Eczema (incl. atopic, contact, discoid, dyshidrotic, herpeticum, seborrhoeic) Flashcards
What is the diagnosis?
- Urticaria
- Scabies
- Atopic eczema
- Psoriasis
- Lichen planus
Atopic eczema
She has poorly defined erythematous patches on her antecubital fossae, a typical site for atopic eczema.
Which treatments would benefit this patient most?
- Oral Flucloxacillin
- Oral Prednisolone
- Oral antihistamines
- Topical Eumovate ointment
- Topical Diprobase ointment
- Topical Dermovate ointment
- Dermol 500 for washing
- Topical Eumovate ointment
- Topical Diprobase ointment
- Dermol 500 for washing
Topical steroids, emollients and soap substitutes form the mainstay of treatment for eczema.
Eumovate is a moderate potency topical steroid and is an appropriate choice.
Dermovate is ultrapotent and too strong to use.
Antihistamines can be useful in eczema but are most helpful in urticaria (histamine mediated itch). Antibiotics are useful for infected eczema and oral prednisolone is reserved for severe flares.
- Eczema herpeticum
- Infected eczema
- Folliculits
- Stress related eczema flare
This is due to HSV infection which can spread rapidly in damaged atopic eczema skin especially if topical steroids are also used. Classically small umbilicated vesicles are seen which then deroof forming punched out erosions.
Eczema herpeticum
Usually caused by HSV1
What are the most important management choices?
- Oral Flucloxacillin
- Oral Prednisolone
- Oral antihistamines
- Topical Eumovate ointment
- Oral Acyclovir
- Stop topical steroid
Acyclovir will treat the HSV. Flucloxacillin is useful for secondary bacterial infection. Stopping topical steroids prevents the HSV infection from spreading further.
- Oral flucloxacillin
- Oral Acyclovir
- Stop topical steroid
A 48-year-old cleaner presented with a 1-year history of an itchy sore rash affecting both her hands. (4)
- Atopic eczema
- Tinea corporis
- Psoriasis
- Dermatomyositis
- Lichen planus
- Pompholyx
- Contact dermatitis
- Porphyria cutanea tarda
- Irritant dermatitis
- Atopic eczema
- Psoriasis
- Contact dermatitis
- Irritant dermatitis
The differential diagnosis for hand dermatitis is wide with eczema, psoriasis, contact and irritant dermatitis at the top of the list.
Which questions in the history are important to help you make the diagnosis?
- Do you wear leather shoes?
- Does the rash clear when you are on holiday?
- Are you right or left handed?
- Do you get a reaction to wristwatches, belts or cheap jewellery?
- Do you get soreness or ulcers in the mouth?
- Is there a family history of eczema or psoriasis?
- Did you have eczema as a child?
- Does anyone at home have a similar rash?
- Do you wear gloves at work?
If the rash clears on holiday and mainly affects the dominant hand this indicates a contact or irritant dermatitis related to her work. A family history of atopy or psoriasis or a past history of either disease may indicate an endogenous cause. If she doesn’t wear gloves while using chemicals at work this suggests an irritant dermatitis.
- Does the rash clear when you are on holiday?
- Are you right or left handed?
- Is there a family history of eczema or psoriasis?
- Did you have eczema as a child?
- Do you wear gloves at work?
On examination, which other areas of the body would you examine to help determine the diagnosis? (4)
- Ears
- Eyes
- Scalp
- Nails
- Soles of feet
- Knees and elbows
Psoriasis and eczema can affect the scalp and nails. If the soles of the feet are also involved this suggests an endogenous cause rather than a contact or irritant dermatitis. Mild psoriasis may present as scaling on the elbows and knees.
- Scalp
- Nails
- Soles of feet
- Knees and elbows
She admits to not wearing gloves at work and had no personal or family history of atopy or psoriasis. Examination of the rest of her skin is normal. Her nails are not affected. What are the appropriate steps to take next?(4)
- Dermol 500
- Eumovate cream
- Dovonex cream
- Dermovate ointment
- Advise gloves at work
- Advise her to give up her job
- Patch tests
With no suggestions of intrinsic disease contact dermatitis and irritant dermatitis are the two likely diagnoses. Dermol 500 can be used as a soap substitute. Dermovate ointment once daily is appropriate for disease on the palms and soles. As this is an eczematous condition ointment should be used rather than a cream. She should use gloves when in contact with chemicals or when doing wet work. Patch tests will confirm whether she has a true allergy to one of the chemicals or whether she is suffering from an irritant reaction. With the above treatment regime her disease should be controllable and it is unlikely that she will have to give up her work
- Dermol 500
- Dermovate ointment
- Advise gloves at work
- Patch tests
NB: dermatitis not year 3 Sofia
A lady presents with a number of very itchy lesions affecting her body but not her face. The itching is worse when warm such as in bed. No one else is affected but is persistent.
- Bowens disease
- Tinecorporis
- Eczema discoid
Discoid eczema, also known as nummular dermatitis, is a common type of dermatitis. It can occur at any age and affects males and females equally.
What are the clinical features?
- Weepy multiple lesions
- Erythematous lesions
- Well dermarcated
- All of the above
ALL
The majority of patches are round or oval, hence the name ‘discoid‘ or ‘nummular’ dermatitis, which refers to their disc or coin shape. They can be several centimetres across, or as small as two millimetres. The patches are pink, red, or brown and well defined. They have a dry cracked surface or a bumpy, blistered or crusted surface. Discoid eczema may be extremely itchy, or scarcely noticeable. The skin between the patches is usually normal, but may be dry and irritable. Severe discoid eczema may generalise, with numerous small to large itchy lesions appearing all over the body due to autoeczematisation reaction. The patches may clear up without leaving a sign. However, in darker skins, marks may persist for months. These may be dark brown (postinflammatory hyperpigmentation) or paler than surrounding skin (postinflammatory hypopigmentation).
How would you treat this?
- Topical antibitoics
- Topical steroids
- Systemic steroids
- Oral antibitoics
- Topical steroids
Topical steroids best but other treatments also appropriate:
Topical steroids are anti-inflammatory creams or ointments; may clear the dermatitis and reduce irritation. The stronger products are applied to the patches just once or twice daily for 15 days. Mild ones such as hydrocortisone are safe for daily use if necessary.
Protect the skin from injury - often starts off as minor skin injuries, so protect all skin carefully. If the hands are affected, use gloves etc
Emollients - include bath oils, soap substitutes and moisturizing creams. They can be applied to the dermatitis as frequently as required to relieve itching, scaling and dryness. Emollients should also be used on the unaffected skin to reduce dryness. It may be necessary to try several different products to find one that suits. Many people find one or more of the following helpful: aqueous cream, glycerine & cetomacrogol cream, white soft paraffin/liquid paraffin mixed, wool fat lotions.
Oral or topical antibiotics - (most often flucloxacillin) are important if the dermatitis is weeping, sticky or crusted. Sometimes nummular dermatitis clears completely on oral antibiotics, only to recur when they are discontinued.
Oral antihistamines - pills may reduce the itching, especially at night-time. They do not clear the dermatitis. Newer non-sedating antihistamines appear less useful for this condition, possibly because part of the effect of the conventional type is due to making the person sleepy.
Phototherapy - UV light treatment several times weekly can help. It may take several months.
Systemic steroids by mouth or injection are reserved for severe and extensive cases of nummular dermatitis. Systemic steroids are usually only necessary for a few weeks.
Nummular dermatitis has a tendency to recur when the treatment has been stopped. Make sure the skin is kept well moisturised, and protected from injury. Eventually, clears up completely.
Define eczema.
A pruritic papulovesicular skin reaction to endogenous or exogenous agents.
Pompholyx/dyshidrotic eczema shown on bottom right. Varicose on top right. Asteatotic eczema with “crazy paving” on the bottom left on shins.
How common is eczema? (atopic/contact)
Contact - prevalence 4%
Atopic - usually in first year of line, childhood incidence 10-20%
What is the aetiology of these types of eczema?
- Exogenous
- Endogenous
- Irritant
- Contact
- Atopic
- Seborrhoeic
- Varicose
Numerous varieties caused by a diversity of triggers.
- Exogenous: Irritant, contact, phototoxic.
- Endogenous: Atopic, seborrhoeic, pompholyx, varicose, lichen simplex.1
- Irritant: Prolonged skin contact with a cell-damaging irritant (e.g. ammonia in nappy rash).
- Contact: Type IV delayed hypersensitivity to allergen (e.g. nickel, chromate, perfumes, latex
- and plants).
-
Atopic: Two major models currently exist to explain the pathogenesis:
- 1 Impaired epidermal barrier function due to intrinsic structural and functional skin abnormalities
- (predominant model).
- 2 Immune function disorder in which Langerhans cells, T cells and immune effector cells modulate an inflammatory response to environmental factors (traditional model).
- Seborrhoeic: Pityrosporum yeast seems to have a central role.
- Varicose: Increased venous pressure in lower limbs.
What are the risk factors of eczema?
Age <5 years - 45% of patients diagnosed by 6months of age and 85% by 5yrs. Early onset associated with persistance.
FH
Allergic rhinitis - in 50-80%. Allergen sensitisation and immune dysregulation are thought to be important components in atopic disease.
Asthma - in 40-50%
Anthelmintic treatment in utero - Antenatal exposure to helminth infection is believed to impact upon the development of the fetal immune response, leading to the hypothesis that anthelmintic treatment in pregnancy may modulate disease incidence in childhood
Active and passive exposure to smoke
What is the pathophysiology of eczema?
Impaired skin barrier function (there may be genetics involved e.g. filaggrin gene)
Acute phase - Th2 mediated immune response following sensitisation –> over-expression of IL-4, 5, 13 –> more IgE production and peripheral eosinophilia
Chronic - can be as a result of perisistent inflammation and scratching –> thick, lichenified skin. Predominantly a Th1 response and high IL-12 levels.
What are the differences between contact and irritant dermatitis?
Contact = ALLERGIC CONTACT DERMATITIS - allergic reaction; T cell mediated, there may be a lag between exposure and reaction e.g. to jewellery; if affecting hands then affects PALMS
Irritant = IRRITANT CONTACT DERMATITIS - due to the direct effect of something over a long period of time; if affects hands then affects BACK of hands
What kind of eczema does this patient have? Describe the features.
Atopic eczema is the commonest form of eczema, affecting up to 20% infants and at least 1% adults. In nearly all patients, it begins in infancy and presents with an intensely itchy rash with certain characteristics:
- Association with personal or family history of asthma, rhinitis
- Symmetrical distribution
- Flexural accentuation in childhood and adolescence
- Flare-ups
What kind of eczema does this patient have and what are the features?
Seborrhoeic eczema affects 5 to 10% adults. The infantile form usually clears by 6 to 12 months of age. Although prevalent in the scalp (dandruff), it may affect face, flexures and trunk. The main features are:
- Flaky skin
- Minimal pruritus
- Response to antifungal agents
What kind of eczema does this patient have and what are the features?
Discoid or nummular eczema can arise at any age. It often starts as a single patch at the site of injury – for example, a scratch, thermal burn, insect bite. In time, more well-defined round or oval eczematous plaques appear on limbs and trunk. Itch may be severe.
- Asymmetrical distribution
- Blistering or crusted plaques
- Relative resistance to topical steroids
What kind of eczema does this patient have and what are the features?
Dry discoid eczema is a form of asteatotic eczema and usually appears on the limbs.
- Round dry red patches
- Minimal to mild pruritus
- Response to emollients and mild topical steroids
What kind of eczema is this?
Eczema craquelé describes a crazy-paving appearance of astetatotic eczema. It is most frequently observed on the shins of middle-aged or elderly patients during the winter months.
What kind of eczema is this and what are the features?
Venous stasis eczema affects the lower legs. There may be a history of prior cellulitis or deep venous thrombosis. Venous eczema tends to be very chronic – management of deep venous disease may help, including vein surgery and graduated compression hosiery. Signs of venous disease include:
- Brawny pigmentation due to haemosiderin deposition
- Chronic oedema
- Venous ulceration
- Lipodermatosclerosis (circumferential hardened skin of ankle)
Name one option on each step of the steroid ladder used to treat eczema. How long can steroids me taken?
- Very potent = Dermovate
- Potent = Betnovate
- Moderate = Eumovate
- Mild = Hydrocortisone 1%
Summary of potency: 1% HC > Eumovate >Betnovate >Elocon > Dermovate
Better to “hit hard” for a few days rather than to take weak steroid for long time (so you don’t always have to start at bottom of ladder). Use for 2 days after resolution (max 5 days on face)
What do these lesions show?
- Urticaria = raised central inflammation with flare around it
- Top = scabies (pointing to burrows) – sarcoptus scabei. Usually very quick onset.
- Middle bottom = psoriasis on extensor surfaces
- Lichen planus = shiny, flat, topped papules which are itchy. Purplish in colour. Inside wrists, ankles, back, white lines on buccal mucosa and genitals. More common in middle aged people. Fairly common. Take a punch biopsy. Treat with topical steroids. Aetiology unknown but could be linked to Hep C/medications.
What are these?
TL - dermatomyositis, usually also causes a rash on teh face and swelling of cheeks and eyelids
BL - tine corporis - fungal infection; annular lesion with pale centre and erythematous outer ring (opposite of discoid eczema)
TR - pomphlyx blisters
BR - porphyria cutanea tarda - rare disorder characterized by painful, blistering skin lesions that develop on sun-exposed skin; defect in breaking down porphyrins in blood which accumulate and cause photosensitivity. Affected skin is fragile and may peel or blister after minor trauma.
