Paediatrics: Dermatology + Allergy Flashcards
What is eczema ? defect with what ?
chronic atopic condition caused by defects in normal continuity of skin barrier => inflam of the skin (Sx can rly vary)
eczema presentation ? located where ?
usually in infancy
- dry, red, itchy + sore patches
- on flexor surfaces (inside of elbows + knees) and face + neck
- periods where it is well controlled + then periods when worse (flares)
eczema pathophys ?
Defects in barrier that skin provides => tiny gaps => entrance for irritants/microbes/allergens => immune response => inflam
eczema overall Mx ?
maintenance + Mx of flares
desceirb eczema maintenance Mx ?
create arterial barrier over skin to compensate for defective one (emollient)
- avoid scratching/scrubbing skin, harsh soaps
eczema flares Mx ?
- use thicker emollients
- wet wraps
- topical steroids
describe the emolients used in eczema Mx ? examples ?
use as thick as tolerated to maintain healthy skin
- thin creams (E45)
- thick greasy (50:50)
describe the use of topical steroids in eczema Mx ? examples ?
use weakest steroid for shortest period
- mild (hydrocortisone)
- v potent (dermovate)
how does eczema increase risk of bacterial infection ? what is most common causative organism ? how managed ?
skin barrier breakdown => entry point for infective organism (s.aureus)
- Mx: oral Abx (flucloxacillin)
What is Eczema herpeticum ? causative organism ?
viral skin infection in patients with eczema caused by HSV (most common) or VZV
patient with eczema has developed widespread, painful, vesicular rash. what is this ? what other Sx associated ?
eczema herpeticum
- plus systemic Sx: fever, lethargy, irritability, reduced oral intake, lymphadenopathy
eczema herpeticum Mx ?
viral swab of vesicles
- Aciclovir (HSV1 most common causative organism)
complications of eczema herpeticum ?
children can be v unwell
- bacterial super infection => more severe illness
What is psoriasis ?
chronic autoimmune ocnditon => recurrent Sx of psoriatic skin lesions
describe patches of psoriasis ? located where ?
dry, flakey, rough, faintly erythematous lesions
- usually extensors surfaces 9elbows, knees), scalps
what causes psoriatic lesions ?
caused by rapid generation of new cells => abnormal buildup + skin thickening
what are the different types of psoriasis ? most common in adults ? most common in kids ?
- Plaque psoriasis (most common type in adults)
- guttate (common in kids)
- Pustular (rare and severe)
describe plaque psoriasis ?
thicken erythematous plaques with silver scales
(most common type in adults)
describe guttate psoriasis ? often associated with what ?
common in kids
- many small raised pauses across trunk + limbs (slightly scaled) (can turn into plaques)
- often triggered by throat infection
what Ix for psoriasis ?
clinical appearance of lesions is diagnostic
psoriasis Mx ? (2)
- topical steroids
- topical vit D analogues
name some associations of psoriasis ? (complications) (3)
- nail psoriasis: pitting, thickening, discolouration, onycholysis
- psoriatic arthritis (10-20%)
- psychosocial
what is acne vulgarisms ? common when ?
extreme common condition during puberty + adolescence (can vary from mild - severe)
acne pathophys ? increased production of what ?
caused by chronic inflam +/- local infeciton
- acne results form increase production of sebum, trapping of keratin + blocking of pilosebavious unit => swelling + inflam of pilsebacious unit (comedones)
acne Px ? (5)
- macules
- papules
- pustules
- comedones (inflamed pilsebacious unit)
- blackheads
acne Mx ?
- topical benzyl peroxide
- topical retinoids
- topical Abx
- OCP
what is the last line acne management ? how does it work ? SE ? (3)
oral retinoids (isthtinoin): reduce seem, reduce inflam and reduce bacterial growth
- SE: teratogenic, photosensitivity, depression (+suicidal ideation), stevens Johnson sydnrome
What is erythema multiforme? common cause ?
erythematous rash caused by hypersensitivity reaction
- common cause: viral infection (HSV or mycoplasma pneoumia)e
erythema multiform Px ?
widespread itchy erythematous rash + characters target lesions
- stomatitis
erythema multiform Mx ?
clinic Dx
- usually mild and resolves within 1-4 weeks
What is urticaria ? describe appearance ?
(aka hives)
- small itchy lumps that appear in skin +/- patchy erythematous rash
- may be a associated with angioedema + flushing of skin
urticaria pathophys?
release of histamine + other pro inflam chemicals
acute urticaria causes ? aetiology ?
acute: (something that triggers mast cells => histamine release)
- allergies to food/medications/animals
- viral infeciton
- insect bite
chronic urticaria causes ? aetiology ?
chronic (autoimmune - Ab target mast cells => histamine release from mast cells)
urticaria Mx ?
antihistamines (fexofenadine)
- severe flare: oral steroids
What is seborrhoea dermatitis ? affecting what ? affecting where ?
inflam condition affecting the sebaceous glands (oil producing gland in skin)
- affects places with lots of these glands (scalp, nasolabial folds, eyebrows)
how dos seborrhoea dermatitis present in infants ? AKA ?
infants => often crusted, dry scalp => aka cradle cap
cradle cap Mx ?
(seborrhoeaic dermatitis)
- self limiting + resolves in about 4 months
- Mx: apply vegetable of olive oil
What is ring worm ? most comm causative organism ? how spread ?
fungal infection of the skin (general)
- most common type of fungus causing ring own (trichophyton)
- spread through contract with infected individuals
ringworm Px ? describe the rash ? where look especially ?
- itchy rash, erythematous, clay + well demarcated
- often on or several signs of circular shaped areas (well demarcated)
- check toenails (thickened, discoloured + deformed nails)
ringworm management ?
anti fungal medications (creams, shampoo, oral): clotrimazole
What is nappy rash ? caused by ?
contact dermatitis in the nappy area
- caused by friction between skin + nappy and contact with urine + faeces
nappy rash RF ?
- delayed aching of nappies
- irritant soaps
- vigorous cleaning
- preterm
nappy rash Px ? what rash like ?
sore, red + inflamed skin in nappy region (may spare the skin creases)
nappy rash similar rash that spreads to skin folds. consider what ? check where else /
more likely candida infection
- look for oral thrush
nappy rash Mx ?
change nappy and clean asa; after wetting/soiling,
- maximise time without nappy
Nappy rash complicaitons ?
- candida infeciton
- cellulitis
What is scabies ? causative organism ? overall sx ?
tiny mites (Sarcoptes scabiei) that burrow under skin => infection + intense itching
- lay eggs in skin => further infection + sx
scabies Px ? describe rash ? location ?
incredible itchy small red spots + track makes where mites have borrowed
- often between finer webs
scabies Mx ? describe the treatment regime
pernitrim cream (to whole body), left on for 8-12 hours)
- then washed off
- repeat 1 week later
- v contagious so treat all household members the same
- stay off work/school until 24hrs after first treatment
what is crusted scabies ?
serious infection in immunocomprosmes patient
- may need admission for treatment (oral ivervectin + isolation)
how are headline transmitted ?
transmission is by head to head contract of sharing equipment (hairbrush, towel)
headlice Mx ?
diameticone applied to wet hair + left to dry (repeated 7 days later)
- special fine combs
- no need to stay off school
What is erythema nodosum ? often associated with what ? (3)
condition where red lumps appear across patients kin
- often indicated IBD or sarcoidosis or strep throat
erythema nodosum Ix ?
looking for underlying cause
- inflam markers (IBD, sarcoidosis)
- throat swab (strep throat)
- faecal calprotectin (IBD)
What is impetigo ? caused by what ? transmission ?
superficial skin infection usually caused by s. aureus
- contagious and kids should be kept off school
-occurs when bacteria enter via a break in the skin
what are the two types of impetigo ?
- non-bullous
- bullous
where does non-bulbous typically affect ? presentation ?
typically around mouth/nose
- exudate form lesions dry => golden crust
non bullous impetigo Mx ? if widespread ?
topical fusidic acid, oral flucloxacillin (if widespread)
what is bullous impetigo ? what is the causative organism ? explain
always s.aureus
- epidermolytic toxins + breakdown proteins that hold skin otgheter => fluid filled vesicles on skin => grow + burst => golden crust
what happens when bullous impetigo is widespread ?
can go to staphylococcus scalded skin syndrome
bullous impetigo Mx ?
flucloxacillin
- v contagious so should be isolated where possible
What is stenes=johnsons syndrome and toxic epidermal necrolysis ? causing what ?
they are a spectrum of the same pathology: disproportional immune response => epidermal necrolysis => blistering and shedding of top layer of skin
causes of SJS + TEN ? (2)
- Meds (anti-epileptics, Abx, NSAIDs)
- infections (HSV)
SJS + TEN Px ? (7)
can be mild or severe/life threatening
- fever, cough, sore throat, sore eyes, itchy skin
- then purple red rash: that starts to blister => skin breakdown and shed
SJS + TEN Mx ?
- steroids
- immunoglobbulins
- immunosepressants
SJS + TEN complications ?
- secondary infection (due to breaks in skin)
- permanent skin damage
- visual complications (blindness)
What is an allergy ? response to what ? causing what ?
hypersensitivity of the immune system to allergens (proteins that the immune system recognises as foreign => allergic immune reaction)
What is Atopy ? associated with what conditions ?
predisposition to having hypersensitivity reactions to allergens
- tendency to develop: eczema, asthma, allergic rhinitis + food allergies
- tends to run in families and likely to come together
What is the skin sensitisation theory ? what does it relate to/explain ?
origin of allergies
- there is break in infants skin (eczema or infection) that allows allergens to enter PLUS
- child does not the contact with allergen in GI tract
what is a type 1 hypersensitivity reaction ? what cell/type involved ? explain it ? give condition examples ?
IgE antibodies to specific allergen => mast cells + basophils release histamines + cytokines => immediate reaction
- anaphylaxis, urticaria, allergic rhinitis
what is a type 2 hypersensitivity reaction ? what cell/type involved ? explain it ? give condition examples ?
IgG + IgM react to allergen => complement system activation => direct damage to local cells
- haemolytic disease of the newborn, transfusion reaction
what is a type 3 hypersensitivity reaction ? what cell/type involved ? explain it ? give condition examples ?
Immune complexes accumulate => damage to local tissue
- SLE, RA, HSP
what is a type 4 hypersensitivity reaction ? what cell/type involved ? explain it ? give condition examples ?
cell mediated caused by T lymphocytes
- organ transplants reaction, contact dermatitis
Ix for allergies ? gold standard ?
- skin prick
- food challenge testing (gold standard)
what does a skin prick test test for ?
assess sensitisation not allergy
What is allergic rhinitis ? what type of hypersensitivity ? explain a bit
IgE medicated type 1 hypersensitivity reaciton
- environment allergens => allergic inflam response in nasal mucosa
allergic rhinitis Px ? (3)
- runny, blocked + itchy nose, sneezing,
- itchy/red eyes
- associated with personal or FHx of atopy
allergic rhinitis Mx ?
- avoid triggers (hoover + change pillows + good ventilation)
- oral antihistamines: loratedine
- nasal antihistamines: in response to a trigger
What is a normal amount of resp infection for healthy child per year
up to 4-8
when would you consider Ix for recurrent infection in children ? (3)
- chronic diarhoea since infancy
- FTT
- unusual/persistnat infections
What is severe combined immunodeficiency syndrome ?
most severe condition causing immunodeficiency: children have almost no immunity
would causes severe combined immunodeficiency syndrome ? aetiology ?
- multiple genetic disorders => absent of dtysfunctioning T + B cells
severe combined immunodeficiency syndrome Px ? (3) what age ?
usually present in first few months with:
- persisten diarrhoea
- FTT
- unwell after live vaccinations
severe combined immunodeficiency syndrome Mx
- treat underlying infecitons
- immunoglobulin therapy
- sterile environment
- Avoid live vaccines
- Haematopoetic stem cell transplantation
