Skin, nails and hair

Chapter 3 Skin, nails and hair



SYMPTOMS OF SKIN DISEASE


The history should evaluate possible precipitating factors and determine whether the skin problem is localised or a manifestation of systemic illness.




imageQuestions to ask: Skin history



• Was the onset sudden or gradual?

• Is the skin itchy or painful?

• Is there any associated discharge (blood or pus)?

• Where is the problem located?

• Have you recently taken any antibiotics or other drugs?

• Have you used any topical medications?

• Were there any preceding systemic symptoms (fever, sore throat, anorexia, vaginal discharge)?

• Have you travelled abroad recently?

• Were you bitten by insects?

• Any possible exposure to industrial or domestic toxins?

• Any possible contact with sexually transmitted disease or HIV?

• Was there close physical contact with others with skin disorders?


imageDifferential diagnosis: Systemic diseases causing pruritus



• Intrahepatic and extrahepatic biliary obstruction (cholestasis)

• Diabetes mellitus

• Polycythaemia rubra vera

• Chronic renal failure

• Lymphoma (especially Hodgkin’s disease)


Hair thinning


Male-pattern baldness is common; the patient will note the slow onset of hair loss with the hairline receding from the frontal and temporal scalp and crown.




imageQuestions to ask: Hair history



• Was the hair loss sudden or gradual?

• Does the loss occur only on the scalp or is the body hair involved as well?

• Is the baldness localised or general, symmetrical or asymmetrical?

• Is there a family history of baldness (especially in men)?

• What drugs have you taken recently?

• Any recent illnesses, stress or trauma?

• Are there other systemic symptoms (e.g. symptoms of hypothyroidism)?

Patients complaining of localised alopecia (alopecia areata) may have an autoimmune disease. Severe illness and malnutrition, as well as sudden psychological shock, may be associated with hair loss, which usually recovers once the stress has been resolved.



Abnormal hair growth


Failure to develop axillary and pubic hair at the expected time of puberty should alert you to the possibility of pituitary or gonadal dysfunction.




imageDifferential diagnosis: Hirsutism



• Racial variation in hair distribution

• Hormonal imbalance
– polycystic ovaries

– ovarian failure or menopause

– virilising adrenal tumours

• Drugs
– phenytoin

– progestogens

– anabolic steroids

– ciclosporin


imageQuestions to ask: Hirsutism



• Is there a family history of hirsutism?

• Are your menstrual periods normal or absent (or scanty)?

• Is there a history of primary or secondary infertility?

• Do you experience visual disturbances or headaches (pituitary disease)?

• What medications do you take (e.g. phenytoin, anabolic steroids, progestogens)?

Abnormal facial hair growth (hirsutism) is distressing in women. There are racial differences: physiological hirsutism is least apparent in Japanese and Chinese women and most apparent in women of Mediterranean, Middle Eastern, Indian and Negroid extraction.



EXAMINATION OF THE SKIN, NAILS AND HAIR



Examining the skin


Examination relies almost entirely on careful inspection.



ABNORMAL SKIN COLOUR


Changes in skin colour occur in jaundice, iron overload, endocrine disorders and albinism. The yellow tinge of jaundice is best observed in good daylight, appearing as yellowing of the sclerae and then as a yellow discoloration on the trunk, arms and legs.


Iron overload (haemosiderosis and haemochromatosis) causes the skin to turn a slate-grey colour. Addison’s disease is characterised by darkening of the skin, occurring first in the skin creases of the palms and soles, scars and other skin creases. The mucosa of the mouth and gums also becomes pigmented. Striking pigmentation arises after bilateral adrenalectomy for adrenal hyperplasia (Nelson’s syndrome).


Albinism is an autosomal recessive disorder. The skin and hair are white and the eyes are pink because of a lack of pigmentation of the iris (there may also be nystagmus).


Common localised abnormalities of skin pigmentation include vitiligo (Fig. 3.1) and café au lait spots (Fig. 3.2). When examining a patient, you may notice an erythematous flush in the necklace area which is caused by anxiety. Purpura is the term used for red-purplish lesions of the skin caused by seepage of blood from skin blood vessels. These lesions do not blanch with pressure. If the lesions are small (<5 mm) they are called petechiae, whereas larger lesions are purpura.


image

Fig. 3.1 Depigmented skin (vitiligo): white discoloration of brown hand.


image

Fig. 3.2 Café au lait patches in neurofibromatosis.



LOCALISED SKIN LESIONS


Decide whether the lesion is flat, nodular or fluid-filled. Flat circumscribed changes in colour are termed macules if less than 1 cm, or patches if more than 1 cm. If the lesion is raised and can be palpated, assess whether the mass is a papule, plaque, nodule, tumour or wheal. If a circumscribed elevated lesion is fluctuant and fluid-filled, describe whether it is a vesicle, bulla or pustule (Fig. 3.3).


image image

Fig. 3.3 Primary localised skin lesions.


Add to the primary description any secondary characteristics such as superficial erosions, ulceration, crusting, scaling, fissuring, lichenification, atrophy, excoriation, scarring, necrosis or keloid formation.


Compression may be helpful (e.g. demonstration of the characteristic arteriolar dilatation of spider naevi occurring in decompensated liver disease). Inflamed lesions (e.g. cellulitis) are hotter than surrounding tissue, whereas skin overlying a lipoma (subcutaneous fat tumours) is cooler than adjacent tissue.



COMMON SKIN LESIONS



Acne vulgaris


Acne presents with greasy skin, blackheads (comedones), papules, pustules and scars. The disorder affects the face, chest and back. Acne usually subsides in the third decade.



Rosacea


This facial rash usually presents in the fourth decade. Papules and pustules erupt on the forehead, cheeks, bridge of the nose and the chin. The erythematous background highlights the rash (Fig. 3.4). Eye involvement is characterised by grittiness, conjunctivitis and even corneal ulceration.


image

Fig. 3.4 Rosacea: lesions occur on the nose, cheeks and chin.




imageDifferential diagnosis: Skin lesions associated with drug sensitivity



• Toxic erythema

• Exfoliative dermatitis

• Urticaria

• Angioneurotic oedema

• Erythema nodosum

• Erythema multiforme

• Fixed drug reaction

• Photosensitive drug reactions

• Pemphigus


Drug reactions


Drug reactions may occur within minutes or hours of taking the medication but there may also be delays of up to 2 weeks for the reaction to manifest. It is important to recognise different expressions of drug sensitivity.



Toxic erythema


Profuse eruptions affect most of the body. Red macules appear and overlap and coalesce to give the appearance of diffuse erythema. This condition is most often caused by ampicillin but also by sulphonamides (including co-trimoxazole), phenobarbital and infections.



Exfoliative dermatitis


Also known as erythroderma, this dermatitis is characterised by diffuse erythema and desquamation of the epithelium. Barbiturates, sulphonamides, streptomycin and gold are especially implicated.



Urticaria


Urticaria presents with intense itching and localised swellings of the skin that may occur anywhere on the body. Typically, wheals occur that are red at the margins with paler centres.



Erythema nodosum


Symmetrical in distribution, the acute crops of painful, tender, raised red nodules usually affect the extensor surfaces, especially the shins but also the thighs and upper arms (Fig. 3.5). Over 7–10 days, lesions change colour from bright red through shades of purple to a yellowish area of discoloration. Erythema nodosum is caused by vasculitis, and most commonly associated with sulphonamides, oral contraceptives and barbiturates.


image

Fig. 3.5 Erythema nodosum: the nodules are raised and tender.




imageDifferential diagnosis: Erythema nodosum



Infections


• Streptococcal infections

• Tuberculosis

• Leprosy

• Syphilis

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Apr 20, 2017 | Posted by in GENERAL & FAMILY MEDICINE | Comments Off on Skin, nails and hair

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