Dermatology

Question 1

What is eczema?
How is it managed?
(RECAP)

Answer 1

Break in the skin barrier allowing for microbes, irritants and allergens to infiltrate and produce an immune response with inflammation.

Management:
Avoid activities which could break down the skin barrier i.e. hot baths, scratching skin etc.
Apply emollients- thin creams (E45, Aveeno) or thick ointments (Hydromol, Dirpobase). Apply plenty and often, and before bed.
Can apply topical steroids to reduce flares, should encourage using the lowest potency for the shortest time (risk of skin thinning, dependency, telangiectasia).

Topical steroid potency:
Mild- hydrocortisone
Moderate- eumovate
Potent- betnovate
V. potent- dermovate

Bacterial infections (commonly staph.aureus) need treating with flucloxacillin (oral but severe may need admission for IV)

Question 2

What is eczema herpeticum?
How does it present?
How is it managed?
(RECAP)

Answer 2

Viral skin infection by HSV (commonly), but also varicella zoster virus.

Typically eczema patient with erythematous widespread vesicular rash with systemic features of lethargy, fever and irritability.

Take viral swab of vesicle, but often manage based on clinical picture.

Mild/moderate- oral acyclovir. Severe- IV acyclovir.

Can become emergency if untreated, especially in immunocompromised child. Also risk of bacterial superinfection (treat with Abx)

Question 3

What are the main types of psoriasis?
How do plaques present in children?
(RECAP)

Answer 3

Plaque psoriasis- most common in adults.

Guttate psoriasis- Second most common, more common in children. Red small erythematous papules across the trunk and limbs. These later become plaques which self resolve within 3-4 months. usually occur post strep-throat.

Pustular psoriasis- Non infective pus collection under the erythematous areas. Can become systemically unwell so need hospital admission.

In children the plaques of psoriasis are likely to be smaller, softer and less prominent.

Question 4

How is psoriasis managed?
What are the associations of psoriasis?
(RECAP)

Answer 4

Management: (same as adults)
Regular emollients
(1) Potent topical steroid and Vit D analogue to be used once daily, one in morning and one in the evening. Use for 4wks.
(2) No improvement after 8wks use a Vit D analogue BD.
(3) Use a potent topical steroid BD for 4wks.
Secondary management includes phototherapy and biologics.

Nail psoriasis; pitting, onycholysis, thickening, discolouration, ridging etc.
Psoriatic arthritis; presenting after 10yrs of having the skin changes
Psychological implication; depression, anxiety, social exclusion etc.

Question 5

How is acne vulgaris managed?

RECAP

Answer 5

Mild- may not need treatment.

(1) Single topical treatment- benzoyl peroxidase, topical retinoids.
(2) Combination therapy- 2 of benzoyl peroxidase, topical retinoids, topical Abx.
(3) Oral Abx- tetracycline for 3 months (not suitable for <12yrs old)
(3) In girls consider COCP
(4) Oral isotretinoin (Roaccutane)- needs specialist prescription.

Roaccutane side effects-
Highly teratogenic; counsel about pregnancy, stop 1 month before becoming pregnant
Dry lips and lips
Photosensitivity to light
Depression, suicidal ideation- therefore need to consider mental health status before commencing treatment

Question 6

What is measles?
How does it present?
How is it managed?

Answer 6

Previously first disease.

Highly contagious respiratory droplets, developing symptoms of fever, conjunctivitis and coryzal symptoms 10-12 days post exposure.

2 days post fever- koplik spots (white spots on the buccal mucosa) which are diagnostic of measles.
3-5 days post fever- macular flat rash appearing on the face, starting behind the ears.
Within 7-10 days of symptoms starting they should self resolve.
Should stop isolating 4 days after symptoms have resolved.

Notifiable disease

Question 7

What are the complications of measles?

Answer 7

Dehydration
Death
Diarrhoea
Pneumonia
Hearing loss
Vision loss
Encephalitis
Meningitis

Question 8

What is Scarlet fever?
How does it present?
How is it managed?

Answer 8

Previously second disease.
Due to Group A strep (pyogenes), commonly post tonsillitis.
Get macular erythematous blotchy rash beginning at the trunk and moving up.

Also presents with:
Fever
Lethargy
Facial flushing
Strawberry tongue
Cervical lymphadenopathy

Manage with 10 day course of phenoxymethylpenicillin.
Notifiable disease. Should not return to school until 24hrs post Abx starting.

Question 9

What is rubella?
How does it present?
What are the complciations?

Answer 9

Previously third disease.
Very contagious respiratory droplets, symptoms within 2 wks of infection. Erythematous macular rash (milder than measles) beginning at the face and lasting 3 days, with mild fever, lethargy and coryzal symptoms. Patients have post-auricular and occipital lymphadenopathy.
Self limiting with analgesia and hydration. Children should attend school 5 days after rash disappears and stay away from pregnant women.

Complications:
Congenital rubella syndrome- triad of deafness, blindness and congenital heart disease
Thrombocytopenia
Encephalitis

Notifiable disease

Question 10

What is parvovirus B19?
How does it present?
What are the complications?

Answer 10

Previously fifth disease/slapped cheek syndrome.

Mild fever and coryzal symptoms.
2-5 days later get red rash across cheek (slapped cheek)
Few days later get net like rash across the trunk and limbs

Illness and rash are self limiting and will resolve within 1-2wks. Children do not need to stay off school once rash appears.

Complications occur in immunocompromised, pregnant and patients with haematological conditions.
Aplastic anaemia
Pregnancy complications and foetal death
Meningitis
Encephalitis
Rarely hepatitis, myocarditis

Question 11

What is roseola infantum?

How does it present?

Answer 11

Previously sixth disease.
Caused by human herpes virus.

Presents with high fever (up to 40 degrees) 1-2wks after infection. Fever lasts 3-5 days and spontaneously resolves. Then mild erythematous rash appears across the torso, limbs and face (non-itchy), lasting 1-2 days.

Children recover fully within a wk.
Complications include febrile convulsions.

Question 12

What is erythema multiforme?

How is it managed?

Answer 12

Erythematous target lesion rash caused by either infection or medication.

Rash appears spontaneously, is widespread, itchy and target lesion shaped.

Mild cases resolve spontaneously. Treat underlying cause, if unknown then CSR for mycoplasma pneumoniae.
If severe i.e. involving the oral mucosa- admit for Iv fluids, steroids and analgesia.

Question 13

What are the acute causes of urticaria?

RECAP

Answer 13

<6wks
Allergies
Chemical contact
Insect bites
Viral infections
Medications

Question 14

What are the causes of chronic urticaria?

RECAP

Answer 14

> 6wks
Chronic idiopathic- unknown cause.
Chronic inducible- dermatographia, hot/cold weather, exercise, strong emotions, sunlight, change in temperature.
Autoimmune- Associated with autoimmune conditions i.e. SLE

Question 15

How is urticaria managed?

Answer 15

Anti-histamines. Fexofenadine of choice in chronic urticaria

In flares can consider oral steroids.

Question 16

What are the complications of chicken pox?

Answer 16

Dehydration
Conjunctivitis
Encephalitis
Pneumonia
Bacterial superinfection

If lies dormant can develop shingles.

Question 17

What is hand, foot and mouth disease?
How does it present?
How it it managed?

Answer 17

Coxsakie A viral infection (3-5 days intubation)

Initially get URTI symptoms i.e. lethargy, dry cough.
Then 1-2 days later present with mouth ulcers. Soon after develop widespread vesicles, most prominent at the hands, feet and mouth. Rash can be itchy.

Self resolving within 7-10 days, encourage fluid and analgesia. Highly contagious so be cautious of spreading.
Complications are rare but include encephalitis, bacterial superinfection and dehydration.

Question 18

What is Molluscum Contagiosum?
How is it managed?
(RECAP)

Answer 18

Poxvirus causing small flesh coloured raised papules with central dimple.

Self resolve within 18 months.
Be cautious of spreading and ensure not to pick/scratch the papules as they can result in scarring.

Question 19

What is pityriasis rosea?
How is it managed?
(RECAP)

Answer 19

Unknown cause of rash.
Have prodromal flu symptoms i.e. headache, tired etc. Initially appears with herald patch. Then 2 days later develop a widespread consisting of faint red/pink oval lesions.

Rash self resolves within 3 months. No treatment is required.
If itchy and difficulty sleeping can use anti-histamines, emollients or topical steroids.

Question 20

What is seborrhoeic dermatitis?
What are the different types?
How is it managed?
(RECAP)

Answer 20

Malassazei yeast infection of the sebaceous glands. Therefore affecting scalp, nasolabial folds and eyebrows commonly.

Infantile SD (cradle cap):
Crusty flaky scalp, self resolving within 4 months of birth but can last up to 1 yr. Encouraged to rub baby/vegetable/olive oil into scalp, gently brush the scalp and wash off. If not working apply white petroleum jelly overnight and wash off the next morning. If not then use clotrimazole/miconazole for 4 wks.

SD of scalp (dandruff):
More common in adults. Apply ketoconazole shampoo 5 minutes before washing off.

SD of face and body:
Red, itchy, crusty, flaky skin. Try clotrimazole/miconazole for 4wks. Local areas of inflammation may benefit from topical steroids.

Question 21

What is a nappy rash?
What are the RF of developing a nappy rash?
How does a nappy rash appear?

Answer 21

Contact dermatitis from friction between the skin and nappy, also contact between the dirty nappy and skin.
Commonly affecting 9-12 months. Can progress to develop bacterial or candida infection.

RF:
Delay in changing nappy
Poorly absorbent nappy
Recent Abx (candida rash)
Diarrhoea
Pre-term
Use of irritant soaps

Appearance:
Individual red patches
Sparring of the folds
Small red papules
Uncomfortable, infant distressed
If long standing can lead to ulceration and erosion.

Question 22

How is a nappy rash differentiated between a candida infection?
How is a nappy rash managed?

Answer 22

Candida-
Large macules
Folds are not sparred
Well demarcated scaly border
Circular lesions i.e. like ringworm
Check for signs of oral thrush i.e. white coating of tongue

Management:
Change to more absorbent nappies
Change nappies more frequently
Spend more time w/o a nappy
Ensure nappy area dry before replacing nappy
Use water/alcohol free wipes to clean nappy area

Bacterial infection- topical Fucidic acid or oral flucloxacillin.
Candida- topical miconazole/clotrimazole

Question 23

How is scabies managed?

RECAP

Answer 23

Permethrin cream, repeated after one week. Ensure to apply when dry to reduce absorption. Keep for 8-12hrs then wash off.
All clothes, bedsheets etc should be washed with hot water to kill mites.
Itching can persist up to 4wks post treatment.

Question 24

How is headlice managed?

Answer 24

Dimeticone (Hedrin) applied and left for 8hrs/overnight.
Then repeat 7 days later to kill lice which may have hatched since.

Fine combs can be used for detection of headlice.

Question 25

What is impetigo?
How is it managed?
What are the complications?
(RECAP)

Answer 25

Staph.aureus skin infection.

Non-bullous- Commonly affecting around the skin and nose, with characteristic golden crust appearance, usually systemically well.
Manage with topical hydrogen peroxide cream. If more widespread, manage with oral flucloxacillin.
Contagious so children should stay off school until the rash ahs crusted over OR 48hrs of Abx treatment.

Bullous- More common in neonates/under 2yrs old. Epidermolytic toxins cause formation of fluid filled vesicles which burst to give a golden appearance. Usually systemically unwell and feverish. If more severe and widespread- SSSS (staphylococcal scalded skin syndrome.
Manage with isolating since contagious. Take swab to find diagnosis and sensitivities. Usually manage with oral flucloxacillin but may need IV if severe or at risk of complications.

Complications include SSSS, sepsis, Scarlet fever and cellulitis.