prove to be benign or, on the other hand, turn out to...

Hand foot and mouth disease

Hand, foot, and mouth disease Coxsackie virus A affects both children and adults. Incubation period is unknown. Prodromal symptoms. Fever, headache, and malaise may accompany the rash. Initial rash. Initially there may be intense erythema surrounding yellow-grey vesicles 1-1-5 mm in diameter. These are mainly distributed on the palms and soles and in the mouth. Sometimes a more generalised eruption may develop. Development and resolution. Over three to five days the rash fades. Diagnosis....

Seborrhoeic warts

Seborrhoeic warts come in various shapes, sizes, and colours. When deeply pigmented, inflamed, or growing they may appear to have the features of a malignant lesion, but the following features are characteristic Warty, papillary surface often with keratin plugs. Raised above surrounding skin to give a stuck on appearance. Individual lesions vary considerably in size, but are usually 0-5-3-0 cm in diameter. Protuberant and pedunculated lesions occur. Solitary lesions are commonly seen on the...

Tungiasis

Invasion of the skin by sand fleas Tungapenetrans causes tungiasis in tropical areas of Africa, America, and India. It is most common on the feet, especially under the toes and toenails. The condition looks a bit like plantar warts, but if you watch for a while you will see the eggs being squirted out. Carefully winkle the fleas out with a pin most patients know how to do this themselves . If the fleas are very extensive, soak the feet in kerosene or treat with a single dose of ivermectin 200...

Pityriasis lichenoides

Pityriasis lichenoides is a less common condition occurring in acute and chronic forms. The acute form presents with widespread pink papules which itch and form crusts, sometimes with vesicle formation suggestive of chickenpox. There may be ulceration. The lesions may develop in crops and resolve over a matter of weeks. The chronic form presents as reddish brown papules often with a mica-like scale that reveals a smooth, red surface underneath, unlike the bleeding points of psoriasis. In lichen...

What is acne

Acne lesions develop from the sebaceous glands associated with hair follicles on the face, external auditory meatus, back, chest, and anogenital area. Sebaceous glands are also found on the eyelids and mucosa, prepuce and cervix, where they are not associated with hair follicles. The sebaceous gland contains holocrine cells that secrete triglycerides, fatty acids, wax esters, and sterols as sebum. The main changes in acne are thickening of the keratin lining of the sebaceous duct, to produce...

Pityriasis versicolor

Pityriasis versicolor is a skin eruption that usually develops after sun exposure with white macules on the tanned skin but pale brown patches on the covered areas, hence the name versicolor, or variable colour. The lesions are a flat b only partially depigmented areas of vitiligo are totally white and c do not show inflammation or vesicles. The causative organism is a yeast, Pityrosporum orbiculare, that takes advantage of some unknown change in the epidermis and develops a proliferative,...

Molluscum contagiosum

The commonest skin infection due to a pox virus is molluscum contagiosum, a skin infection seen particularly in children. Despite its name it is not very contagious, but can occur in families. In adults florid molluscum contagiosum may be an indication of underlying immunodeficiency, as in AIDS patients. The white, umbilicated papules of molluscum contagiosum are characteristic. Large solitary lesions may cause confusion as can secondarily infected, excoriated lesions. These lesions often itch,...