Paediatric Dermatology Flashcards
Urticaria (hives) - state the following:
- Pathophysiology
- Presentation (including any red flags)
- Management
Pathophysiology:
- Superficial swelling of the skin, leading to a red, raised, itchy rash
- Caused by release of histamine from mast cells, in response to a trigger
- Can be acute or chronic, localised or widespread
Presentation:
- Migratory, well-circumscribed, erythematous plaques on the skin surface
- Itchy
- Usually describe a trigger e.g. allergy, insect bite
Red flags - consider anaphylaxis e.g. facial swelling, SOB etc.
Management:
- Avoidance of triggers
- Non-sedating antihistamine e.g. Fexofenadine or Cetirizine
- If severe, short course of an oral corticosteroids
State some differentials for an acute rash (non-specific, viral, bacterial, other)
Non-specific:
- Viral exanthem
- Heat rash
- Urticaria
- Eczema
- Cellulitis
Viral:
- Chicken pox
- Measles
- Rubella
- Roseola
- Parvovirus B19
- Pityriasis rosea
- Hand, foot and mouth disease
Bacterial:
- MENINGITIS
- Scarlet fever
- Impetigo
- Staphylococcal scalded skin syndrome (SSSS)
Other:
- Erythema multiforme
- Eczema herpetiform
- Kawasaki disease
- Scabies
- Ringworm
Which symptoms and questions should you ask about for a patient presenting with an acute rash
Rash:
- When did it start
- Where on the body did it start and progression since
- Any triggers
- Fever
- Malaise
- Headache / visual disturbance / neck stiffness
- Loss of appetite
- Abdominal pain
- Irritability
- Myalgia / arthralgia
Questions:
- Up to date on immunisations?
- Any unwell contacts
- New medications
State some causes of acute urticaria and chronic urticaria
Acute (< 6 weeks):
- Allergy e.g. food, pets, medication
- Contact e.g. stinging nettles, latex
- Viral infection
- Insect bite
Chronic (>6 weeks):
- Chronic idiopathic with no clear trigger
- Chronic inducible with triggers e.g. strong emotions, exercise, weather change, sunlight, pressure Dermographia
- Autoimmune associated e.g. SLE
State some differential diagnoses for urticaria
Erythema multiforme minor
Contact dermatitis
Atopic eczema
Chronic pruritus
Pemphigoid (bullous) and dermatitis herpetiformis
Polymorphic eruption of pregnancy
Urticaria pigmentosa
Urticarial vasculitis
When might you consider referring to a specialist for a patient with urticaria
- Painful and persistent (suspect vasculitic urticaria).
- Symptoms are not well controlled on antihistamine treatment
- Angio-oedema and no wheals, that do not respond to first-line treatment
- Chronic inducible urticaria, difficult to manage in primary care
Able to prescribe monoclonal antibodies
State the six red rashes (viral exanthems)
First disease: measles
Second disease: scarlett fever (strep A)
Third disease: rubella (german measles)
Fourth disease: Ritter’s disease (staphylococcal scalded skin syndrome)
Fifth disease: parvovirus B19 (slapped cheek syndrome)
Sixth disease: roseola infantum
Measles - state the following:
- Pathophysiology
- Presentation (including any red flags)
- Investigations
- Management
Pathophysiology:
- Caused by Measles morbillivirus
- Extremely contagious
- Incubation period of up to 2 weeks
- Normally would be covered by the MMR vaccine
Presentation:
- Incubation period of up to 2 weeks
- Prodromal period with fever, cough, coryza, conjunctivitis and Koplik spots
- Widespread maculopapular rash, 3-5 days after fever which starts behind the ears and spreads cranio-caudally
Red flags
- SOB
- Uncontrolled fever
- Convulsions
- Altered consciousness
Investigations:
- 3-14 days after rash use measles-specific antibody testing
- 1-3 days after rash use RNA PCR
Management:
NOTIFIABLE DISEASE
Generally self-limiting & no specific antiviral treatment
- Maintain hydration
- Analgesia
- Antipyrexics
- Treat secondary opportunistic infections
- Vitamin A if < 2 years old
State some complications of measles if untreated
Most common:
- Diarrhoea and dehydration
- Pneumonia
- Acute otitis media
Less common:
- Meningitis / encephalitis
- Hearing / vision loss
- Death
State some advice you could give to parents if child has measles
- Stay away from nursery / school / work for at least 4 days after the initial development of the rash (ideally until full recovery)
- Avoid contact with vulnerable people e.g. unvaccinated, pregnant, immunocompromised
Safety net for:
- SOB
- Uncontrolled fever
- Convulsions
- Altered consciousness
Contact dermatitis - state the following:
- Pathophysiology
- Presentation
- Investigations
- Management
Pathophysiology:
- Skin reaction caused by an external agent
- Can either be irritant (non-immunological) or allergic (immunological), and acute or chronic
- Very common, especially work related irritant contact dermatitis, can be from acute mild irritants e.g. water, soaps, solvents or from more toxic substances e.g. acids
Presentation:
Generally well defined areas where contact has occurred
- Pruritus
- Burning
- Erythema
Acute
- Swelling and blistering
Chronic
- Hyperpigmentation, fissuring, and scaling
Investigations:
- Patch testing for allergic contact dermatitis
- Irritant contact dermatitis is a diagnosis of exclusion if patch testing is negative
Management:
Irritant
- Washing off the irritant
- Thick emollient protection
- Avoidance of future exposure
Allergic
- Low potency topical corticosteroid e.g. Hydrocortisone 2.5%
- Avoidance of allergen
Human papillomavirus (HPV) - state the following:
- Pathophysiology
- Presentation
- Investigations
- Management
Pathophysiology:
- Very common virus group, more than 100 different types of HPV
- Leads to cutaneous warts (infection of keratinocytes with HPV)
- Most common STI, 90% cases resolve within 2 years with no complications
- Spreads via close contact during sexual contact, vaginally, orally or anally, or sharing sex toys
Presentation:
Usually asymptomatic
- Sometimes painless lumps in genital area
Investigations:
- HPV test during cervical screen
- May screen for in sexual health clinics with MSM (higher risk)
Management:
- No treatment
- Treat complications such as genital warts or cervical cell changes
- Consider treating cutaneous warts if painful, cosmetically unsightly, persistent or personal request
- Treatment options (non-facial) e.g. topical salicylic acid, cryotherapy or both
Suggest when you would refer to secondary care for management of cutaneous warts
- Facial wart
- Extensive warts
- Uncertain diagnosis / suspicious diagnosis
- Multiple persistent warts and compromised immunity
Hand, foot and mouth disease - state the following:
- Pathophysiology
- Presentation
- Investigations
- Management
Pathophysiology:
- Characteristic rash caused by Coxsackie A virus
Presentation:
Incubation period 3-5 days, followed by 1-2 days of URTI symptoms e.g. sore throat, dry cough, fever
- Painful mouth ulcers = key feature
- Followed by widespread blistering red spots, most on hands feet and around mouth
- Rash may be itchy
Investigations:
- Clinical appearance of rash
Management:
No treatment! Supportive care
- Adequate fluid intake
- Analgesia
Rash and illness should resolve after 7-10 days
HIGHLY CONTAGIOUS - avoid sharing bedding and careful with dirty nappies
Erythema multiforme - state the following:
- Pathophysiology
- Presentation
- Investigations
- Management
Pathophysiology:
- Hypersensitivity reaction, resulting in an erythematous rash
- 2 main causes are viral infections and medications
- Specifically, herpes simplex virus and mycoplasma pneumoniae
Presentation:
- Widespread, itchy erythematous rash
- Target lesions
- Sore mouth (stomatitis)
- Flu-like symptoms e.g. headache, myalgia
Investigations:
Important to identify underlying cause
Generally clinical decision based on appearance if clear cause e.g. cold sores
- If unsure of underlying cause, may do chest x-ray for mycoplasma pneumoniae
Management:
Generally supportive if clear underlying cause, should resolve in 1-4 weeks
- Severe cases may require hospital admission, IV fluids, analgesia and steroids, antibiotics/antiviral if infection present
Eczema herpeticum - state the following:
- Pathophysiology
- Presentation
- Investigations
- Management
Pathophysiology:
- Viral skin infection
- Caused by either herpes simplex or varicella zoster
- Mostly commonly caused by herpes simplex 1 (associated with a cold sore in a close contact)
- Usually occurs in individuals with underlying skin conditions (allows virus to enter skin and cause infection)
Presentation:
Typically patient which suffers from eczema already
- Widespread, painful vesicular (pus) rash
- Lymphadenopathy
- Fever
- Lethargy / irritability
- Poor oral intake
Investigations:
- Viral swabs (although treatment usually started based on clinical appearance)
Management:
- Aciclovir (oral if mild-mod, IV if severe)
Scarlett fever - state the following:
- Pathophysiology
- Presentation
- Investigations
- Management
Pathophysiology:
- Associated with group A step (usually tonsillitis or impetigo), caused by production of an exotoxin
Presentation:
- ‘Sandpaper’ rash & strawberry tongue
- Red, blotchy, macular rash which starts on trunk and spreads outwards (develops 24-48 hours after flu-like symptoms)
- Cervical lymphadenopathy
- Sore throat
- High fever
- May have red, flushed cheeks
- Associated headache, fatigue, lethargy
Investigations:
- Clinical diagnosis, throat swabs and blood tests not routinely indicated
- But throat swab for culture of Group A streptococcus (GAS) if clinical uncertainty
Management:
NOTIFIABLE DISEASE
- Oral Penicillin V for 10 days
- Keep off school until 24 hours after antibiotics have started
Rubella (German measles) - state the following:
- Pathophysiology
- Presentation
- Investigations
- Management
Pathophysiology:
- Caused by rubella virus
- Highly contagious, spread by respiratory droplets (symptoms appear 2 weeks after exposure)
Presentation:
- Mild erythematous macular rash (milder than measles), which starts on face and spreads to body
- Postauricular, suboccipital and cervical lymphadenopathy
- Sore throat
- Mild fever
- Joint pain
Investigations:
- Clinical diagnosis
Management:
NOTIFIABLE DISEASE
- No specific treatment, usually mild and self limiting
- Keep patient off school: 7 days before and 7 days after rash
- Avoid pregnant women
State 2 conditions associated with group A strep infection
(Associated with tonsilitis)
- Post-streptococcal glomerulonephritis
- Acute rheumatic fever
State some complications of rubella if left untreated
- Conjunctivitis
- Thyroiditis
- Arthritis
- Encephalitis
**Dangerous in pregnant women (congenital rubella syndrome)
Parvovirus B19 (slapped cheek syndrome) - state the following:
- Pathophysiology
- Presentation
- Investigations
- Management
Pathophysiology:
- Also known as fifths disease, slapped cheek syndrome and erythema infectiosum
- Caused by Parvovirus B19 virus
Presentation:
- Non-specific viral symptoms e.g. myalgia and lethargy
- Bright red rash on cheeks (develops 2-5 days later)
- Lace like pink rash follows on limbs and occasionally trunk (raised and itchy)
Investigations:
- Clinical diagnosis
- Can be confirmed with blood tests: Parvovirus serology (IgG and IgM) or PCR
Management:
- No specific treatment- reassurance and emollients
- No school exclusion required (infectious before rash evident)
- Ice cold flannel can relieve discomfort of cheeks
- Avoid pregnant women
State some complications of untreated Parvovirus B19 (slapped cheek syndrome)
- Aplastic anaemia
- Encephalitis or meningitis
- Rare but hepatitis, myocarditis or nephritis
**Dangerous in pregnant women
Roseola infantum - state the following:
- Pathophysiology
- Presentation
- Investigations
- Management
Pathophysiology:
- Also known as fifth disease
- Caused by herpes virus 6 (sometimes 7)
Presentation:
- Sudden high fever
- Coryzal symptoms
- Lymphadenopathy
- Non-itchy mild erythematous macular rash across face, body, arms and legs
Investigations:
- Clinical diagnosis
- Some labs confirm HHV-6 infection by serology or PCR
Management:
- No specific treatment, usually mild and self-limiting
- Don’t need to be kept off nursery
State the main complication to be aware of for Roseola infantum
Febrile convulsions (due to very high temperatures)
Chicken pox - state the following:
- Pathophysiology
- Presentation
- Investigations
- Management
Pathophysiology:
- Caused by the varicella zoster virus, highly contagious
- Spread through direct contact with lesions, or by respiratory droplets
- Incubation period of between 10 days - 3 weeks
- Once infected, will develop immunity and will not be affected again
Presentation:
- Widespread, vesicular erythematous rash, which starts on trunk or face and spreads to body (over 2-5 days)
- Lesions eventually scab over
- Fever (often first symptom)
- Itchy
- General fatigue and malaise
Investigations:
- Clinical diagnosis
Management:
- Usually self-limiting
- Can use calamine lotion and antihistamines (Chlorphenamine) for itching
- Aciclovir in vulnerable patients e.g. immunocompromised, pregnant women with no previous exposure
- Kept off school and avoid vulnerable groups, until lesions crusted over
State some complications of chicken pox
- Dehydration
- Bacterial superinfection
- Conjunctival lesions
- Pneumonia
- Encephalitis
State 2 conditions that may arise if varicella zoster virus is reactivated later in life, and where the virus ‘hides’
1) Shingles
2) Ramsay-Hunt syndrome
‘Hides’ in the sensory dorsal root ganglion cells and cranial nerves
Infantile seborrhoeic dermatitis (cradle cap) - state the following:
- Pathophysiology
- Presentation
- Investigations
- Management
Pathophysiology:
- Inflammatory condition affecting sebaceous glands
- Thought that Malassezia yeast colonise the skin
Presentation:
- Crusty, flaky scalp
Management:
- Generally self-limiting
- Usually resolves by 4 months, but can last up to 12 months
- Treatments include brushing baby oil on head and washing off (use vaseline overnight as an alternative)
- Second line is anti-fungal cream e.g. Clotrimazole for up to 4 weeks
- Referral to dermatologist if refractory to treatment
Nappy rash (contact dermatitis) - state the following:
- Pathophysiology
- Presentation
- Investigations
- Management
Pathophysiology:
- Contact dermatitis caused by friction between nappy and skin and contact of skin with urine and faeces for a long time
- Most common between 9-12 months
- Can get secondary infection from broken skin with candida, bacteria (staph or strep)
Presentation:
- Sore, red skin in the nappy area (sparing skin creases)
- Itchy and the infant may be distressed
Management:
- Maximise time without nappy
- Change nappy and clean skin as soon as possible after wetting/soiling, ensure is dry before replacing nappy
- Change nappies to highly absorbent
- Treat any additional infections e.g. antifungals or antibiotics
State some risk factors for the development of nappy rash (contact dermatitis)
Non-modifiable:
- Pre-term babies
Modifiable:
- Delayed nappy changing
- Poorly absorbent nappies
- Episodes of diarrhoea
- Irritant soap products
- Vigorous cleaning
- Oral antibiotics (higher risk of candida)
State what features would make you suspect an additional candida infection, on top of nappy rash
- Rash involves skin creases
- Larger red macules
- Well demarcated scaly border
- Rash appears circular in natures (similar to ringworm)
- Satellite lesions (small lesions associated with main lesions)
Head lice - state the following:
- Pathophysiology
- Presentation
- Management
Pathophysiology:
- Infection of the scalp with pediculus humanus capitis parasites
- Most common in school aged children
- Spread by close contact with someone else with head lice, either direct head to head contact or by sharing coombs/towels
Presentation:
- Itchy scalp
- Often nits (eggs) and lice are visible on scalp
Management:
- NICE recommend The Bug Buster Kit
- Wet combing = systematic combing of wet hair with special detection comb to remove head lice
- Dimeticone 4% lotion = 8 hours overnight and washed off
- Children who are being treated for head lice can still attend school
- No need to wash bedding etc. at high temperatures
Erythema nodosum - state the following:
- Pathophysiology
- Presentation
- Investigation
- Management
Pathophysiology:
- Hypersensitivity reaction of the subcutaneous fat layer on the shins
- Leads to erythematous lumps to present along the patient’s shins
- In 50% of patients, there is no identifiable cause
Presentation:
- Red, inflamed raised subcutaneous nodules along both shins
- Can be painful and tender
- Over time, will settle and appear as bruises
Investigation - aims at identifying underlying cause:
- Inflammatory markers e.g. CRP and ESR
- Throat swab (strep infection)
- Chest x-ray (atypical chest infections, sarcoidosis, lymphoma)
- Faecal calprotectin (IBD)
- Stool microscopy and culture (campylobacter / salmonella)
Management:
Main aim is identifying and treating the underlying cause
- Generally conservative management with rest and analgesia (steroids sometimes used)
- Most cases should resolve within 6 weeks
State some conditions associated with erythema nodosum
Chronic diseases:
- IBD
- Sarcoidosis
- Leukaemia / lymphoma
Acute conditions:
- Strep throat infections
- Gastroenteritis
- TB / mycoplasma pneumoniae
- Pregnancy
- Certain medications e.g. COCP
Staphylococcal scalded skin syndrome (SSSS) - state the following:
- Pathophysiology
- Presentation
- Management
Pathophysiology:
- Caused by a type of staph aureus bacteria which produces epidermolytic toxins (protease enzymes break down skin proteins)
- Causes skin to break down
- Typically occurs in children < 5 year (older have developed immunity)
Presentation:
- Starts with generalised erythematous patches on skin, skin looks thin and wrinkled
- Bullae form, which burst and leave very sore erythematous skin (looks like a burn/scalding)
- Positive Nikolsky sign (gentle rubbing will remove layers of skin)
- Systemic symptoms of fever, irritability, lethargy and dehydration
Management:
- Admission to hospital for IV antibiotics
- Ensure well dehydrated with IV fluids and fluid monitoring
- With correct treatment, most children should recover without scarring
Steven-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) - state the following:
- Pathophysiology
- Presentation
- Management
Pathophysiology:
- SJS and TEN are the same pathology but are on a spectrum
- Disproportional immune reaction leading to epidermal necrosis
- This results in blistering and shedding of the top layer of the skin
- Steven-Johnson syndrome affects < 10% and toxic epidermal necrolysis affects > 10% and is more severe
Presentation:
Spectrum of symptoms depending on severity
- Start with non-specific symptoms of fever, cough, sore mouth, sore eyes, itchy skin
- Red / purple rash across body
- Then rash blisters and burst
Management:
Medical emergency
- Admitted to dermatology or burns unit
- Supportive care e.g. analgesia, fluids, nutrition
- Steroids, immunoglobulins or immunosuppressants
State some causes of Steven-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN)
- Medications
- Infections
Medications:
- NSAIDs
- Allopurinol
- Anti-epileptics
- Antibiotics
Infections:
- HIV
- HSV (herpes simplex virus)
- CMV
- Mycoplasma pneumoniae
Pityriasis Rosea - state the following:
- Pathophysiology
- Most common age
- Presentation
- Management
Pathophysiology:
- Generalised, self limiting rash with an UNKNOWN CAUSE
- May be caused by herpes virus 6 or 7 but no definitive organism known, but can often have viral respiratory illness preceeding rash
Most common age:
- Typically occurs in teenagers and young adults
Presentation:
- Prior to rash, prodromal symptoms e.g. fever, headache, tiredness
- Characteristic ‘herald’ patch, faint pink scaly oval lesion on the torso
- Then widespread pink scaly oval lesions on torso, ‘christmas tree’ pattern
Management:
- Rash should resolve without treatment in 3 months. Can leave discolouration but will resolve in a few more months
- Reassurance is needed, it is not contagious and they can continue activities
- May need some symptomatic treatments e.g. emollients or antihistamines
List some differentials for a child presenting with rash AND fever
- Meningococcal sepsis
- Measles
- Chicken pox
- Rubella
- Slapped cheek syndrome (Parvovirus B19)
- Hand, foot and mouth disease
- Scarlet fever
- Roseola
- Urticaria (hives)
