Shingles, Awakening of a Dormant Disease

1
Shingles, Awakening of a Dormant Disease

• Kievers L. Cunningham, MD

2
Overview

• Herpes zoster (commonly referred to as
  "shingles") and post herpetic neuralgia result
  from reactivation of the varicella-zoster virus
  acquired during the primary varicella infection,
  or chickenpox.
• Varicella is generally a disease of childhood.
• Herpes zoster and post herpetic neuralgia become
  more common with increasing age.

3
Overview

• Factors that decrease immune function may also
  increase the risk of developing herpes zoster.
• E.g.- human immunodeficiency virus infection,
  chemotherapy, malignancies, chronic
  corticosteroid use, and aging.

4
Epidemiology

• Sporadic disease- lifetime incidence of 10 to 20
  percent.
• The incidence of herpes zoster increases sharply
  with advancing age, roughly doubling in each
  decade past the age of 50 years.
• Herpes zoster is uncommon in persons less than 15
  years old.

5
Epidemiology

• The incidence of herpes zoster is up to 15 times
  higher in HIV-infected patients than in
  uninfected persons, and as many as 25 percent of
  patients with Hodgkin's lymphoma develop herpes
  zoster.
• Herpes zoster in HIV-infected patients does not
  appear to increase the risk of acquired
  immunodeficiency syndrome (AIDS

6
Epidemiology

• No clinically significant differences between
  race.
• Although herpes zoster is not as contagious as
  the primary varicella infection, persons with
  reactivated infection can transmit
  varicella-zoster virus to nonimmune contacts.
• The most established risk factor is age this
  complication occurs nearly 15 times more often in
  patients more than 50 years of age.

7
Pathophysiology

• Varicella-zoster virus is a highly contagious DNA
  virus.
• Varicella represents the primary infection in the
  nonimmune or incompletely immune person.
• During the primary infection, the virus gains
  entry into the sensory dorsal root ganglia.
• How the virus enters the sensory dorsal root
  ganglia and whether it resides in neurons or
  supporting cells are not completely understood.

8
Pathophysiology

• The virus remains latent for decades because of
  varicella-zoster virusspecific cell-mediated
  immunity acquired during the primary infection.
• Reactivation of the virus occurs following a
  decrease in virus-specific cell-mediated
  immunity.
• The reactivated virus travels down the sensory
  nerve and is the cause for the dermatomal
  distribution of pain and skin lesions.

9
Pathophysiology

• The pathophysiology of postherpetic neuralgia
  remains unclear.
• Pathologic studies - damage to the sensory
  nerves, the sensory dorsal root ganglia and the
  dorsal horns of the spinal cord.

10
(No Transcript)
11
Clinical Presentation- Symptoms

• Malaise
• Headache
• Acute, knife-like pain (with tingling and
  itching) that occurs 3-5 days before the rash in
  the dermatome where the rash will appear
• Weakness
• Fever
• Acute loss of hearing, vertigo, and paralysis of
  the affected side of the face may occur in herpes
  zoster of the facial nerve (Ramsay Hunt syndrome)

12
Clinical Presentation- Signs

• Closely grouped red papules, which rapidly become
  vesicular, appear in a continuous, uninterrupted
  band, generally in a single dermatome
• A few patients have some vesicles outside the
  affected dermatome
• Rash is almost always unilateral
• Appearance of the rash may be the first sign in
  children

13
Clinical Presentation- Signs

• Lymph nodes draining the affected area may be
  enlarged and tender
• Vesicles become papular and/or hemorrhagic in 1-4
  days
• Vesicles have a red base and are cloudy in
  appearance
• Vesicles are of different sizes
• Vesicles become umbilicated and then form crusts
  that fall off in about 3 weeks, generally leaving
  some scarring

14
(No Transcript)
15
(No Transcript)
16
(No Transcript)
17
Differential Diagnosis- Rash

• Herpes simplex virus infection
• Disseminated coxsackievirus infection
• Contact dermatitis
• Autoimmune bullous skin diseases
• Blistering bacterial infection

18
Differential Diagnosis- Pain

• Cholecystitis
• Pleuritic chest pain
• Myocardial infarction
• Pericarditis
• Renal colic
• Prolapsed disc

19
Treatment- Acute Infection

• Antiviral Therapy- Acyclovir (Zovirax),
  Valcyclovir(Valtrex), Famciclovir(Famvir) and
  Foscarnet.
• Acyclovir- moderately active against zoster/most
  clinical data cost (inexpensive) multiple time
  daily(5x)
• Treatment should be initiated 48-72 hour after
  onset of symptoms- ? post-herpetic neuralgia and
  healing time.

20
Treatment- Acute Infection

• Newer Antivirals-Valcyclovir and Famciclovir
• Valcyclovir- 1st line- rapid resolution of
  neuritis, pain and post-herpetic neuralgia (1
  gram TID PO x 7 days85)
• Famvir- more expensive than Valtrex(140) better
  bioavailability

21
Treatment- Acute Infection

• Prednisone (steroids)-may improve healing and
  healing time in severe cases when added to
  antiviral.
• Should not be given alone or extended beyond
  antiviral regimen,
• Do not give to HIV/AIDS patients.
• Should be given in reducing-dose or taper
  regimen.
• Treatment of choice for Ramsay Hunt Syndrome
  (facial nerve).

22
Treatment- Acute Infection

• Pain relief can be obtained by any of the
  following
• Acetaminophen
• Opioid analgesics
• NSAIDs arent recommended.
• Capsaicin (once lesions have crusted over)
• Calamine lotion
• Topical lidocaine/xylocaine
• Nerve blocks

23
Treatment- Post-Herpetic Neuralgia

• Anticonvulsants- gabapentin, phenytoin,
  carbamazapine
• Tricyclic Antidepressants amitriptyline,
  nortriptyline, imipramine etc.
• Topical- Capsaicin, lidocaine patch

24
Immunization

• Zostavax
• FDA approved in 2006
• Only licensed for prevention of zoster in patient
  60 years.
• Live attenuated virus
• Side effects- headache and injection site
  reaction
• Contraindicated- immunosuppression, pregnancy and
  hypersensitivity (anaphylactic reaction to
  gelatin or neomycin).

25
Immunization

• Shingles Prevention Study
• Followed for median of 3.1 years
• RRR 51
• ARR5.7
• NNT17
• ? Chicken Pox Vaccine

26
References

• 1. Donahue JG, Choo PW, Manson JE, Platt R. The
  incidence of herpes zoster. Arch Intern Med
  19951551605-9.
• 2. Dubinsky RM, Kabbani H, El-Chami Z, et al.
  Practice Parameter treatment of post-herpetic
  neuralgia an evidence-based report of the Quality
  Standards Subcommittee of the American Academy of
  Neurology. Neurology 200463959-65
• 3. Mounsey AL, Matthew LG, Slawson DC. Herpes
  Zoster and Post-Herpetic Neuralgia Prevention
  and Managment. Am Fam Physician 2005721075-80
• 4. Dworkin RH, Johnson RW, Breuer J, et al.
  Recommendations for the management of herpes
  zoster. Clin Infect Dis 200744 Suppl 1S1-26.

27
Q A