Skin infections and infestations Flashcards
which bacteria causes toxic shock syndrome in women using tampons
staph aureus
how does a staph aureus skin infection present
rash
peeling skin
impetigo (blistering skin infection, yellow crusting)
staphylococcal scalded skin syndrome (SSSS)
vomiting
diarrhoea
how can staph aureus infect the skin
via hair follicles = folliculitis
entering broken skin in eczema
how does staphylococcal scalded skin syndrome (SSSS) occur
toxin produced by staph aureus
where does staphylococcal scalded skin syndrome (SSSS) occur
face, axilla, groin
what investigations would you do if a skin infection is suspected (any skin infection)
blood cultures
swab lesion if broken
which infecting organism (and condition) is associated with yellow/honey/gold crusting
staph aureus causing impetigo
how is a staph aureus skin infection treated
flucloxacillin (topical or PO)
what is a complication of a staph aureus skin infection
toxic shock syndrome (TSS think tampons!) - causes organ failure
how does a strep pyogenes (group A strep) skin infection present
impetigo
cellulitis
necrotising fasciitis
red blistering skin
how does necrotising fasciitis present
small rash but patient is in excruciating pain
crepitations on xray
feels like bubble wrap
how is a strep pyogenes (group A strep) skin infection treated
penicillin or flucloxacillin
what is a complication of a strep pyogenes (group A strep) infection
toxic shock LIKE syndrome (TSLS) - causes organ failure
what type of infection is ringworm
fungal
what is another name for ringworm
tinea
how is ringworm transmitted
usually human to human contact
enters ‘soggy’ skin
why is it called ‘ringworm’
lesion grows outwards = ring appearance
where is tinea capitis
scalp
where is tinea barbae
beard
where is tinea corporis
body
where is tinea munuum
hand
where is tinea unguium
nail
where is tinea pedia
foot aka athletes foot
where is tinea cruris
groin
what is the treatment of all ringworm (tinea) infections
clotrimazole cream
where does a candida skin infection present
in folds of skin eg under breast, groin, nappy area
treatment of candida skin infection
clotrimazole cream, fluconazole PO
which virus causes chicken pox
varicella zoster virus
which virus causes shingles
varicella zoster virus
which age group presents with chicken pox
children
how does chicken pox present
generalised fever and rash
red macular spots
itchy
location - more dense on trunk
what is ophthalmic zoster
chicken pox when the trigeminal nerve is affected
what happens after a patient has experienced chicken pox after an exposure to varicella zoster virus
virus remains in nerve roots of spine as a latent virus (no symptoms as latent)
what is the treatment for chicken pox
no treatment, just prevention with live attenuated vaccination
what is a rare complication of chicken pox
ramsay hunt syndrome (aka optic herpes zoster) when pain in auditory canal, deafness
which age group does shingles present in
elderly (with childhood chicken pox)
how does shingles occur
varicella zoster virus reactivation
how does shingles present (+location)
dermatomal location (as the virus is only in one nerve root)
neuropathic itch (damage to CNS)
sharp pain
rash - presents later than the pain/itch/tingling
facial involvement = ophthalmic zoster (naso ciliary branch oftrigeminal nerve affected)
what is the treatment of shingles
acyclovir
what is recurrent shingles a sign of
immunocompromised, check for HIV
how can shingles be prevented
live attenuated vaccine for >70s that haven’t had shingles yet
what age group does herpes simplex virus (type 1) affect (primary infection)
pre school aged children
how does herpes simplex virus (type 1) present
symptomless
mouth ulcers
erythema multiforme (target lesions)
can herpes simplex virus spread
yes it can spread to other parts of body, healthcare professionals (eg dentists)
how is herpes simplex virus (type 1) treated
acyclovir
what age group does molluscum contagiosum affect
children and adults
how is molluscum contagiosum transmitted
sexually
mother to child
how does a molluscum contagiosum infection present (3)
fleshy firm umbilicated papules
look fluid filled but are solid
1-2mm (small)
treatment of molluscum contagiosum
self limiting - takes <2 years
liquid nitrogen
what virus causes warts
HPV (human papilloma virus)
which age group are warts common in
children
what are warts on the feet called (plantar warts)
verrucas
treatment of warts/verrucas (2)
self limiting
FIRST LINE - topical salicylic acid OTC
SECOND LINE - liquid nitrogen (cryotherapy)
what is the presentation of a human papilloma virus (HPV) infection
warts - including verrucas, genital warts
cervical cancer
head and neck cancer
how can human papilloma virus infection be avoided
HPV vaccination in adolescence
what age group does herpangina affect
preschool children
what viruses cause herpangina
coxsackie virus
how does herpangina present (2) associated symptoms (1)
back of mouth/soft palate = loss of appetite
blistering rash
complicartions of herpangina
hand foot and mouth disease
treatment of herpangina
self limiting
what is another name for erythema infectiosum
slap cheek disease
what is the cause of erythema infectiosum
parvovirus B19
how does erythema infectiosum present (+location)
raised red rash
location - face an proximal limbs
complications of erythema infectiosum (in adults) (2)
spontaneous abortion
chronic anaemia
which group of patients does orf present in
farmers of sheep
presentation of orf
fleshy nodule on hands
treatment of orf
self limiting
how is syphilis transmitted
sexually
how does syphilis present
primary infection - painless ulcer at site of entrance (oral or genital)
OR
secondary infection all over body (hands and feet), ‘snail tract’ ulcers in mucous membrane
diagnosis of syphilis
blood tests
treatment of syphilis
IV penicillin
which skin infection presents with a large asymmetrical lesions with demarcated edges and a light centre
tuberculoid leprosy
what is another name for tuberculoid leprosy
hansens disease
what causes tuberculoid leprosy
mycobacterium
what is the cause of lyme disease
bacterial infection transmitted by ticks
how does lyme disease present
‘target/bullsesye lesion’ at site of bite
aka ‘erythema migrans’
complications of lyme disease
heart block
nerve palsy
diagnosis of lyme disease
blood test for antibody
treatment of lyme disease
doxycycline
amoxicillin 2nd line
how is zika virus transmitted (2)
mosquito
sexually
what is a complication of zika virus
guillain barre syndrome
what is pediculus capitus
headlouse
what is pediculus corporis
body louse
what is phthirus pubis
pubic louse
how are lice treated
malathion lotion
how does lice present
intense itch
how does scabies present (+location)
intense itch
rash in lines
location - gential, finger webs, back, wrist
treatment of scabies
malathion lotion
benzyl benzoate
what are Norwegian scabies
scabies with chronic crusting
why might PPE be needed in treating scabies
if it is Norwegian scabies
how does hand foot and mouth disease present
blistering in soles of feet, palms of hands and in the mouth
how is erythema infectiosum (slap cheek disease) treated
self limiting
what is the cause of scarlet fever
strep infection
how does scarlet fever present (3)
red rash - on trunk, cheeks, limbs
white coating on tongue
‘strawberry’ tongue - red and swollen
how is scarlet fever treated
penicillin
what do plantar warts (verrucas) look like
squashed warts, like a cauliflower
what happens when latent herpes simplex virus 1 reactivates
coldsores
what can reactivate herpes simplex virus type 1 (2)
hormones - stress, menstruation
what can happen in the brain in someone with latent herpes simplex virus type 1
temporal lobe necrosis (herpes simplex encephalitis)
which bacteria can cause gas to form in the tissues it infects
what is this condition called
group A strep (strep pyogenes)
necrotising fasciitis
treatment of necrotising fasciitis
surgical debridement
antibiotics - penicillin
which branch of which division of which nerve is affected in shingles when there is facial involvement
nasociliary branch of ophthalmic division of facial nerve
which cytotoxin does MRSA produce in necrotising fasciitis
panton valentine leucocidin (PVL)
