🎧 MSRA Deep Dive: Shingles – High-Yield Revision Essentials
Get exam-ready with this concise breakdown of shingles (herpes zoster) – covering pathophysiology, risk factors, red flags, and NICE-aligned management. Perfect for MSRA prep! 🧠

🧠 Core Learning Points

📌 Definition
• Reactivation of latent Varicella-Zoster Virus (VZV)
• Causes painful, unilateral, vesicular rash in a dermatomal pattern
• Commonly affects thoracic dermatomes or cranial nerves

📌 Pathophysiology
• After chickenpox, VZV lies dormant in sensory dorsal root ganglia
• Reactivation → virus travels along nerve → dermatomal rash
• Triggered by immunosuppression, age, stress
🧠 Mnemonic: “VIRUS” – VZV Reactivation In Unilateral Segment

📌 Risk Factors
• Age >50
• HIV (15x increased risk)
• Chemotherapy, immunosuppressants, long-term steroids
• Bone marrow transplant, lymphoma
• Stress
• Hx of chickenpox is a prerequisite

📌 Clinical Features
Prodrome (2–3 days):
– Burning/tingling pain
– Fever, malaise, local lymphadenopathy

Eruptive Phase:
– Red → vesicular → crusting rash in one dermatome
– Does not cross midline
– Lasts 2–4 weeks
– Ophthalmic zoster: affects eye – URGENT referral

Postherpetic Neuralgia (PHN):
– Pain lasting ≥30 days after rash resolves
– Risk ↑ with age

📌 Differentials
• HSV
• Contact dermatitis
• Eczema herpeticum
• Impetigo
• Insect bites
• Migraine/angina (if prodrome only)

📌 Infectivity & Transmission
• Shingles = not contagious as shingles
• VZV from blister fluid can cause chickenpox in non-immune individuals
• Avoid contact with:
– Pregnant women without immunity 🤰
– Neonates 👶
– Immunocompromised 💉

📌 Investigations
• Clinical diagnosis is usually sufficient
• Consider PCR of vesicle fluid if:
– Atypical features
– Immunocompromised patient
– Disseminated or severe disease
• IgM, Tzanck smear (older method) rarely used
• Eye involvement → urgent ophthalmology assessment

📌 Management (NICE/CKS aligned)

💊 Antivirals (start within 72h ideally):
• Aciclovir, valaciclovir, famciclovir
• Give to:
– Adults >50
– Immunocompromised
– Severe pain or non-truncal involvement
🕒 Start even after 72h if high-risk or ongoing vesicle formation

💥 Pain Relief
• 1st line: Paracetamol ± NSAIDs
• 2nd line: Amitriptyline, gabapentin, pregabalin, duloxetine
• Topical lidocaine patches may help
• Corticosteroids: reserved for severe acute pain (selected adults)

👁️ Referral Needed If:
• Ophthalmic zoster
• Immunocompromised
• Disseminated rash or complications
• Neurological signs (e.g., meningitis)
• Pregnant women
• PHN – consider pain clinic

📌 Complications
• PHN – burning nerve pain (up to 30% in older adults)
• Ophthalmic zoster – uveitis, keratitis, vision loss
• Ramsey Hunt syndrome – facial paralysis, ear pain, hearing loss
• Skin scarring, pigmentation
• Secondary infection
• Neurological – meningitis, encephalitis, myelitis
• Disseminated zoster – esp. in immunocompromised

📌 Prognosis
• Most recover in 2–4 weeks
• PHN may persist for months/years
• Early antiviral treatment = ↓ PHN risk
• Mortality rare – mainly in immunocompromised

📌 Vaccination
• Shingles vaccine (Shingrix) offered to older adults to reduce risk
• Chickenpox vaccine not routine in UK (due to theoretical effects on herd immunity)

📎 More Free MSRA Shingles Resources

📝 Revision Notes
https://www.passthemsra.com/topic/shingles-revision-notes/

🧠 Flashcards
https://www.passthemsra.com/topic/shingles-flashcards/

💬 Accordion Q&A Notes
https://www.passthemsra.com/topic/shingles-accordion-qa-notes/

🚀 Rapid Quiz
https://www.passthemsra.com/topic/shingles-rapid-quiz/

🧪 Topic Quiz
https://www.passthemsra.com/quizzes/shingles/

🎓 Dermatology Course
https://www.passthemsra.com/courses/dermatology-for-the-msra/

🔖 Hashtags
#MSRA #Shingles #DermatologyMSRA #MSRARevision #MSRAFlashcards #MSRAQuiz #VZV #HerpesZoster #PostherpeticNeuralgia