6 Flashcards
Epidemiology of skin disease
Skin disease in general:
15% of GP consultations are skin related
6% of hospital out patient attendances are skin related
In Europe
- 1% of population is referred to a dermatologist per year
-20% of population have a skin disease requiring medical intervention
Skin infections:
- High rates in hot humid conditions and poor populations
- Low rates in dry temperate conditions and rich populations
UK
- 25% of GP skin consultations
- 5% of dermatologist consultations
Toxins made by Staph aureus
- Panton Valentine Leuocidin
- Exfoliative toxin (causes blisters)
- TSST-1 (Toxic Shock Syndrome Toxin 1) - septicaemia symptoms
- Enterotoxin (causes diarrhoea when food is contaminated)
Toxins made by Staph aureus
- Panton Valentine Leuocidin
- Exfoliative toxin (causes blisters)
- TSST-1 (Toxic Shock Syndrome Toxin 1) - septicaemia symptoms
- Enterotoxin (causes diarrhoea when food is contaminated)
Manifestations of S. Aureus Skin Infections
Top layer: causes Impetigo
Epidermis: ecthyma
Follicullitis can cause aa boil and if mutliple boils are connected its aa caarbuncle
Impetigo
- honey coloured, crusted infection
- common in children, young people
- especially around nose and mouth
- quite contagious
Gold, crusty infection - what is it?
sounds like a staph aureus infection - impetigo
Bullous impetigo
- pus within blisters
Ecthyma
- crusted thick lesion
- read more
Abscess
-
Staphylococcal scalded skin syndrome
- in children mainly
- treated by admission to hospital
- antibiotics
- superficial dissimation
How does staph aureus present? How do you diagnose it?
variety of presentations
swab -> 48h
How do you treat it?
methicillin
if resistant it is an MRSA infection
Treponema pallidum
Gram negative spirochaete Cause of Syphilis Sexually transmited disease 12 million new cases per year worldwide Increases transmission of HIV
Syphilis phases
Primary (at 3-8 weeks)
Painless ulcer at inoculation site (Genital or oral)
Secondary (at 6-12 weeks)
Disseminated infection
Generalised rash and lymphadenopathy
Latent syphilis (no clinical signs)
Tertiary syphilis (usually years later) Skin, neurological and vascular manifestations
Congenital
Acquired perinatally
Early and late manifestations
Diagnosis of syphilis
primary:
Dark field microscopy of sample from a chancre
Demonstrates spirochates
Presentation of secondary syphilis
Maculopapular rash (can be widespread or some areas) Palm and soles involved Condyloma lata (perianal region)
rash cannot be seen under red light (brothels ;) )
Tertiary syphillis
- bone lesions
- thoracic aneurysm
- Gummatous skin lesions
- neurosyphilis
Neurosyphilis
- used to be the commonest cause of dementia
- Lenin died of syphilis
Congenital syphilis
Miscarriage Still birth Prematurity Rashes Brain and neurological problems (tertiary syphilis) Bone disease
blindness, skin bony lesions, abnormal teeth
Treatment of syphilis
ABs
penicillin?
Human Herpes virus family
- DNA viruses
HHV1 - oro genial herpes
HHV2 - oro genital herpes
HHV3 - chicken pox, shingles
all 3 remain latent in nerves
HHV4 - EBV infectious mononucleosis infecting B-cells
HHV5 - CMV
HHV6 - Roseola
HHV8 - Kaposis sarcoma
herpes simplex
HHV1 (mouth) and HHV2 (genital) -> however can also occur elsewhere
painful vesicular rash heals in about 2w usually no scarring eczema herpeticum herpes encephalitis
first outbreak may cause whole mouth inflammation (stomatitis)
Eczema herpeticum
- i.v. acyclovir treatment
-
border between skin and lip
vermilion border
Eczema herpeticum
- i.v. acyclovir treatment
- czema herpeticum is a disseminated viral infection characterised by fever and clusters of itchy blisters or punched-out erosions. It is most often seen as a complication of atopic dermatitis/eczema.
Varicella zoster
= chicken pox
- in children it is relatively mild
- in older children or adults can be severe
- incubation period of a week
- starts with malaise, fever then the rash comes, most concentrated on face, body, trunk, less on arms and legs
- can be in mouth
- gets better but lives in dorsal root ganglion
- can become bullous with blistering
FEEL UNWELL + HAVE A SPECIFIC RASH
Herpes diagnosis
- swab
- PCR
- results
tell patients that it can come back recurrently, treat with acyclovir.
Severe dangerous varicella zoster
- can cause encephalitis
- can cause pneumonia, especially in the elderly
- mortality rate for an old person is high
varicella zoster - where is it in the latent state?
- dorsal root ganglion
- when reactivated the rash is covering a dermatome
Facial herpes zoster
- if in trigeminal nerve
- can cause ophthalmicc herpes zoster
- painful, blindness, chronic facial pain
=> patients (70 yo) should have a shingles vaccine
Superficial skin fungal infections
Dermatophytes (type of mould)
eg Trichophyton rubrum
Grow in keratin
Long hyphae, grow from tip
Yeasts
eg Candida
Grow on warm wet surfaces
single cell and bud
Tinea unguium
- nail fungus
nails become yellow and crumbly
Tinea capitis
- affects scalp
- almost always pre-pubertal children
- post puberty no more susceptible
- can be wide spread or local
Kerion
(Type of tinea capitis)
cluster? local tinea capitis
Tinea manuum
fungal infection of hands
Tinea pedis
fungal infection of feet
tinea cruris
- means scrotum but scrotum is not infected
- fungus in the groin region
tinea facei
- fungal infection of the face
candida intertrigo
- yeasts like hot sweaty environments
- satellite regions arounnd
- take scrapings, cliipings or plucking and send away to be vulture.
- if too deep, cream is not enough and you need taablets
- candida usually reponds to clotrimazole
Scabies
- sarcoptes scabei
- female burrows into the skin and lays eggs
- burrows are within the stratum corneum, top layer of epidermis
- patient might scratch
Which sites to look scabies for?
4-5 mm
s shaped or squiggly line
black dot is the mite
look very carefully in certain sites for this!
you can use a dermatoscope you can see it in more detail
armpits around genital area (inflammatory bumps rather than burrows) cubital fossa waist wrist between fingers
after 4w itchy rash over the entire body looking like eczema, allergy associated with scabies
How do you treat scabies?
- cream, leave on for 12h then wash off
- do this for 5d
- change bedding
- change clothes
transmission is from skin to skin contact (many minutes are required e.g. in bed together)
Permethrin 5% cream is usually recommended as the first treatment. Malathion 0.5% lotion is used if permethrin is ineffective.
can cause glomerulonephritis in the 3rd world causes renal failure
