What is the diagnosis and management for a 42-year-old male (m) smoker with a 20 pack-year history, presenting with a 3-day history of painful, itchy blisters in the right ear with clear liquid discharge, who has been scratching the area, with no reported facial paralysis, fever, or systemic symptoms?

Diagnosis: Herpes Zoster Oticus (Ramsay Hunt Syndrome)

This patient has herpes zoster oticus (Ramsay Hunt syndrome), and requires immediate initiation of systemic antiviral therapy plus corticosteroids to prevent permanent facial nerve damage and other complications. 1

Clinical Reasoning

The presentation of painful, itchy vesicles with clear fluid in the right ear canal in a 42-year-old male is highly characteristic of herpes zoster oticus. 1 Key diagnostic features present in this case include:

• Unilateral vesicular eruption in the ear canal - pathognomonic for herpes zoster oticus 1
• Clear vesicular fluid - typical of viral rather than bacterial infection 1
• Painful and pruritic - consistent with acute viral neuritis 2, 3
• Localized to single dermatome (ear canal) without spread - classic presentation 3

Critical assessment point: The patient currently reports NO facial paralysis, but this does NOT rule out Ramsay Hunt syndrome. 1 Facial nerve involvement can develop hours to days after vesicle appearance, making early antiviral treatment essential to prevent this devastating complication. 1

Differential Diagnosis Considerations

The American Academy of Otolaryngology-Head and Neck Surgery distinguishes herpes zoster oticus from acute otitis externa by the presence of vesicles on the external ear canal and posterior auricle, which are pathognomonic for viral infection rather than bacterial infection. 1

Why this is NOT acute otitis externa:

• Vesicular lesions (not seen in bacterial AOE) 1
• Clear fluid discharge (bacterial AOE has purulent discharge) 1
• No fever or systemic symptoms (bacterial AOE often presents with these) 1

Why this is NOT contact dermatitis:

• Vesicles with clear fluid (contact dermatitis presents with erythema, scaling, and eczematous eruption without true vesicles) 1
• Acute onset over 3 days (contact dermatitis is typically more gradual) 1

Immediate Management Algorithm

Step 1: Initiate Antiviral Therapy IMMEDIATELY

The American Academy of Otolaryngology-Head and Neck Surgery recommends prompt systemic antiviral therapy for herpes zoster oticus. 1 Treatment must begin within 72 hours of symptom onset for maximum efficacy. 3

First-line antiviral options (in order of preference):

• Valacyclovir 1000 mg three times daily for 7 days 3
• Famciclovir 500 mg three times daily for 7 days 3
• Acyclovir 800 mg five times daily for 7 days (if others unavailable) 3

Valacyclovir and famciclovir are preferred over acyclovir due to superior bioavailability and more convenient dosing schedules, which improves adherence. 3

Step 2: Add Systemic Corticosteroids

The American Academy of Otolaryngology-Head and Neck Surgery recommends systemic steroids in addition to antivirals for herpes zoster oticus. 1 This combination reduces the risk of facial paralysis and postherpetic neuralgia. 2

Corticosteroid regimen:

• Prednisone 60 mg daily for 7 days, then taper over 7-14 days 2
• Must be started concurrently with antivirals, not as monotherapy 2

Step 3: Aggressive Pain Management

Pain in herpes zoster can be severe and debilitating. 2, 4 The American Academy of Otolaryngology-Head and Neck Surgery emphasizes that adequate analgesia during the acute phase may reduce the risk of postherpetic neuralgia. 1

Pain management strategy:

• Mild-to-moderate pain: NSAIDs (ibuprofen 600 mg three times daily) or acetaminophen 5
• Moderate-to-severe pain: Strong opioids (oxycodone 5-10 mg every 4-6 hours as needed) 2
• Consider adding: Gabapentin 300 mg three times daily (titrate up as needed) to address neuropathic component and potentially prevent postherpetic neuralgia 2, 4

Step 4: Monitor for Complications

Daily assessment for the first 72 hours is critical to detect:

• Facial nerve paralysis or paresis - requires urgent escalation of treatment 1
• Loss of taste on anterior two-thirds of tongue - indicates geniculate ganglion involvement 1
• Decreased lacrimation - suggests facial nerve involvement 1
• Spread beyond ear canal - may indicate disseminated disease requiring hospitalization 3

Special Considerations for This Patient

Smoking History (20 pack-years)

This patient's significant smoking history may impair immune function and increase risk of complications. 2 While not an absolute indication for hospitalization, closer monitoring is warranted. 2

No Immunocompromise Reported

The absence of diabetes, HIV, malignancy, or immunosuppressant use is reassuring, as immunocompromised patients have higher risk of:

• Disseminated cutaneous disease 3
• Visceral involvement (pneumonia, hepatitis, encephalitis) 3
• Chronic or recurrent herpes zoster 3

However, do NOT delay treatment while awaiting immune status confirmation. 3

Critical Pitfalls to Avoid

1. Delaying antiviral therapy while awaiting laboratory confirmation - Diagnosis is clinical; treatment must begin immediately based on characteristic vesicular rash. 1, 3

2. Using topical therapy alone - Herpes zoster oticus requires systemic antivirals; topical agents are insufficient. 1

3. Prescribing corticosteroids without antivirals - Steroids alone show no protective effect and may worsen viral replication. 2

4. Assuming absence of facial paralysis means mild disease - Facial nerve involvement can develop after initial presentation; early treatment prevents this complication. 1

5. Inadequate pain control - Severe acute pain is a predictor of postherpetic neuralgia; aggressive early analgesia may reduce this risk. 2

6. Confusing with bacterial otitis externa and prescribing only topical antibiotics - This delays appropriate antiviral therapy and increases risk of permanent complications. 1

Expected Clinical Course

• Pain improvement: Should begin within 48-72 hours of starting antivirals 3
• Vesicle crusting: Typically occurs within 7-10 days 3
• Complete resolution: Usually 4-5 weeks 4
• Postherpetic neuralgia risk: Approximately 10-15% in this age group if treated promptly; higher if treatment delayed 2, 3

Follow-Up Plan

Reassess within 48-72 hours to evaluate:

• Response to antiviral therapy 3
• Development of facial nerve symptoms 1
• Adequacy of pain control 2
• Spread of vesicular lesions 3

If no improvement or worsening at 48-72 hours: Consider hospitalization for IV acyclovir, especially if facial paralysis develops or systemic symptoms emerge. 3