198.3 🩺 內科專科考前版

198.3.0.1 1⃣ Shingrix in Immunocompromise (Ch 198 update)

  • 2021 ACIP expansion: ≥ 19 yr immunocompromise
  • Includes HSCT, SOT, hematologic malignancy, HIV (any CD4)
  • 2 doses 1-2 mo apart (faster than general 50+)
  • Efficacy lower (~ 70%) but still beneficial
  • Pre-transplant vaccination encouraged

198.3.0.2 2⃣ PHN Prevention

  • Early antiviral (< 72 hr) reduces PHN risk slightly
  • Vaccination = best prevention
  • Steroid: doesn’t reduce PHN
  • Gabapentinoid early treatment + may reduce PHN slightly (mixed)
  • Acupuncture, capsaicin some evidence

198.3.0.3 3⃣ Herpes Zoster Ophthalmicus Management

  • Emergent ophthalmology consult
  • IV acyclovir 10 mg/kg q8h × 7-14d
  • Topical antiviral (trifluridine, ganciclovir gel)
  • Steroid eye drops only under ophthalmology
  • Pain management
  • Monitor for: keratitis, uveitis, retinitis (acute retinal necrosis), VI palsy
  • Long follow-up (sequelae possible)

198.3.0.4 4⃣ Ramsay Hunt Syndrome

  • Geniculate ganglion VZV reactivation
  • VII (facial) + VIII (auditory) involvement
  • Facial palsy + ear vesicles + vertigo + hearing loss + tinnitus
  • Higher residual paralysis vs Bell’s palsy
  • Treatment: acyclovir IV + steroid
  • ENT + neurology consult

198.3.0.5 5⃣ Acute Retinal Necrosis (ARN)

  • VZV (or HSV) retinitis
  • Rapidly progressive retinal necrosis + vasculitis
  • Visual loss, retinal detachment
  • IV acyclovir × 14d → PO valacyclovir × 4-6 wk
  • Intravitreal foscarnet adjunct
  • Vitrectomy for retinal detachment

198.3.0.6 6⃣ VZV Encephalitis / Vasculopathy

  • Large + small vessel vasculopathy
  • Ischemic + hemorrhagic stroke in zoster patients (especially elderly)
  • CSF VZV PCR positive
  • MRI brain: vasculitis, infarcts
  • Acyclovir IV × 14-21d
  • Antiplatelet / anticoagulation per stroke management

198.3.0.7 7⃣ 健保 / Taiwan

  • 公費 Varivax childhood routine
  • Shingrix 自費 (about NT$5,000-7,000 per dose, 2 doses)
  • 健保 acyclovir / valacyclovir for confirmed zoster
  • IV acyclovir admit indication
  • 盧醫垫 hint: 糖尿病 / 慢病 / 老 50+ 䞀定芁 push Shingrix 自費 vaccine — PHN 對 quality of life 倪砎壞

198.3.0.8 8⃣ Vaccine Hesitancy + Counseling

  • Common reasons: cost, “I’m healthy”, “I had chickenpox so I’m immune”
  • Counter:
    • Cost vs cost of zoster + PHN
    • Reactivation risk regardless of past varicella history (in fact requires past varicella)
    • PHN devastating impact
  • Shared decision-making

198.3.0.9 9⃣ Future

  • mRNA zoster vaccines in development
  • New antivirals (helicase-primase inhibitor, novel mechanism)
  • Anti-PHN strategies (botulinum toxin trials)