Scabies Flashcards
How is scabies transmitted and by what bug?
It is transmitted by skin to skin contact an the mite sarcopies scab var ham inis
Are scabies transmitted transmitted on bed linen and clothing?
There is also suggestion that transmission can occur by clothing and bed linen, however the scabies does not survive off the skin
Once you have scabies on your skin, what do the bugs to next and what are the consequent symptoms?
The mite brows into the epidermis. The females poop and lay eggs causing irritation and itching.
What is characteristic about the itching secondary to scabies?
it is worse at night
What is the incubation period?
Three weeks.
Which areas of the body are most affected by the scabies and the itching?
the webs of the hands, flexor aspect of the wrist and elbows, axilla, male genitalia, woman’s breasts
How do you make a DEFINITIVE diagnosis?
skin scrapings - taken form the burrows and examined under a low power microscope
In infants the clinical manifestation can be different. How are they different?
Location: the lesions are usually concentrated on the hands and feet, as well as the body folds and scalps
appearance of lesions: they can look vesiculo-pustular
NB they can often be confused with impetigo or eczema
What are some risk factors for scabies?
- crowded population
- shared beds
- day care centres
- reduced access to health care
- treatment failure: faulty application, failure to treat contacts, failure to eradicate mites in bedlinen
What do you treat scabies with? (1st line)
And how do apply it?
Any special precautions in smaller children? (3)
5% permethrin applied to the WHOLE body (including the scalp)
wash off after 8-14 hours
repeat treatment 1-2 weeks later
- In children
How does primethrin work?
It disrupts sodium channel current resulting in delayed depolarisation, paralysis and death of the parasite
Mom “I got a medication to treat head lice, can I use it for scabies? I think it is the same medication.”
Head lice can be treated with 1% Permethrin, and this is not effective against scabies
What is the second line medication? And how do you use it?
Lindane cream
Wash it off after 6 hours in infants, 6-8 hours in children and 8-12 hours in adults.
Other than Lindane and permethrin, what are the other medications used?
Precipitated sulphur 7% in petroleum jelly - used in very young infants, pregnant and lactating women. It needs to be applied for three consecutive days and left on for 24 hours.
Do you need to treat the family?
yes. The infested patient, his or her family and any close contacts must be treated at the same time regardless of whether they have symptoms.
