Scabies

Question 1

What reaction is seen in scabies?

Answer 1

Delayed type IV hypersensitivity reaction to mites/eggs, occurs about 30 days after the initial infection.

Question 2

Clinical features of scabies?

Answer 2

1) widespread pruritus

2) linear burrows on the side of fingers, interdigital webs and flexor aspects of the wrist

3) in infants, the face and scalp may also be affected

4) 2ary features are seen due to scratching: excoriation, infection

Question 3

1st line mx of scabies?

Answer 3

Permethrin 5%

Question 4

2nd line mx of scabies?

Answer 4

Malathion 0.5%

Question 5

How long can pruritus persist up to post-eradication?

Answer 5

4-6 weeks

Question 6

Patient guidance on scabies treatment?

Answer 6

1) avoid close physical contact with others until treatment is complete

2) all household and close physical contacts should be treated at the same time, even if asymptomatic

3) launder, iron or tumble dry clothing, bedding, towels, etc., on the first day of treatment to kill off mites.

Question 7

How long after initial treatment should treatment be repeated in scabies?

Answer 7

7d later