Varicella Zoster

Question 1

Define Varicella Zoster?

Answer 1

Primary infection is called varicella (chickenpox)

Reactivation of the dormant virus (found in dorsal root ganglia) causes zoster (shingles)

Question 2

What is Varicella Zoster also known as?

Answer 2

Herpes Zoster

Question 3

What is the aetiology of Varicella Zoster?

Answer 3

VZV is a herpes ds-DNA virus
Highly contagious
Transmission by aerosol inhalation or direct contact with vesicular secretions

Question 4

What is the epidemiology of Varicella Zoster?

Answer 4

Chicken pox peak incidence: 4-10 yrs
Shingles peak incidence: > 50 yrs
90% of adults are VZV IgG positive

Question 5

What are the presenting symptoms of Chickenpox?

Answer 5

Prodromal Malaise
Mild Pyrexia
Sudden apperance of intensely itchy spreading rash mainly affecting face and trunk
Vesicles weep and crust over
New vesicles appear
Contagious from 48 hrs before the rash until after the vesicles have all crusted over (7-10 days)

Question 6

What are the presenting symptoms of Shingles?

Answer 6

May occur after a period of stress
Tingling/hyperaesthesia in a dermatomal distribution
Painful skin lesions
Recovery: 10-14 days

Question 7

Why is it a Dermatomal Distribution for Shingles tingling?

Answer 7

Dermatomal because the rash remains dormant in the dorsal root ganglia and reactivation makes the virus travel down the sensory axon to produce a dermatomal shingles rash

Question 8

What are the signs of Chickenpox on physical examination?

Answer 8

Maculopapular rash
Areas of weeping and crusting
Skin excorciation (from scratching)
Mild pyrexia

Question 9

What are the signs of Shingles on physical examination?

Answer 9

Vesicular maculopapular rash
Dermatomal Distribution
Skin Excoriation

Question 10

What investigations would you do for Varicella Zoster?

Answer 10

Usually CLINICAL diagnoses
Vesicle fluid may be sent for electron microscopy viral PCR (RARELY necessary)
Chicken pox in an adult with previous history of varicella infection may require HIV testing

Question 11

What is the management plan for Chickenpox?

Answer 11

Children - treat symptoms

Adults - consider aciclovir

Question 12

What is the management plan for Shingles?

Answer 12

Aciclovir
Valaciclovir
Famciclovir

Question 13

What is the prevention for Varicella Zoster?

Answer 13

Varicella Zoster Ig (VZIG) - may be considered in immunosuppressed or pregnant

Question 14

What are the possible complications for Chickenpox?

Answer 14

Secondary Infection
Scarring
Pneumonia
Encephalitis 
Congenital Varicella Syndrome

Question 15

What is the possible complications of Shingles?

Answer 15

Postherpetic neuralgia 
Zoster ophthalmicus 
Ramsey-Hunt Syndrome
Sacral Zoster 
Motor Zoster

Question 16

What is Zoster Ophthalmicus?

Answer 16

Rash in the ophthalmic division of the trigeminal nerve

Question 17

What is Ramsay-Hunt Syndrome?

Answer 17

Reactivation of VZV in the geniculate ganglion causing zoster of the eye and facial nerve palsy
Vesicles may be seen behind the pinna of the ear or in the ear canal

Question 18

What is the prognosis for patients with Varicella Zoster?

Answer 18

Depends on complications

Worse in pregnancy, elderly and immunoccompromised