100 Case Da Liễu. Chẩn đoán Và điều Trị - 123doc

3: An acute monomorphic eruption in a systemically unwell atopic child 5 4: A recurrent, unsightly facial eruption in a stressed but well young adult 7 5: Blistered hands and feet in a

100 CASES

in Dermatology

Rachael Morris-Jones PhD PCME FRCP

Consultant Dermatologist & Honorary Senior Lecturer, King’s College

100 Cases Series Editor:

Professor P John Rees MD FRCP

Dean of Medical Undergraduate Education, King’s College London School

of Medicine at Guy’s, King’s and St Thomas’ Hospitals, London, UK

100 CASES

in Dermatology

338 Euston Road, London NW1 3BH

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© 2011 Rachael Morris-Jones, Ann-Marie Powell and Emma Benton

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3: An acute monomorphic eruption in a systemically unwell atopic child 5

4: A recurrent, unsightly facial eruption in a stressed but well young adult 7

5: Blistered hands and feet in an athletic man 9

6: Chronic erythematous pruritic eruption on the lower legs 11

8: An eczematous eruption complicating venous ulcers 16

9: A transient pruritic eruption exacerbated by heat 19

10: A toddler with brown patches which urticate 23

11: Acute soft tissue swelling associated with systemic symptoms 25

13: Widespread scaly eruption appears after a sore throat 29

14: A patient presents acutely unwell with all his skin red and hot 31

15: An itchy eruption appearing on the chest and arms after sun exposure 33

16: Acute-onset linear blistering on the legs 35

17: Chronic blistering eruption on the dorsal hands 37

18: Sun-induced skin pain, redness and scarring in a child 39

20: Recurrent annular erythematous lesions reactivating

21: Painful lip lesion associated with a localized

22: Painful eroded mucous membranes and skin lesions 47

23: Acute-onset extensive blistering and skin necrosis with

24: Fever, epilepsy and a widespread skin eruption

25: Acute-onset multiple pustules on a background of erythematous skin 53

26: Acute non-blanching cutaneous eruption associated with a sore throat 55

28: A generalized itchy blistering eruption in an elderly woman 59

29: Sudden onset of erosions, blisters and fragile skin

following gradually worsening mouth ulcers 63

30: An itchy, vesicular extensor eruption associated with malabsorption 65

31: An itchy blistering eruption recurring in a second pregnancy 67

32: Extremely itchy stretch marks in the third trimester 69

33: Asymptomatic sclerotic white plaques on the trunk 71

34: Insidious onset of tightening of the skin over the limbs 73

35: Acute facial rash, fever and joint pains in a young woman 75

36: Annular erythematous rash of sudden onset 79

37: Hair loss, scarring rash and photosensitivity 81

38: An erythematous rash and muscle weakness 83

39: Widespread maculopapular eruption on the trunk and

40: Slow asymptomatic depigmentation of the skin 87

41: A young adult with high blood pressure,

42: An overweight teenager with thickened skin around her neck 93

43: A dramatic and painful ulcer in a young patient

44: Slow-onset asymptomatic lesions on the shins of a diabetic patient 97

45: Slowly progressive swelling and discolouration over the shins 99

46: Asymptomatic annular lesions on the limbs 101

47: An asymptomatic papular and annular eruption 103

48: Ulcer over the gaiter area on a background of aching legs 105

49: Slow-onset, unilateral, painless leg swelling 107

50: An infirm elderly man with arterial disease and an ulcerated heel 111

51: Non-healing foot ulcer in a diabetic patient 113

52: A regressing vascular lesion in a pre-school child 117

53: A livid red birthmark on a newborn child 120

54: Slow development of a scaly plaque on a finger 123

55: A slow-growing ulcerated non-healing nodule on the face 125

56: Multiple basal cell carcinomas in a young patient 127

57: An ulcerating lesion on the scalp, enlarging over 4 months 129

58: A rapidly growing lesion on the dorsum of the hand 131

59: A longstanding flesh-coloured nodule on the face 133

60: Multiple, slightly atypical looking naevi on the trunk 137

61: An enlarging pigmented macule on the face of an elderly man 139

65: Longstanding erythematous scaly patches 147

66: A slow-growing plum-coloured skin nodule 149

67: Papular and pustular eruption on the face with scarring 151

69: Sudden-onset facial crusting and blistering in a child 155

72: Painful areas of superficially eroded skin in the flexures of a child 161

82: Asymptomatic purple skin lesions appearing on the limbs and trunk 181

83: Widespread itchy eruption preventing sleep 183

84: Painless erythematous lesion on the nose grows over four months 185

85: Scaling of the scalp with occipital lymphadenopathy in a child 187

86: A pruritic annular rash and family involvement 189

87: Progressive scaling of the palms and dystrophy of the fingernails 193

88: Patchy asymptomatic hair loss over the scalp 195

90: Excessive facial hair in a young woman 199

91: Multiple skin lesions develop in a renal transplant recipient 201

92: Stiffness of the skin developing after bone marrow transplantation 203

93: Streaky skin changes in a toddler and a maternal history

94: A young adult with seizures and markedly photo-damaged skin 207

95: A young man seeking genetic counselling advice regarding

96: Recurrent blisters on the extremities associated with

97: An increasing number of asymptomatic facial lesions in a young boy 213

98: Macroglossia, fatigue and back pain in an elderly woman 217

99: Subacute pruritic erythematous eruption in an elderly

100: A young girl with unusual scars and unexplained injuries 223

a picture is worth a thousand words; therefore, we hope that the clinical photographs accompanying each case will speak for themselves in many more words than we would ever be permitted to write.

Rachael Morris-JonesAnn-Marie PowellEmma Benton

The authors are indebted to all the patients who kindly allowed us to include their tures in this book to illustrate the clinical signs We would also like to sincerely thank the Medical Photography Departments in the St John’s Institute of Dermatology, Guy’s and

pic-St Thomas’ Hospital NHS Trust and King’s College Hospital NHS Trust for taking such excellent quality clinical images; and for the crucial role this plays in patient care and supporting ongoing Medical Education

Abscess: deep collection of pus caused by a skin infection

Angioedema: temporary, rapid swelling of the skin

Annular: ring-shaped lesion

Atrophy: loss of tissue density

Bulla (-ae): large, fluid-filled blister(s) greater than 0.5 cm

Crust: dried skin fluid

Cyst: distinctive, closed sac-like structure in the skin, usually fluid with a semi-solid substance Dermographism: ‘writing on the skin’, red, raised and inflamed skin due to firm stroking Desquamation: peeling of superficial scales

Ecchymoses: bruise; a collection of blood in the skin

Emollient: moisturizer to soften and soothe the skin

Eroded: superficial loss of the epidermis

Excoriations: scratch marks causing partial/complete loss of the epidermis

Fissures: slits through the whole thickness of the skin

Fitzpatrick skin type: numerical classification of skin colour from type I (white) to type VI (black) Fomites: inanimate object able to carry and hence transfer infectious particles

Furuncles: deep boil (skin infection) affecting the entire hair follicle

HAART: highly active antiretroviral therapy

Hyperkeratosis: thickening of the epidermis (stratum corneum)

Hypertrichosis: hair growth perceived to be excessive on the skin

Induration: hardening of the skin (e.g due to inflammation, accumulation of fluid or

tumour cells)

Koebner’s phenomenon: skin lesions appearing in the lines of trauma

Lentigines: small area of increased pigmentation of the skin

Lichenification: thickening of the skin with prominent skin markings

Maceration: continually wet skin turns soft and white

Macule: change in the pigmentation of the skin (colour change) without any elevation

(non-palpable)

Nikolsky’s sign: sloughing-off of the epidermis from the dermis caused by lateral pressure Nodule: circumscribed raised lesion greater than 1.0 cm in diameter

Oedema: fluid (in the skin)

Onycholysis: lifting/separation of the nail plate off the nail bed

Papule: circumscribed raised lesion of 0.5-1.0 cm in diameter

Pedunculated: lesion/mass supported on a stalk

Plaque: circumscribed elevated plateau area, usually greater than 1 cm in diameter Pruritus: itching (a sensation you feel)

Purpura: purple non-blanching colour in the skin, usually due to damaged vasculature Stomatitis: inflammation of the mucous lining of the oral cavity

Telangiectasia: small, dilated blood vessels near the skin/mucosal surface

Ulceration: results from loss of the entire epidermis and dermis

Vesicles: fluid-filled lesions (blister – usually clear fluid, may be haemorrhagic)

CASE 1: AN ITCHY , SLOW - GROWING INFANT

History

A 26-week-old baby boy attends your clinic with his mother He has developed a eralized dry, red, itchy rash over the past seven weeks His mother has been applying a regular emollient diligently and using a bath emollient She reports that he is waking more and more frequently at night and appears to be troubled by his skin She is worried about weaning him He is currently breast-fed and his mother has an unrestricted diet

gen-He has been offered a bottle of formula milk, but took only 60 mL before vomiting and developing a rash He also developed a rash when his father kissed him, immediately after eating an egg mayonnaise sandwich

He is the first baby of his parents; his mother had asthma in childhood and his father is allergic to shellfish There are no pets at home His father is a smoker The baby was born

at term by normal vaginal delivery and is vaccinated to date

Examination

His height has reached a plateau over the past eight weeks and now rests on the 9th centile for his age He is alert and happy, although he rubs his legs vigorously when undressed He has generally dry skin, with widespread low-grade erythema and raised, poorly defined patches of active eczema; there are widespread excoriations (Fig 1.1) and

no clinical evidence of impetiginization He has low-grade generalized shotty enopathy The rest of his examination is normal

lymphad-Skin prick tests

Cow’s milk protein 8 mm Highly likely to be allergic

INVESTIGATIONS

Questions

• What is this eruption?

• What associated condition does he sent with?

pre-• What dietary recommendations will you make for the baby (and mother)?

Figure 1.1

This eruption is eczema The history his mother gives makes an associated food allergy probable – likely to egg and cow’s milk protein (CMP) This, in combination with a posi-tive family history of food allergy and asthma, means we can classify his skin condition

as atopic eczema His mother is correct to be anxious about weaning him

It would be appropriate for this baby to be investigated for associated food allergy Food allergy is more likely in babies presenting with eczema from a young age, and it is pos-sible that food allergy may be contributing to the activity of his eczema and vice versa The first line investigation should be skin prick test (SPT) to the common weaning food protein allergens (CMP, egg, soya, wheat, and fish) Peanut is commonly added to this initial panel

The history suggests that this baby is likely to be allergic to egg and CMP, and this has been confirmed by SPT It would be worth restricting his mother’s intake of these proteins if she intends to continue breast-feeding as this may improve eczema control

If his mother wishes to stop breast-feeding, the most appropriate alternative at his age would be an amino acid formula The incidence of coexisting CMP and soya allergy is high and the positive SPT would suggest this baby is currently allergic to both CMP and egg are nutritionally important and ensuring a balanced diet while restricting both can

be challenging; specialist dietetic advice is important Low-grade exposure to allergenic proteins through maternal milk might be contributing to skin signs and his static growth parameters

Regular use of topical emollients and avoidance of detergents are essential for taining the skin barrier function of infants with eczema It is unlikely, however, that emollients and dietary restriction alone will suffice in the management of his eczema His parents should be introduced to the practical aspects of topical therapy and a ‘step-

main-up, step-down’ approach to the management of flares They should be taught to identify flares early and initiate effective therapy quickly

The association of early-onset eczema and egg allergy is associated with a three-fold increased risk of asthma in later childhood This is an important opportunity to discuss the potential contribution paternal smoking would have on increasing that risk Reassuringly, both egg and CMP allergy are frequently outgrown, although peanut allergy is more likely

to persist

KEY POINTS

• Atopic eczema frequently presents within the first year of life and early onset is associated with risk of associated food allergy

CASE 2: AN AGITATED ATOPIC CHILD

History

A 5-year-old girl who is well known to your practice attends with her mother She has been troubled by worsening pruritus over the last six weeks She has missed more than ten days of school in the last month Her mother reports that she wakes frequently at night and is lethar-gic and moody during the day Her bed sheets are covered in flecks of blood in the morning The girl is known to be allergic to egg, fish and peanut, and has begun to develop the symptoms of seasonal allergic rhinoconjunctivitis within the last couple of months She has

a positive family history of atopy, both parents are allergic to animals and her older brother has asthma Her younger brother has been sent home from nursery with impetigo recently.Her treatments include an emollient as soap and leave-on preparation and various strengths of topical steroids ranging from very mild to moderately potent depending on site and eczema severity On questioning, however, mother

reports that her daughter’s skin is so sore that she is refusing

to bathe or apply her topical treatment

Examination

A full examination reveals a fractious child; she is unable to

stop scratching her skin once undressed She is slim, with her

height at the 25th centile and weight at the 4th centile for

her age She has widespread, mildly tender, shotty

lymphad-enopathy (cervical, axillary and groin) Her skin is generally

mildly erythrodermic and extensively excoriated, particularly

her limbs (Fig 2.1), neck and lower back The excoriations

are covered with haemorrhagic crust and yellowish exudates

Questions

• What is the primary diagnosis?

• What secondary complications are exacerbating her pruritus?

• How would you manage this patient?

INVESTIGATIONS

Normal

White cell count 13.7 109/L 3.9–10.6  109/L

Figure 2.1

The primary diagnosis is atopic eczema associated with a positive family history of atopy

as well as manifestations of IgE-mediated (immediate-type) hypersensitivity (food allergy and allergic rhinoconjunctivitis) This is clearly a moderate to severe flare of her eczema The severity of eczema can be ‘scored’ by various validated subjective (e.g CDLQI – chil-dren’s dermatology life quality index) and objective scoring systems Crudely, however, the impact on sleep and school attendance as well as the clinical severity of her eczema demonstrated in the photograph denotes severe eczema with significant functional disruption

There may be several factors contributing to the current flare It is likely that there is an

element of secondary infection with Staphylococcus aureus or impetiginization of this

child’s eczema The extensive yellow crusting of her excoriations, her tender enopathy, and the fact that her brother has impetigo, suggest colonization of the patient and potentially other family members Difficulty in adhering to a bathing regime is likely

lymphad-to contribute Other potential faclymphad-tors which worsen pruritus include iron deficiency She

is also vitamin D deficient, presumably due to her dietary restriction (egg and fish are the main dietary sources of vitamin D)

It is important to gain control of this child’s eczema rapidly Swabs should be taken for microbiology culture and sensitivity testing both from the patient and her immediate family members As there appear to be at least two members of the family affected by

Staphylococcus aureus it would be worthwhile considering Staphylococcus eradication

protocol for the entire family (i.e antiseptic washes and antibacterial nasal ointment)

The patient might benefit from a 5–10-day course of antibiotic with good Staphylococcus aureus coverage (first line: flucloxacillin; second line: erythromycin or co-amoxiclav)

The extensive use of a moderately potent topical corticosteroid ointment for 2–4 weeks may be required before weaning back to weak preparations or calcineurin inhibitors as maintenance therapy

KEY POINTS

• Atopic eczema is by definition eczema associated with a personal and/or family history

of atopy

• Staphylococcus aureus may cause severe flare of eczema.

• Management of such a flare includes Staphylococcus aureus eradication as well as

appropriate treatment of the eczema

CASE 3: AN ACUTE MONOMORPHIC ERUPTION IN A

SYSTEMICALLY UNWELL ATOPIC CHILDHistory

A 6-year-old boy is brought to the accident and emergency department by his parents with a 5-day history of worsening eczema associated with malaise and lethargy In addi-tion to worsening pruritus and sleeplessness he complains of painful skin, particularly around his face, neck, chest and forearms He quantifies the level of pain as 8 out of 10 His current flare is not responding to diligent application of his usual eczema treatments according to his ‘step-up’ management plan

The onset of his eczema was at the age of 4 months, and although moderately severe

in infancy it has been reasonably controlled since starting primary school, with regular use of emollients and mild to moderately potent topical steroids His background his-tory includes egg allergy (now partially outgrown in that he tolerates well cooked egg in cakes) and asthma, currently stable He has never been admitted to hospital before He

is fully vaccinated to date and had chickenpox at the age of 4 years His father suffers from hay-fever and experienced childhood eczema and asthma He has one older sister (aged 14) who is well

His medication includes:

• Regular emollients both as leave-on preparations and soap substitute

• Topical tacrolimus 0.1% twice daily applied to affected areas for the management of flares

• Hydroxyzine 10 mg nocte during flares and salbutamol inhaler on a prn basis

Examination

He looks unwell and is febrile at 38.5 °C Systemic examination is normal except for widespread lymphadenopathy There is no evidence of conjunctival erythema and his vision is normal He has generalized moderate to severe eczema with erythema, dryness, excoriation and lichenification He has a superimposed monomorphic eruption over his lower face, chest and forearms The eruption is composed of multiple 23-mm monomor-phic ‘punched-out’ erythematous lesions in various stages of evolution (Fig 3.1) Some of the lesions are vesicular, others pustular, some coalescing, most are eroded and covered with a golden exudate and others haemorrhagic crust

Questions

• What are these lesions?

• How would you confirm the diagnosis?

• What complications can be associated with them?

• What is their management?

Figure 3.1

These are typical lesions of herpes simplex virus (HSV) infection complicating atopic eczema This eruption is called eczema herpeticum, or less commonly Kaposi’s varicel-liform eruption

Diagnosis can be confirmed by viral swab of a blister or eroded area Many tests can detect HSV within tissue or blister fluid HSV can be inferred by positive staining or electron microscopy or specifically identified as types HSV-1 or HSV-2 by immunofluo-rescence, culture, or polymerase chain reaction Bacteriology swab for microscopy and culture should also be undertaken

Significant morbidity is associated with eczema herpeticum The main potential plications include superimposed bacterial infection (Staphylococcus or Streptococcus) with risk of systemic sepsis, ocular involvement (in particular, HSV keratitis) and, rarely, systemic HSV infection with risk of spread to the liver, the lungs, the brain, the gastroin-testinal tract and even the adrenal glands In addition pain and discomfort associated with eczema herpeticum is significant

com-The management of widespread eczema herpeticum includes systemic treatment of HSV infection with aciclovir, identification and treatment of any superimposed bacterial infection or strategies to prevent superimposed infection, such as antibacterial washes and creams Topical tacrolimus should be discontinued in this patient as this may exac-erbate the cutaneous spread of HSV These cases are usually managed as in-patients, initially with intravenous aciclovir – as oral preparations can be poorly absorbed Ophthamological review should be sought in cases of diffuse facial herpes simplex infec-tion or where conjunctival/corneal involvement is suspected

In a minority of cases recurrences can occur Rapid treatment of incipient lesions with topical aciclovir may help prevent disseminated eczema herpeticum

CASE 4: A RECURRENT , UNSIGHTLY FACIAL ERUPTION IN A

STRESSED BUT WELL YOUNG ADULTHistory

A 29-year-old man attends your clinic with a 4-year history of a recurrent and itchy facial eruption that he feels is unsightly He notices the eruption is worse in the winter and tends to improve over the summer He is currently studying for business exams and feels the associated stress has triggered the current flare He avoids soaps, which make his face sore, and recently has reduced his alcohol intake in an effort to improve his eruption

He is otherwise well and on no medication

Examination

A full examination is unremarkable except for the skin of his face, neck, central chest and scalp There are poorly defined erythematous patches with overlying adherent greasy scale affecting his naso-labial folds and extending onto his cheeks (Fig 4.1) His eyebrows, scalp, nape of his neck and central chest are similarly affected

Figure 4.1

Questions

• What is this eruption?

• What age groups are affected?

• How would you manage this patient?

This eruption is seborrhoeic dermatitis It is more common among men and typically affects the sebum-rich areas of the face, scalp and chest The pathophysiology of sebor-

rhoeic dermatitis is incompletely understood, however It is linked with Malassezia yeast,

complement activation and abnormalities of T-cell immunity It may worsen in als infected with HIV or affected by Parkinson’s disease

individu-The condition usually begins around puberty with a peak of incidence between 25 and

40 years of age An infantile form of seborrhoeic dermatitis may manifest as cradle cap (Fig 4.2), facial greasy scaly dermatitis, napkin dermatitis and, rarely, as an erythroderma

In predisposed individuals seborrhoeic dermatitis usually recurs Treatment is aimed, therefore, at reducing morbidity and preventing flares Treatment aims are two-fold: reducing the yeast burden as a secondary preventative measure, and switching off the resultant secondary dermatitis when it occurs Although topical corticosteroids may improve appearances of the dermatitis in the short term, they are thought to hasten recur-rences and may foster dependence due to a ‘rebound effect’ and are usually discouraged The use of a ketoconazole shampoo, with frequent washing and prolonged lathering often improves associated dandruff and may improve the facial involvement by depletion of

Malassezia Use of ketoconazole shampoo as a face wash can be irritating, but if

toler-ated may improve erythema and scaling Ketoconazole or miconazole cream, calcineurin inhibitors in combination with antiseptic emollient washes are recommended For severe

or refractory seborrhoeic dermatitis systemic itraconazole as a short course or ‘pulsed’ (one week per month) is highly effective at reducing the yeast burden

Figure 4.2

KEY POINTS

• Seborrhoeic dermatitis is characterized by poorly defined erythematous patches with

CASE 5: BLISTERED HANDS AND FEET IN AN ATHLETIC MAN

Examination

He has diffuse vesicles, coalescing to form tense bullae over the palmar aspects of both hands extending into the interdigital spaces (Fig 5.1) and onto the dorsa of his fingers and hand In addition he has erythema, maceration, fissuring and peeling between the 4th and 5th toes on the left side and bilateral but asymmetrical (left worse than right) purulent vesicles over the insteps

Questions

• What is the diagnosis?

• What investigations would you perform?

• What treatments would you initiate?

Figure 5.1

The diagnosis is pompholyx or dyshidrotic eczema, the symmetrical and diffuse clear icles over the palmar aspect of the hands associated with pruritus are highly suggestive and the diagnosis is based on clinical features Other differential diagnoses to consider include contact dermatitis (irritant or allergic), friction blisters (e.g epidermolysis bullosa simplex), herpes simplex infection, and palmoplantar pustular psoriasis

ves-Atopy appears to be a predisposing factor for pompholyx There are several potential triggers of pompholyx including stress and as an ‘id reaction’ to a distant dermatophyte infection In this case the features of interdigital maceration associated with inflamma-tory pustules and vesicles on the instep are suggestive of inflammatory tinea pedis Investigations should include scrapings from the feet (interdigital spaces and affected areas over the plantar aspects) and hands for mycological tests (direct microscopy and culture) In this case, scrapings from the feet demonstrated hyphae and spores on direct microscopy with subsequent culture confirming the presence of the zoophilic organism

Trichophyton mentagrophytes var mentagrophytes There was no fungal infection of the

hands

Treatment of a pompholyx ‘id reaction’ involves treatment of the tinea pedis as well as treatment of the pompholyx itself Inflammatory tinea pedis is usually managed with sys-temic antifungal therapy (itraconzole, terbinafine or fluconazole) Infected scales can be present on clothing or within footwear, so frequent laundering is recommended Draining the larger bullae with a sterile needle will reduce the discomfort Compresses or soaks with dilute potassium permanganate help to dry the vesicles and prevent secondary bac-terial infection Potent or superpotent topical corticosteroids are the mainstay of therapy

In the short term a combination preparation of topical corticosteroids and antibacterial agent is useful Occasionally, systemic steroids are required

KEY POINTS

• Pompholyx occurs as a manifestation of hand eczema, irritant or allergic dermatitis and

as an ‘id reaction’ to a distant dermatophyte infection

• The mainstay of treatment is the prevention of secondary infection and use of potent or superpotent topical corticosteroids as well as identification and eradication of the trigger

CASE 6: CHRONIC ERYTHEMATOUS PRURITIC ERUPTION ON

THE LOWER LEGSHistory

A 67-year-old woman presents to the vascular surgeons with varicose veins She had a history of venous ulceration in the past, which has now healed and she is being consid-ered for bilateral varicose vein surgery At the consultation she complained of a 3-month history of skin itching and redness, particularly on the right lower leg, and was noted to have unilateral erythema and was referred to dermatology for an opinion

Examination

This patient has obvious dilated and tortuous veins on both lower legs Confluent ground dull erythema is seen on the right lower leg, with small inflammatory superficial erythematous erosions and excoriations (Fig 6.1) Palpation revealed warm, dry, rough skin at the affected site

back-Vascular studies

Resting pressure right: 174 mmHg, left: 180 mmHg, brachial: 167 mmHg

Resting ankle/brachial pressure index right: 1.042, left: 1.078 Bilateral triphasic pulsatile

waveforms

Venous studies showed bilateral saphenofemoral reflux

INVESTIGATIONS

Questions

• What is the diagnosis?

• What treatment would you recommend for her right leg prior to vein surgery?

• Is this patient suitable for compression hosiery based on the vascular studies?

Figure 6.1

This patient has chronic cutaneous changes seen on the right lower leg consistent with the diagnosis of varicose eczema This common cutaneous eruption usually has an insidi-ous onset over many weeks to months in patients with a background of venous incompe-tence The affected skin is pruritic and dry with marked erythema which may be variable

in intensity depending on its chronicity In the context of venous insufficiency, pitting oedema may develop owing to poor venous return leaving the skin tight and oedema-tous This results in reduced blood flow to the skin, leading to active dusky erythema and resultant erosions or even ulceration

Varicose eczema can be readily distinguished from cellulitis affecting the lower leg Varicose eczema usually develops slowly, is frequently bilateral, pruritus is marked, the skin surface is rough and dry, and there are associated varicose veins Frequently there is

a background brown discolouration of the affected skin area due to haemosiderin tion Haemosiderin pigment is derived from haemoglobin, which is left behind in the skin when red blood cells extravasate into the tissue

deposi-Management of the skin requires a combination of topical therapy and if possible pression The leg should be washed with aqueous cream or an antiseptic emollient such

com-as Dermol 500® A moderately potent topical steroid should be applied to the eczematous areas and a rich bland emollient Compression hosiery or two to four layer bandaging is essential to ‘squeeze’ the fluid out of the legs and allow skin healing If the ankle/brachial pressure index (APBI) is above 0.8 then the arteries are sufficiently patent to permit compression without compromising the arterial blood supply to the lower extremities

CASE 7: AN ITCHY LOCALIZED ERUPTION

History

A 59-year-old bus driver presents with a 5-month history of a persistent itchy patch below his umbilicus Initially it began as an intermittent eruption, coming and going in

an apparently random pattern; over the past six weeks, since the weather became warmer,

it has persisted He is otherwise well with no history of previous skin problems He is not

on medication

Examination

There is a localized area of marked lichenification, post-inflammatory tion, excoriation and erosion at the midline below his umbilicus (Fig 7.1) The surround-ing skin has a more diffuse area of low-grade lichenification, hyperpigmentation and mild erythema

hyperpigmenta-Questions

• What could this eruption be?

• How should he be investigated?

• What information does this man need?

Figure 7.1

These lesions are best described as chronic and eczematous Such a localized problem suggests an exogenous aetiology (the photograph that is Fig 7.1 provides a clue) The most likely diagnosis is allergic contact dermatitis (ACD), although it can be very diffi-cult to differentiate clinically between ACD and irritant contact dermatitis Occasionally, psoriasis may present with a single plaque, particularly at a site of trauma (Koebner’s effect); however, it is rarely as pruritic as this eruption Atopic dermatitis is usually

a more generalized and diffuse eruption; however discoid or nummular eczema is characterized by fairly well defined, coin-shaped, intensely pruritic inflamed areas of lichenified skin An inflammatory tinea corporis particularly associated with a zoophilic organism might also be considered The presentation of contact dermatitis can be varied, including dyspigmentation, pustular lesions, urticaria, atrophy, phototoxic reactions and eczema

It would be appropriate to obtain a skin scraping for mycology investigations Patch testing (Fig 7.2) is the diagnostic test to detect sensitization to contact allergens (Although patch testing is not required for diagnosis; nickel allergy is one of the few types of allergic contact dermatitis where the history of exposure along with the signs and symptoms are quite distinctive.) In fact many patients do not present

to medical practitioners as they may well work out the association themselves If a patch test series confirms the presence of nickel allergy, its relevance to the current eruption should be confirmed A dimethylglyoxime (DMG) test is a simple, inexpen-sive way to determine whether the object in question contains nickel by a pink colour change Chromate, palladium and cobalt are commonly found together with nickel and concomitant allergy may coexist

Nickel is a leading cause of allergic contact dermatitis and is responsible for more cases than all other metals combined Certain occupations with high exposure to nickel, such

as cashiers, hairdressers, metal workers, domestic cleaners, food handlers, bar ers, and painters, are also at risk for acquiring nickel dermatitis Patients with atopic eczema are also at increased risk Sweating may increase the severity of the dermati-tis Sodium chloride in the sweat causes corrosion of the metal and increases nickel exposure

work-The management of this case includes removal of the offending nickel-containing belt buckle or trouser rivet and application of topical corticosteroid creams until the erup-tion has resolved The patient also requires information about his allergy, that is he will always remain allergic to nickel and to both the common and unexpected sources of nickel Nickel allergy is commonly associated with earrings and jewellery or other body piercing Nickel can be found in many everyday items – from coins to necklace clasps,

Day 1 Detailed history: Questions focus on exposures at home and

work Understand work environment Better or worse on holidays? List of all personal care products Hobbies and past-times

Choice of patch test series: The European Standard Battery

(25 most common contact allergens) will identify ~80% of contact allergens Commonly specific extended series performed according to likely exposure (e.g healthcare series)

Application of patch tests: Allergens applied within Finn

chambers directly to upper back Secured with adhesive tape.Day 3 (after 48 h) First reading: Patient returns Inspect patches (ensure adequate

adhesion) Mark individual sites Score any positive reactions (/, 1 to 3 or irritant)

Day 5 (after 72 h) Second reading: Score any positive reactions (as above) Interpret

the results Review exposure and product constituents Patient information: once identified, patients are provided with written information sheets about any allergens to which they reacted

Patch testing (Fig 7.2)

!

Figure 7.2 This shows an example

of patch testing in a different patient The erythematous areas over the upper back demonstrate positive eczematous reactions at day 5 of patch testing

KEY POINTS

• Nickel is the most common allergen detected in patch test clinics worldwide It is a

strong silver-coloured metal that is commonly used in buckles, utensils and coins

It should no longer be present in jewellery purchased within the European Union

• A useful test to confirm whether a particular item contains nickel is the

dimethylglyoxime (DMG) test

• The management includes treatment of the manifestation and avoidance of direct

cutaneous contact with nickel

You are asked to review a 72-year-old retired hairdresser, who attends the leg-ulcer clinic because of a 4-week history of progressive worsening pruritus of her right lower leg Prior to this she had a venous ulcer over the medial malleolus of her right leg, which has gradually healed over a 4-month period with the diligent application of three-layer compression bandaging by her local nursing team Her treatment regime includes a wash with chlorhexidine containing emollient lotion, application of paraffin emollient to the entire lower leg, followed by betamethasone–neomycin ointment applied directly to areas

of stasis eczema and easy-release gauze over the ulcerated area The three-layer bandages are changed twice weekly Skin swabs have been taken over the past couple of weeks because of the worsening skin rash

She is otherwise well Her only oral medication is bendroflumethiazide 2.5 mg daily for hypertension

Examination

Physical examination reveals a large but localized area of intense erythema and skin swelling confined to the anterior, posterior and medial aspect of her right lower leg (Fig 8.1) There is marked exudate with suggestion of surface vesiculation No involve-ment of her skin above her knee or foot is apparent Although her skin is sore and itchy there is no swelling or tenderness of her calf She has no palpable lymphadenopathy The rest of her examination including peripheral arterial examination was normal

Skin swab (4 and 12 days ago – identical reports) No growth

INVESTIGATIONS

Questions

• What is likely to have caused the acute deterioration?

• How would you investigate this patient?

• What advice will you give the patient?

With acute erythema and swelling of the leg one of the most important differential diagnoses to consider would be a deep venous thrombosis (DVT) However DVTs are not associated with the significant degree of epidermal change seen in this case, particularly

in the absence of any other suggestive features (such as swelling or intramuscular ness) The negative skin swab does not rule out cellulitis; the morphology and distribution

tender-of the eruption would, however, be atypical and the absence tender-of raised white cell count or inflammatory markers effectively rules it out

The clinical features in this case are highly suggestive of dermatitis (stasis, irritant or allergic contact dermatitis) The extensive involvement and vesiculation would be unu-sual for stasis dermatitis, which is usually confined to the ‘gaiter’ area, particularly above the medial malleolus

The most appropriate investigation would be patch testing Individuals with stasis titis and stasis ulcers are at high risk for developing allergic contact dermatitis to topical medications applied to inflamed or ulcerated skin Patients may also develop allergies to constituents of the bandages and dressings applied The chronicity of this condition and the frequent occlusion of applied medications in these patients contribute to the high risk of allergic contact dermatitis to preservatives in medications and/or to the active ingredients

derma-in topical medications Although neomycderma-in penetrates derma-intact skderma-in poorly, it is an important cause of allergic contact dermatitis when applied to patients with venous stasis/ulceration It

is used surprisingly frequently despite the lack of documentation of its efficacy in the ment of stasis ulcers (Its poor penetration may explain the fact that a positive patch test reaction to neomycin may be delayed for four days or later following initial application.)Individuals may develop widespread dermatitis from topical medications applied to leg ulcers or from cross-reacting systemic medications administered intravenously Neomycin

treat-is also commonly found in combination preparations with other antibacterials and steroids These prescription and non-prescription preparations are used to treat a variety of skin, eye and external ear disorders that have become infected and inflamed Neomycin is also present as a preservative in some vaccine preparations It should be assumed that indi-viduals allergic to neomycin are allergic to chemically related aminoglycoside antibiotics (e.g gentamicin, tobramycin) and these agents should be avoided (topically or systemically)

Following their resolution the lesions leave no persistent skin change Although the eruption is pruritic there is no evidence of lichenification or excoriations Her blood pressure is 105/68 mmHg and pulse rate 102 beats/min Examination of her cardiorespiratory system is otherwise normal Her abdomen is soft and non-tender You notice

a degree of bilateral upper eyelid lag She has

a smoothly enlarged goitre and stretching her hands out she has a fine tremor

Examination of the remainder of the cal system is normal Urinalysis was negative for blood, white cells and glucose You ask the patient

neurologi-to put on her coat and walk briskly up and down the corridor outside After five minutes she returns with a marked aggravation of her eruption, which

is now widespread and generalized over her trunk and proximal limbs You draw around a well-defined skin lesion and request some further investigations

CASE 9: A TRANSIENT PRURITIC ERUPTION EXACERBATED BY HEATHistory

A 26-year-old woman attends the dermatology clinic complaining of a 4-month history of

an itchy eruption She describes the eruption as ‘cloud-like’ She previously suffered from eczema as a child but this rash is different She tells you that although the eruption waxes and wanes, with individual lesions lasting 8 to 12 hours, she is rarely clear of lesions for more than half a day Sometimes she goes to bed with the eruption and wakes clear, but the opposite can also occur She has never experienced angioedema She tells you it is often worse peri-menstrually You question her about possible precipitants; she tells you that the eruption is worse with exercise or a hot bath, but does not appear to be aggravated by pres-sure or cold The eruption is partially attenuated by cetirizine 10 mg daily, which she is tak-ing for her hayfever Her only other medication is occasional ibuprofen for dysmenorrhoea There is no family history of skin lesions Both of her parents are well, although her mother has a diagnosis of osteoporosis and is on thyroxine replacement On close ques-tioning she admits that although circumstances at work are stable and have not changed for a longtime she is experiencing difficulty coping and frequently cries at work

Examination

On examination there are several scattered lesions over her trunk, limbs and face They are composed of well-defined erythematous oedematous plaques surrounded by a pale ‘flare’ (Fig 9.1) The lesions vary in size and shape but not in morphology You are unable to elicit dermographism The lesion that you ringed initially had disappeared by the time she presented to photography 2 hours later, with new lesions developing over adjacent skin

Figure 9.1

• What is this eruption?

• What factors in the history and on examination might be contributing to the eruption?

• How would you investigate this patient?

• What is the management?

ANSWER 9

This patient is suffering from urticaria, which is characterized by wheals or ‘hives’ that represent areas of cutaneous mast cell degranulation, releasing histamine and other mediators, followed by transient oedema and erythema When urticaria persists for more than 6 weeks it is classified as chronic urticaria It represents a tissue reaction pattern and can be precipitated by a variety of stimuli or triggers Many skin eruptions are known which may present with ‘urticated’ lesions that are not transient

There may be more than one precipitant of urticaria in any one affected individual Although there is an element of physical provocation, which you have demonstrated by exercising the patient, the eruption can be present on waking and therefore there is more

to this than cholinergic urticaria The patient is atopic, a factor reported to be ated with urticaria She has made an interesting observation that her urticaria is worse peri-menstrually; the phenomenon of progesterone-provoked urticaria is described It

associ-is more likely, however, that the exacerbation associ-is due to her use of a non-steroidal inflammatory drug (ibuprofen) Importantly, she has clinical features of thyrotoxicosis – chronic urticaria is associated with a number of autoimmune diseases, particularly autoimmune thyroid disease (Graves’ disease), systemic lupus erythmatosus (SLE) and cryoglobulinaemia

anti-Urticarial vasculitis is an important differential diagnosis of chronic urticaria Typically the lesions of urticarial vasculitis are associated with a burning pain and persist for more than 24 hours They may leave post-inflammatory hyperpigmentation or ecchymoses on resolution and can be diagnosed by the demonstration of a leucocytoclastic vasculitis on biopsy of affected skin Where urticarial vasculitis is suspected a work-up for potential systemic vasculitis is important

The initial investigation of this patient would include complete blood cell count, rocyte sedimentation rate, thyroid function tests, antithyroid antibodies (antithyroid microsomal and peroxidase antibodies), basophil histamine release assay Other tests which might be considered: skin biopsy, antinuclear antibodies (ANA), C3, C4 (if features

eryth-of urticarial vasculitis or associated angioedema suggesting acquired C1 esterase ciency secondary to SLE), cryoglobulins and cryoprecipitans (if history of cold-induced urticaria)

defi-It is clear that this patient has symptomatic thyrotoxicosis, so its management and control may significantly improve or even resolve her urticaria In the short term pro-pranolol may be indicated until carbimazole achieves a euthyroid state For any persisting urticaria non-sedating antihistamines (anti-H1) are the mainstay of treatment Response

to different antihistamines can vary so it may be worthwhile trialling different agents, and in some cases doses higher than those required in allergic rhinoconjunctivitis may

be needed The addition of anti-H2 antihistamine such as ranitidine or cimetidine may provide some additional blockade of histamine receptors and can be beneficial, as can the addition of a leukotriene receptor antagonist such as montelukast In general these agents are well tolerated For patients with evidence of autoimmune association and trouble-some persistent urticaria, immunosuppressive therapy with agents such as ciclosporin or methotrexate may be required

• Medication: Aspirin, other nonsteroidal anti-inflammatory drugs, opioids, ACE

inhibitors, radiological contrast media

• Physical urticaria: The most common causes of urticaria frequently coexist:

• Dermatographism/dermographism – firm stroking

• Delayed pressure urticaria – pressure (6–24 h after the application of pressure)

• Cold urticaria – the cold

• Aquagenic urticaria – water exposure

• Cholinergic urticaria – heat, exercise or stress

• Solar urticaria – sun exposure

• Vibratory urticaria – vibration

• Autoimmune disease: Autoimmune thyroid disease, systemic lupus erythematosus,

cryoglobulinaemia

• Autoimmune urticaria: Immunoglobulin G autoantibodies to alpha subunit of

the Fc receptor of the immunoglobulin E (IgE) molecule (35–40 per cent) or, less commonly, anti-IgE autoantibodies (5–10 per cent), can activate basophils to release histamine, the basis of an in-vitro basophil histamine release assay Autoimmune urticaria is closely associated with positive anti-thyroid antibodies

• Viral infections are the most common cause of chronic urticaria in children.

• Foods and food additives: Some patients report the exacerbation of urticaria

associated with the consumption of certain foods, such as spiced food,

strawberries, tinned or preserved food, or certain baked goods Some of these foods contain natural salicylates or other chemical capable of histamine release This reaction is distinct from IgE-mediated type I hypersensitivity to foods, which can be associated with acute urticaria

• Contactants: The onset of localized (or even generalized) urticaria within 30 to

60 minutes of contact with an inciting agent such as latex (especially in health care workers), plants, animals (e.g caterpillars, dander), medications, and food (e.g fish, garlic, onions, tomato)

• Autoinflammatory syndromes: There are rare causes of urticaria such as Muckle–

Wells syndrome (amyloidosis, nerve deafness, and urticaria) and Schnitzler’s syndrome (fever, joint/bone pain, monoclonal gammopathy, and urticaria)

• Idiopathic urticaria is the descriptive term for chronic urticaria for which no

precipitant can be identified

KEY POINTS

• Urticaria is a cutaneous reaction pattern characterized by the degranulation of mast

CASE 10: A TODDLER WITH BROWN PATCHES WHICH URTICATEHistory

A 16-month-old boy presents to the dermatology clinic His mother has noticed a gradual accumulation of ‘brown spots’ on his skin These lesions were not present at birth and the majority appeared as a crop over a 4-month period around his first birthday She feels it

is possible that he will continue to acquire new lesions He had one on his right forearm which has resolved She has noticed that some of the lesions appear to ‘blister’ or become raised after a bath He is otherwise well; he is thriving and enjoys a full diet He has no gastrointestinal symptoms or wheeze There is no family history of similar skin lesions The rest of the family is entirely well

Examination

His height and weight are on the 75th and 91st centiles for his age, respectively He is erative and follows directions He has diffuse, scattered, monomorphic, small oval-round reddish-brown macules concentrated predominantly over his anterior and posterior trunk, but also extending to his neck and with a few scattered lesions on his limbs There are more than 40 of these lesions One lesion just below his xiphisternum, when rubbed, became tran-siently erythematous and swollen (urticaria), a positive Darier’s sign (Fig 10.1) Examination

coop-of his cardiorespiratory system and abdomen is normal He has no lymphadenopathy

Normal

INVESTIGATIONS

Questions

• What are these lesions?

• Would you perform any further tigations?

inves-• What is their management?

Figure 10.1

These lesions represent multiple mastocytomas and the eruption is referred to as caria pigmentosa Darier’s sign describes the development of a wheal and surrounding erythema in a lesion after rubbing (physical degranulation of histamine from mast cells) Mastocytosis is the abnormal accumulation of mast cells within the skin and rarely other organs (liver, spleen or lymph nodes) The differential diagnosis would include lentigines

urti-or melanocytic naevi (if Darier’s sign negative) urti-or xanthogranuloma, histiocytosis X urti-or generalized eruptive histiocytoma (if the lesions were raised or indurated)

All forms of mastocytosis in children have a good prognosis and systemic involvement is rare The majority of cases resolve spontaneously In adults, however, systemic involve-ment may be aggressive or even represent a mast cell leukaemia Symptoms of systemic involvement or of acute degranulation of widespread cutaneous disease include flushing, diarrhoea, nausea/vomiting, abdominal cramps and wheeze Adults may also complain of syncope, angina, headaches and bone pain

Although this young patient has no symptoms of systemic disease, basic investigations would be justified including particularly full blood count, serum tryptase and liver func-tion tests A skin biopsy can be performed if there is diagnostic doubt Mast cell infiltrates can be difficult to identify by routine haematoxylin & eosin staining, and special stains such as Giemsa or toluidine blue, which demonstrate metaochromatic staining of mast cells, are required For patients with rapidly progressive disease and abnormalities of the above investigations, further testing such as bone marrow aspirate and biopsy under the supervision of the haematology department may be indicated Demonstration of activat-ing mutations of the c-kit proto-oncogene would help tailor therapy in aggressive or leukaemic disease (e.g imatinib)

As the skin lesions are likely to resolve spontaneously by the boy’s 10th birthday, no treatment is indicated For patients with skin symptoms antihistamines (H1-blocker) may

be helpful Moderate sunlight exposure can hasten the resolution of diffuse lesions and psoralen–UVA can be offered to adults/older children Patients with numerous lesions or diffuse disease should avoid mast cell degranulating agents such as non-steroidal anti-inflammatory drugs, opiates, alcohol, caffeine, radiological contrast media and abrupt physical degranulation such as a hot bath or other acute temperature change, vigorous rubbing (e.g after a bath or by tight clothing) Exposure to degranulating agents or to allergens (such as hymenoptera stings) can potentially provoke anaphylaxis

KEY POINTS

• Urticaria pigmentosa is characterized by mast cell proliferation and accumulation

CASE 11: ACUTE SOFT TISSUE SWELLING ASSOCIATED WITH

SYSTEMIC SYMPTOMSHistory

A 51-year-old man is referred for an urgent opinion with an 8-week history of intermittent swellings affecting his hands, feet, face and genitalia He also describes intermittent abdomi-nal bloating and pain Over the last three weeks he had attended the accident and emergency department on two occasions The first time, when he presented with lip and tongue swelling but without shortness of breath, he was treated with antihistamines and intravenous hydro-cortisone, but did not require adrenaline or intubation On the second occasion, with acute and severe abdominal pain associated with vomiting, he was admitted for 24 hours under the surgical team for investigation of an acute abdomen,

before his symptoms spontaneously resolved He

does not describe any associated urticaria but does

complain of recent-onset night sweats, weight loss

and low energy levels He is unaware of provoking

factors and feels there is no pattern to the swellings

as they can occur at any time including overnight

He has no previous history of atopy and is on no

medi-cation (he denies taking any over-the-counter

prep-arations such as non-steroidal anti-inflammatory

drugs) He has no family history of swellings or

skin rashes He is a non-smoker and works as a

truck driver

Examination

His skin is normal except for the presence of

uni-lateral left-sided peri-orbital soft tissue swelling

(Fig 11.1) He has smooth, non-tender bilateral

axillary and left-sided inguinal lymphadenopathy

The remainder of his examination is normal

Normal

Urea and electrolytes Normal

Questions

• What are these intermittent swellings?

• What are the possible underlying diagnoses?

• How would you investigate further?

Figure 11.1 INVESTIGATIONS

The skin swellings are angioedema Unusually in this case angioedema is occurring in the absence of urticaria Immunoglobulin E (IgE)-mediated allergic angioedema (provoked by food, drugs, insect bites or latex) or angioedema provoked by physical stimuli (such as sun, heat or cold) is mediated by local release of histamine and is frequently associated with hives

or urticaria The striking other clinical features in this case include the night sweats, weight loss and lymphadenopathy He has anaemia and thrombocytopenia The low complement levels should trigger testing of C-1 esterase inhibitor (C1-INH) levels (suggesting acquired C1-esterase inhibitor deficiency) This patient needs thorough haematological assessment looking for an underlying lymphoproliferative disorder Further investigations include tests for serum lactate dehydrogenase and 2-microglobulin, immunoglobulins and protein electro-phoresis, CT of the chest, abdomen and pelvis as well as lymph node and bone marrow biopsy.When confronted with angioedema in the absence of urticaria it is important to con-sider diseases mediated by bradykinin such as C1-INH deficiency (which can be genetic

or acquired) or induced by angiotensin converting enzyme (ACE) inhibitors Hereditary angioedema is autosomal dominantly inherited, and although there is a high incidence

of de-novo mutations (25 per cent), it usually presents peri-puberty or following gery/trauma, making it a less likely diagnosis in this case Acquired angioedema can be associated with underlying connective tissue disease (systemic lupus erythmatosus, lupus anticoagulant) or lymphoproliferative (particularly B-cell lymphoma) disorders

sur-Common to all of these disorders are symptoms of angioedema, in the absence of urticaria, which can include laryngeal oedema or tongue and/or pharyngeal oedema

of sufficient severity as to cause airway obstruction and, potentially, asphyxia These bradykinin-dependent disorders can also include gastrointestinal symptoms reminiscent

of an acute abdomen with severe pain, nausea, vomiting, or diarrhoea due to oedema of the bowel wall Hypotension is frequently a feature

The management of acquired angioedema includes the use of androgens (such as zol or stanozolol) and antifibrinolytics (such as tranexamic acid) as prophylaxis The emphasis however is on diagnosis and treatment of the underlying disease For heredi-tary angioedema, C1-INH concentrate (extracted from human plasma and freeze dried) is available for intravenous administration

dana-Differential diagnosis of angioedema in the absence of urticaria

!

• IgE mediated allergy (e.g food, latex, drugs)

• Non-IgE mediated histamine release (e.g physical stimuli, drugs)

• Bradykinin mediated:

• Hereditary C1-INH deficiency

• Acquired C1-INH deficiency (associated with lymphoproliferative or connective tissue disorders)

CASE 12: CHRONIC SCALY PLAQUES ON THE KNEES

History

A 25-year-old man presents with a rash on his knees This had gradually worsened over three years In addition he had previously had dandruff and more recently noticed his nails changing, for which his GP treated him for a fungal nail infection, but with no improvement He is a smoker and drinks 35 units of alcohol per week He has noticed an improvement during the summer months and has also developed pains in his elbow and knees His sister had a similar rash over her elbows

Examination

There are erythematous plaques on his knees with clearly defined borders and ing thick scale (Fig 12.1) There is fine scale throughout the scalp and in his external auditory canals Examination of his finger nails reveal three nail plates with pitting and onycholysis

overly-Questions

• What is the diagnosis?

• What are the risk factors for the disease?

• Are his joint pains relevant?

Figure 12.1