Paeds - Dermatology Flashcards
what is impetigo?
superficial bacterial skin infection usually caused by staph aureus
characteristic appearence of impetigo?
golden crust
usually on the face
what causes impetigo?
usually staph aureus
can be strep pyogenes
should kids be kept off school with impetigo?
yes
v contagious
2 types of impetigo?
bullous
non-bullous
features of bullous impetigo?
staph produces epidermolytic toxins that break down proteins holding skin together causing 1-2cm fluid filled blisters to form on the skin
vesicles grow then burst forming a golden crust
lesions can be painful and itchy
may have some systemic symptoms of infection if v bad
does bullous impetigo leave scars?
no
who is bullous impetigo more common in?
neonates and kids under 2
but can occur in older kids and adults
how is bullous impetigo diagnosed?
swabs of vesicles
features of non-bullous impetigo?
usually occurs around nose and mouth
exudate from lesions forms golden crust
looks bad but doesnt cause systemic symptoms
how is non-bullous impetigo managed?
uncomplicated, not unwell or at risk of complications = topical hydrogen peroxide
if hydrogen peroxide unsuitable = topical antibiotic (fusidic acid) for 5 days
if widespread or severe can give oral fluclox
how is bullous impetigo managed?
oral antibiotics (fluclox)
what is molluscum contagiosum?
viral skin infection caused by molluscum contagiosum virus (Poxvirus)
characteristics of molluscum contagiosum?
small, flesh coloured papules (raised) which usually have a central dimple
typically appear in crops of multiple papules in a local area
how does molluscum contagiosum occur?
spread through direct contact or by sharing towels/bedsheets etc
course of molluscum contagiosum?
usually resolve without treatment but takes up to 18 months
skin returns to normal afterwards but should advise against picking/scratching them as it may cause scarring
how is molluscum contagiosum managed?
no real treatment needed
advise against sharing towels or close contact with the lesions etc
may need topical antibiotics if superficial bacterial infections occurs (eg from picking/scratching) but this is rare
what causes chickenpox?
varicella zoster
chickenpox rash features?
widespread erythematous raised vesicular blistering usually starts on trunk or face and spreads outwards affecting whole body over 2-5 days
is chickenpox contagious?
yes
once lesions have scabbed over though its not contagious
other symptoms of chickenpox?
fever often first symptom
itch
general fatigue and malaise
how is chickenpox spread?
direct contact with the lesions or infected droplets through cough/sneeze
when do chickenpox symptoms start?
10 days - 3 weeks after exposure
complications of chickenpox?
bacterial superinfection dehydration conjunctival lesions pneumonia encephalitis (presents as ataxia) reactivation
how does chickenpox reactivate?
virus lays dormant in sensory dorsal root ganglion cells and cranial nerves reactivate later in life as shingles or ramsey hunt syndrome
how is risk of chickenpox managed in pregnancy?
no risk if immune to chickenpox (already had it)
if not immune (never had it) then they are given varicella zoster immunoglobulins after exposure
what can chickenpox cause in pregnancy?
if before 28 weeks, can cause developmental problems in foetus (congenital varicella syndrome)
if around time of delivery can cause life-threatening neonatal infection
how is chickenpox around time of delivery managed?
varicella zoster immunoglobulins and aciclovir
how is chickenpox managed?
usually self limiting and needs no treatment
aciclovir sometimes used if immunocompromised, neonates or if over 14 and presenting within 24 hrs
itching can be helped with calamine lotion and antihistamines
what causes measles?
measles virus
spreads via resp droplets
symptoms of measles?
starts 10-12 days after exposure - fever - coryzal symptoms - conjunctivitis - koplik spots erythematous, macular rash with flat lesions starts on face (classically behind ears) 3-5 days after fever then spreads to rest of body
what are koplik spots?
greyish white spots on buccal mucosa
appear 2 days after fever
pathopneumonic for measles
how is measles managed?
usually self resolves after 7-10 days
kids should be isolated until 4 days after symptoms resolve
should be notified to public health
what causes scarlet fever?
group A strep (strep pyogenes)
caused by exotoxin produced
associated with tonsillitis
features of scarlet fever?
red/pink blotchy macular rash with rough sandpaper skin starts on trunk and spreads outwards can have red, flushed cheeks fever lethargy sore throat strawberry tongue cervical lymphadenopathy
how is scarlet fever managed?
antibiotics for the underlying strep infection (phenoxymethylpenicillin) for 10 days
should be reported to public health
keep kid off school until 24 hrs after starting antibiotics
other conditions associated with group A strep?
post-strep glomerulonephritis
acute rheumatic fever
how is rubella spread?
rubella virus spread by resp droplets
rubella symptoms?
symptoms start 2 weeks after exposure
- erythematous macular rash starting on face and spreading to rest of body
- rash usually lasts 3 days
- can be associated with mild fever, joint pain and a sore throat
- often have enlarged lymph nodes behind ears and back of neck
how is rubella managed?
self limiting
notify public health
stay off school for 5 days after rash appears
avoid pregnant women
complications of rubella?
thrombocytopaenia
encephalitis
congenital rubella syndrome in babies born to mother with rubella
signs of congenital rubella syndrome?
triad of deafness, blindness and congenital heart disease
other names for slapped cheek?
erythema infectiosum
parovirus B19
what causes slapped cheek?
parovirus B19
symptoms of slapped cheek?
starts with mild fever, coryza and non-specific viral symptoms (lethargy, muscle ache etc)
after 2-5 days the rash appears on the face then spreads to trunk and limbs after a few days
describe slapped cheek rash?
diffuse bright red rash on both cheeks appears rapidly a few days after viral symptoms
few days later a reticular, mildly erythematous rash on trunk and limbs, can be raised and itchy
what does reticular mean?
net-like
course of slapped cheek?
self limiting and rash/symptoms usually fade over 1-2 weeks
management of slapped cheek?
fluids and simple analgesia
self limiting
only infectious prior to rash forming so dont need to stay off school once rash has appeared
who is at risk of complications from slapped cheek?
imunocompromised
pregnant women
people with haematological conditions
how are high risk people managed after expsoure to parovirus B19
require serology testing to confirm parovirus B19
check FBC and reticulocyte count for aplastic anaemia
possible complications of slapped cheek?
aplastic anaemia
encephalitis or meningitis
pregnancy complications including foetal death
rarely hepatitis, myocarditis or nephritis
