Epidemiology
Etiology
Pathophysiology
Clinical features
- Main symptoms: dermatomal distribution, typically affecting 1–3 dermatomes on one side of the body (most commonly affects the cervical, trigeminal, thoracic, and lumbar dermatomes)
- Pain
- The most frequent symptom and may precede the rash
- Usually described as “burning”, “throbbing”, or “stabbing”
- Allodynia may occur.
- Erythematous maculopapular rash that quickly evolves into vesicular lesions
- Vesicles are initially clear.
- Pustulation and rupture typically occur after 3 or 4 days.
- Crusting and involution typically occurs between day 7 and 10.
- Lesions may become necrotic, generalized, or may not be present at all.
- Pain
- Additional symptoms
- Fever, headache, and fatigue
Subtypes and variants
Herpes zoster ophthalmicus (HZO)
- Definition: reactivation of VZV in the ophthalmic division of the trigeminal nerve
- Clinical features
- Fever and skin symptoms as in shingles
- Herpes zoster conjunctivitis
- Herpes zoster keratitis
- Involvement of the ophthalmic nerve: reduced corneal sensitivity with severe pain in the innervated regions (forehead, bridge and tip of the nose)
- Involvement of the nasociliary nerve:
- Possible severe intraocular infection (uveitis, iritis, conjunctivitis, keratitis, and optic neuritis)
- Positive Hutchinson sign of the nose: a vesicular rash on the nasal alae
Diagnostics
Positive Hutchinson sign of the nose: a vesicular rash on the nasal alae
Treatment
Complications
Postherpetic neuralgia
- Definition: chronic neuropathic pain persisting for at least three months in the area previously affected by the rash
- Epidemiology
- Most common complication (occurs in 10–20% of overall herpes zoster cases)
- Strong association with age
- Risk factors
- Age > 50 years
- Severe infection (severe pain or rash)
- Clinical features
- Pain (including allodynia, paresthesias, dysesthesias) in the same dermatome as the rash
- Duration of symptoms > 3 months but can persist for years
- Treatment
- One of the following tricyclic antidepressants:
- Reduces serotonin and norepinephrine at the same time
- Amitriptyline
- Nortriptyline
- Relative contraindications: patients with heart disease, epilepsy, or glaucoma
- Should be used with caution in elderly patients
- One of the following anticonvulsants:
- Pregabalin
- Gabapentin
- Topical treatments
- Capsaicin patch or cream
- One of the following tricyclic antidepressants: