Scabies Flashcards
What causes scabies?
The mite Sarcoptes scabiei
How is it spread?
Prolonged skin contact e.g by holding hands or sharing a bed
Who does it typically affect?
Children and young adults
What does the mite do?
It burrows into the skin, laying its eggs into the stratum corneum - the eggs hatch as larvae
What causes the intense pruritis?
A delayed type IV hypersensitivity reaction to mites/ eggs , which occurs about 30 days after the initial infection
What features are associated?
Widespread pruritis
A short, wavy grey or red line on skin surface
Papules, vesicles, pustules and nodules
The eruption is usually excoriated and becomes eczematised
What part of body does it typically affect?
Finger webs
Side of fingers
Wrist flexures
Axilla
Abdomen - around umbilicus and waistband
Buttocks
Groin - itchy red penile or scrotal papules are virtually diagnostic
In young infants what areas are characteristically involved?
Palms and soles
What general treatment advice should be given?
Avoid close physical contact with others until treatment complete
Wash all sheets, towels and clothing in hot wash on first day of treatment to kill off mites
How should it be managed?
Treat all members of household at same time even if asymptomatic
First line: permethrin 5% dermal cream
Second: malathion (not if pregnant)
Oral ivermectin if severe scabies
Anti pruritic cream - crotamiton
Take warm bath and soap skin all over
Scrub fingers and nails with brush and dry body
Apply treatment to all body parts - avoid eyes
Wash off after 24 hours
Repeat after 7 days
When is the itch worse?
At night
Where does the rash usually start first?
Between fingers
Crusted (Norwegian) scabies is seen in…
Patients with suppressed immunity, especially HIV
