Chicken pox and shingles Flashcards
What pathogen causes chickenpox?
Varicella zoster virus
What is the incubation period of chicken pox?
10-21 days
How is chicken pox spread?
Via the respiratory route
In immunocompromised patients and newborns with peripartum exposure, what would you give to prevent the risk of developing chickenpox?
Varicella zoster immunoglobulin.
If chickenpox does develop, give IV aciclovir
What are some rare complications of chickenpox?
Pneumonia
Encephalitis (cerebellar involvement may be seen)
Disseminated haemorrhagic chickenpox
arthritis, nephritis and pancreatitis may very rarely be seen
What may increase the risk of severe bacterial infections if a patient has chickenpox?
Using NSAIDs
What do you give to the mothers around the time of delivery who have chickenpox?
Varicella zoster immunoglobulins and aciclovir
When pts have chickenpox, what cohorts of people should be considered for being given aciclovir?
Immunocompromised pts,pregnant women,adults,adolsescents over the age of 14 presenting within 24 hrs,neonates or those at risk of complications
What would you use to relieve the symptoms of itching when a pt has chickenpox?
Calamine lotion and chlorphenamine (antihistamine)
How long should pts wait to interact with society when they have chickenpox?
Until the lesions are dry and crusted (usually around 5 days after the rash appears)
What causes shingles?
Following primary infection with chickenpox, the virus lives dormant in the dorsal root ganglion/cranial nerve ganglia. It continues to multiply and spread along the affected nerve reaching the skin and causing shingles rash and neuropathic pain.
What factors can trigger shingles?
-Emotional stress
-Immunosuppression (chemotherapy,high steroid therapy)
-Recent illness or surgery
-Skin injury (sunburn, trauma,etc)
However, in majority of people, there is no identifiable risk
What are the 3 clinical phases of shingles presentation?
-Prodromal phase (burning pain over affected dermatome for 2-3 days,malaise,enlarged lymph nodes)
-Infectious rash (initially erythematous, macular rash over the affected dermatome
quickly becomes vesicular.Is unilateral,rarely crosses midline)
-Resolution rash (The vesicular rash crusts over within 10-12 days of rash onset
The crusted lesions can take up to one month to completely disappear)
What is the management plan for shingles?
Mainly supportive management (avoid pregnant women,immunocompromised pts and covering lesions)
Analgesia (NSAIDs and paracetamol are first line but if neuropathic agents like amitrptyline can be used if not responding to drugs above)
Oral corticosteroids —> considered for immunocompromised pts within first 2 weeks if pain is severe and not responding to other treatments
Antivirals (Oral antivirals given within 72 HOURS if pts fall under this criteria:
1. Immunocompromised pts
2. Non-truncal involvement (as shingles usually cause rashes in trunk area. So use antiviral if they affect areas like the neck, limbs,perineum)
3. Moderate to severe rash
4. Moderate to severe pain
5. If pt is OVER the age of 50 yrs to reduce the incidence of post-herpetic neuralgia, which is common in this age group.)
What are some complications of shingles?
Post herpetic neuralgia (common in pts over the age of 50 yrs)
Herpes zoster oticus (Ramsay Hunt syndrome—> shingles outbreak near facial nerve near one of the ears so develop facial paralysis and ear lesions and hearing loss in affected ear)
Herpes zoster opthalmicus (shingles affecting occular division of the trigeminal nerve)
