Msk Dermatology · Year 2 · from Msk Dermatology

Case 2: Herpes Zoster (Shingles)

Patient Presentation

Demographics: 72-year-old female

Chief Complaint: Painful rash on left chest and back for 3 days

History of Present Illness: The patient developed burning pain on her left chest 5 days ago, which she initially attributed to muscle strain. Two days later, she noticed grouped blisters appearing in the same area. The rash has spread along her left side in a band-like pattern but does not cross the midline. The pain is severe, described as burning and stabbing.

Past Medical History:

  • Hypertension
  • Osteoarthritis
  • Chickenpox as a child
  • Never received zoster vaccine

Physical Examination:

  • Temperature: 37.8C
  • Left T4-T5 dermatome:
  • Grouped vesicles on an erythematous base
  • Some vesicles with central umbilication
  • Erosions where vesicles have ruptured
  • Dermatomal distribution (does not cross midline)
  • Severe allodynia (pain to light touch)

Workup and Results

Clinical Diagnosis:

  • Classic presentation - laboratory confirmation not required

If needed:

  • Tzanck smear: Multinucleated giant cells (positive)
  • VZV PCR from vesicle fluid: Positive

Clinical Image

Clinical photograph demonstrating herpes zoster with characteristic grouped vesicles on an erythematous base in a dermatomal distribution (T4-T5), stopping at the midline.

Diagnosis

Herpes Zoster (Shingles) - Thoracic Dermatome

Features:

  • Reactivation of varicella-zoster virus from dorsal root ganglion
  • Dermatomal, unilateral distribution
  • Grouped vesicles on erythematous base

Discussion

This case illustrates herpes zoster:

  • Dermatomal Distribution: The lecture describes herpes zoster as having a dermatomal, unilateral distribution. The virus reactivates from the dorsal root ganglion where it has remained latent since primary varicella infection.
  • 72-Hour Window: The lecture emphasizes that treatment with antivirals is most effective when started within 72 hours of rash onset. This patient presented at day 3, still within the treatment window.
  • Tzanck Smear: The lecture identifies the Tzanck smear as useful for rapid diagnosis of herpesvirus infections. It shows multinucleated giant cells but cannot distinguish HSV from VZV.
  • Grouped Vesicles: The lecture describes the characteristic appearance of herpesviruses as grouped vesicles on an erythematous base.

Treatment Plan

  1. Antiviral Therapy (within 72 hours):
  • Valacyclovir 1000 mg three times daily for 7 days
  • OR Famciclovir 500 mg three times daily for 7 days
  • Reduces severity, duration, and risk of postherpetic neuralgia
  1. Pain Management:
  • Acetaminophen and NSAIDs
  • Gabapentin or pregabalin for neuropathic pain
  • Opioids if needed for severe pain
  1. Wound Care:
  • Keep lesions clean and dry
  • Calamine lotion for symptomatic relief
  • Avoid contact with immunocompromised individuals
  1. Monitoring:
  • Watch for bacterial superinfection
  • Monitor for postherpetic neuralgia
  • Eye exam if facial involvement (herpes zoster ophthalmicus)
  1. Prevention:
  • Recommend Shingrix vaccine after recovery (prevents recurrence)

Teaching Points

  1. Herpes zoster is dermatomal and unilateral (does not cross midline)
  2. Antiviral treatment most effective if started within 72 hours
  3. Tzanck smear shows multinucleated giant cells
  4. Grouped vesicles on erythematous base are characteristic of herpesviruses
  5. Postherpetic neuralgia is a major complication, especially in elderly

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