SPOTTERS MEDICINE
HERPES ZOSTER
🔹 Definition:
Herpes
Zoster is a viral reactivation of latent Varicella Zoster Virus (VZV)
in dorsal root or cranial nerve ganglia, leading to painful vesicular rash
along a dermatomal distribution.
🔹 Causative Organism:
- Varicella Zoster Virus (VZV)
- After primary infection
(chickenpox), VZV lies dormant in sensory ganglia
🔹 Risk Factors:
- Older age (>50 years)
- Immunosuppression (HIV, cancer, chemotherapy)
- Physical or emotional stress
- Organ transplant recipients
🔹 Pathogenesis:
- Reactivation of dormant VZV →
viral replication in neurons
- Spread along the nerve to skin →
inflammation and vesicular eruptions in a unilateral dermatomal pattern
🔹 Clinical Features:
- Prodrome: burning pain, tingling, fever,
malaise (2–3 days before rash)
- Rash: grouped vesicles on
erythematous base, unilateral, dermatomal
- Common sites: thoracic (T3–L2), trigeminal
(especially ophthalmic division – Herpes Zoster Ophthalmicus)
- Postherpetic neuralgia (PHN) – persistent pain after rash
heals
🔹 Complications:
- Postherpetic neuralgia (most common)
- Herpes zoster ophthalmicus – can cause blindness
- Secondary bacterial infection
- Disseminated zoster in
immunocompromised
🔹 Diagnosis:
- Clinical based on rash pattern
- Tzanck smear: multinucleated giant cells
- PCR or direct fluorescent
antibody (DFA)
tests – confirmatory
🔹 Treatment:
Antiviral
therapy (start within 72 hours):
- Acyclovir, Valacyclovir, or Famciclovir
Pain
control:
- NSAIDs, gabapentin, pregabalin
- Amitriptyline for neuralgia
Eye
involvement:
- Immediate referral to
ophthalmologist
- Topical and systemic antivirals
🔹 Prevention:
- Zoster vaccine (Recombinant zoster vaccine –
RZV/Shingrix):
- Recommended >50 years
- Varicella vaccine in children prevents primary
VZV infection
🔹 Prognosis:
- Self-limiting in most healthy
individuals
- Risk of PHN increases with age
and immunosuppression
DR.C.GANESAN M.D.
PROFESSOR OF MEDICINE
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