Ch 3.3 - Cold Sores & Scabies Flashcards
Name the virus responsible for cold sores / herpes labialis
and which one typically infects the lips?
herpes simplex virus (HSV) of which there are two major types:
HSV1 and HSV2.
herpes simplex virus (HSV) of which there are two major types:
HSV1 and HSV2.
How do cold sores occur?
Initial infection usual at young age. The virus is not completely eradicated and virus particles lie dormant in nerve roots until they are reactivated later.
Describe the symptoms and timeline of cold sores
Discomfort, tingling or irritation (prodromal phase) may occur in the skin 6-24 hours before appearance.
Begins with minute blisters on top of inflamed, red, raised skin. Maybe filled with white matter.
Quickly break down to show raw area and crusts by 4th day.
About 1 week - most lesions healed
Extremely painful - critical to distinguish from mouth cancer
What are the precipitating factors of cold sores?
Sunlight Wind Fever (during infections & colds) Menstruation Being rundown Local trauma to skin Physical/Emotional stress
When should you refer patients with cold sores?
- Babies and young children
- Failure of a sore to resolve
- Severe or worsening sore
- History of freq. sores
- Lasting longer than 2 weeks
- Painless sore
- Patients with atopic eczema
- Eye affected
- Uncertain diagnosis
- Immunocompromised patient
What can be used to treat a cold sore?
- Aciclovir (antiviral) - reduces healing time and pain
Treatment should be started asap before lesion appears (most effective). - Antiseptics
Complementary therapies: tea tree oil & balm mint extract
How often should Aciclovir be used?
5 times a day up to 5 days.
What are some practical points to prevent cold sores?
Preventing cross infection - HSV1 is contagious and transmitted by direct contact.
Use of sunscreen
Sources of stress identified
What is scabies?
Infestation by the scabies mite (Sarcoptes Scabei)
What are the symptoms of scabies?
Causes an allergic reaction - Intense itching especially at night
Burrows can be seen like small thread-like grey lines. Lines are raised, wavy and 5-10mm long.
Rash - but not always at the site of infestation
Where do you usually find the burrows of scabies?
Web spaces of hands and toes, wrists, armpits, buttocks and genital area
In adults - rarely affects the scalp and face but in children aged 2 or under and elderly, the head is more common
How long does it take for an itch to develop in someone who has not been infested before?
6-8 weeks
Scabies mite transmitted by close personal contact - so ask patient if any close family/friends/boy/girlfriends have the same symptoms
What can scratching lead to in scabies?
Leads to excoriation = secondary infection such as impetigo can occur
presence of yellow discharge or crusts = referral
When should you refer patients with scabies?
- Babies and scabies
- Infected skin
- Treatment failure
- Unclear diagnosis
Treatment for scabies?
- Permethrin cream
- Malathion used if above not suitable
Two treatments recommended - 7 days apart
How would you counsel a patient on how Permethrin cream is to be used?
30-60g for single application in an adult. Treatment applied to the whole body, neckwards down (but not neck, face and scalp in adults)
Preparation should be emptied in a bowel, and using a paintbrush or cotton wool, it should be applied to clean, dry skin all over the body as directed. Ensure webs of fingers, fingernails and toenails are covered too.
Left for 8-12 hours
How would you counsel a patient on Malathion?
for 1 adult - 100ml should be sufficient.
Applied to the whole body omitting the head and neck. Lotion should be left on for 24 hrs, without bathing, after which should be washed off.
If hands washed during the 24 hours - it should be reapplied to hands.
Itch will continue after treatment with scabies creams - what can be advised?
Crotamiton cream/lotion could be used to relieve symptoms if skin is not badly excoriated.
Oral antihistamines - promethazine if itch is severe
What are some practical advice for scabies?
Apply cream at bedtime - leave to dry first.
apply to clean, cool and dry skin
All members of family/household should be treated on the same day
Bedclothes and clothing should be washed
