Viral Skin Infections Flashcards
(31 cards)
What is erythema multiforme
A hypersensitivity reaction, most commonly triggered by viruses
Causes of erythema multiforme
Infections - HSV Bacteria - mycoplasma pneumoniae, Streptococcus Idiopathic CTD Sarcoidosis Malignancy Drugs
What drugs can cause erythema multiforme
sulphonamides, penicillins, phenytoin, allopurinol, carbamazepine, NSAIDs, OCP
Presentation of erythema multiforme
Target lesions with erythema
Initially on back of hands and feet
Spreads to torso
Mild itch
Tx of erythema multiforme
Topical emollient + TCS or OCS
+ anti-virals if HSV cause
What is molluscum contagiosum
a common viral skin lesion seen in childhood
Presentation of molluscum contagiosum
multiple small pink papules with central dimple
look fluid filled but are solid
Koebner’s phenomenon - lesions are seen at the site of injuries
Tx of molluscum contagiosum
No Tx - self limiting and will resolve spontaneously
- Curettage
Virus causing chicken pox
Varicella Zoster virus
Presentation of chicken pox
Crops of blisters that follow :
macules - papules - vesicles - scabs - recovery
Generalised rash and fever
Itch
Tx of chickenpox
low risk of severe disease: supportive care (paracetamol etc)
higher risk of severe disease: oral antivirals (aciclovir)
Complications of chickenpox
secondary bacterial infection
pneumonitis - inflammation of the alveoli walls “varicella pneumonia”
haemorrhage
encephalitis
Virus causing Shingles
Varicella Zoster (aka Herpes Zoster)
The virus causing Chickenpox and Shingles is the same, so how do they present differently?
Shingles is reactivation of Chickenpox that occurs in later life
Presentation of shingles
Dermatomal distribution of lesions
Tingling pain - erythema - vesicles - crusts
What is Ramsay Hunt Syndrome
a complication of shingles where there is:
- vesicles and pain the auditory canal and throat
- 7th cranial nerve palsy
- irritation of CN 8 (deafness, tinnitus, vertigo)
Tx of shingles
Aciclovir
What is the cause of warts?
Human Papilloma Virus within keratinocytes
HPV types causing genital warts
6 and 11
HPV types causing cervical Ca
16 and 18
Tx of warts
wait and see - often resolve spontaneously
topical salicylic acid for at least 3 months
cryotherapy
What is herpangina
blistering rash at the back of the mouth
cause of herpangina
enterovirus
Tx of herpangina
self-limiting - tends to resolve within 7 days
