A brief overview of a dermatologic disorder Scabies, including its aetiology, diagnostic points, different subtypes and medical management.

1. 7th March, 2023
By:
AREEBA MUSTAFA
Karachi Medical and Dental College
SCABIES
A brief overview of
a Dermatologic infestation by Sarcoptes scabei

2. What is Scabies? Introduction and
Aetiology
How can we make a Diagnosis?
1
2
What does this presentation
include?
Scabies in children and Crusted
Scabies
Management Plans
3
4

3. Introduction &
Aetiology
The most common skin infestation
worldwide is Scabies
You can develop Scabies if your skin gets infested by a female parasitic mite, Sarcoptes scabiei, which burrows itself into the
epidermis, lays eggs, which hatch into larvae within a few days.
It is transmitted because of close personal contact (requiring at least 15 minutes of skin-to-skin contact) and symptoms
usually take around 2 weeks to appear.
As in most cases, your skin might carry 10 adult mites if you are an immunocompetent indiviual.
However, their number may reach to hundreds if you are immunocompromised and have developed 'crusted Scabies'

4. Diagnosis
1
2
3
4
5
Several indiviuals in the same household/institution/classroom
being affected simultaneously
Following key points in the history and examination
include:
A widespread papular rash, characteristically distributed on
the fingers, wrists, axilla, nipples, abdomen, genitalia, and
ankle.
Rash is intensely itchy AT NIGHT
BURROWS can be seen, especially in the finger-web spaces
and on the genitals.
Multiple excoriations marks, which can become secondarily
infected by Staphylococcus

5. Picture courtesy: Science Photo Library
Picture Courtesy: The Primary Care Dermatology
Society
There may be very few burrows
Though the patients have widespread itching

6. Scabies in Children
Babies and young children infested with
Scabies characteristically present with:
- Erythematous cutaneous NODULES and
papules in the AXILLAE and on the SOLES of the
feet.
- Lesions may BLISTER
- Classic burrows are uncommon
Picture Courtesy:
MedicineNet.com
Picture Courtesy:

7. Crusted Scabies
3
Very little
erythema (unlike
Psoriasis and
Eczema)
A form of Scabies found in immunosuppressed and erderly indiviuals
- Crusted Scabies look similar to
dry, scaly skin rashes such as
Psoriasis and Eczema.
- Lesions are characterized by
fine crusted scaling on the skin,
which is superficial.
- Mite numbers are usually in
hundreds.
Picture Courtesy:
MDAngle

8. Management:
A full explanation of how to use topical therapy
is essential since most common cause of
treatment failure is incorrect use of
insecticides.
Lotions should be applied from neck
downwards. (In children, apply to all the skin
including head)
Left on overnight.
Repeated after 7 days
Pay particular attention to genitals and finger-
web spaces.
Skin itching takes 6-8 weeks to subside.
Avoid scratching and overtreating the skin as
the risk of Irritant Dermatitis can arise.

9. References:
ABC Dermatology by Rachael Morris-jones
and NHS.com

10. Thank you! Have a great
day ahead.