Oral Herpes

Aka: Oral Herpes, Herpes Simplex Virus, Oral HSV, Orolabial Herpes, HSV I, Primary Herpetic Gingivostomatitis, Herpes Gingivostomatitis, Fever Blister, Cold Sore, Herpes Labialis, Herpes Simplex Stomatitis, Acute Herpetic Mucositis

1. See Also
   1. Genital Herpes
   2. Neonatal Herpes Simplex Virus
2. Epidemiology
   1. Prevalence:
      1. Antibody positive: 37% in U.S. college freshman and 46% in college seniors
      2. Cold Sore history: 25-28% of U.S. college students
   2. Age of transmission
      1. Childhood (most common)
      2. Young adults
3. Pathophysiology
   1. Etiology: HSV I (less commonly HSV II)
   2. Transmission via mucous membranes or open skin
      1. Kissing
      2. Fomites (e.g shared towels, utensils)
   3. Incubation: 2-20 days after contact
   4. Shedding: 48-60 hour duration (not longer than 96 hours)
   5. HSV lies dormant after initial infection
      1. Distributed in the trigeminal Ganglion
      2. Reactivation with triggers as described below
   6. Triggers for recurrence
      1. Fever
      2. Emotional stress
      3. Sun Exposure
      4. Trauma
      5. Immunocompromised state
      6. Menses
      7. Fatigue
4. Symptoms
   1. Primary (Initial) HSV I: Usually asymptomatic (but first episode is most severe)
      1. Fever, chills
      2. Cervical Lymphadenopathy
      3. Ulcers deep in mouth on Gingival surface
      4. Avoidance of drinking, eating de to pain
   2. Secondary (Later) HSV I (Recurrent labial lesions)
      1. Provocative factors for recurrence: See above
      2. Frequency: 1-6 episodes per year
      3. Lesions form along vermillion border
         1. Fever Blisters form on outer vermillion border
         2. Cold Sores form on inner lip
      4. Course
         1. Prodrome: Itch, burn, or tingling for 12-36 hours (60% of cases)
         2. Vesicle forms
         3. Vesicle ruptures, ulcerates and crusts in 48 hours
         4. Lesion heals in 10-14 days
5. Signs
   1. Lesion characterictics
      1. Grouped Vesicles on erythematous base
      2. Forms on epithelial surface at vermillion border edge
      3. Vesicular lesions rupture to form painful Ulceration
      4. Distribution: Lips, Gingiva, Palate, Tongue
   2. Associated findings
      1. Cervical Lymphadenopathy
6. Complications
   1. Herpes Keratitis (Corneal infection)
   2. Herpetic Whitlow (painful vesicular lesions on fingers)
   3. Herpetic sycosis (beard area vesicular eruption)
   4. Herpes gladiatorum (vesicular lesions typically on torso with history of wrestling exposure)
   5. Erythema Multiforme (HSV is the most common cause)
   6. HSV Encephalitis
7. Differential Diagnosis
   1. Oral Lesions
      1. Aphthous Ulcers
      2. Behcet Syndrome
      3. Herpangina
   2. Skin lesions
      1. Herpes Zoster (Shingles)
      2. Herpes Gestationis
      3. Pemphigus Vulgaris
      4. Varicella
8. Differential Diagnosis: Distinguishing features
   1. Differs from Aphthous Ulcers in that:
      1. Found on keratinized (bound-down) intraoral mucosa
      2. Vesicles rupture into coalescing ulcers
   2. HSV lesions are anterior compared with:
      1. Herpangina
      2. Hand Foot and Mouth Disease
9. Labs:
   1. Viral culture for HSV
      1. Vesicles are most concentrated with infection within first 48 hours
      2. Unroof Vesicles with scalpel or needle tip and apply viral culture swab
      3. Expect viral growth within 5 days
      4. Test Sensitivity: 50%
   2. HSV PCR
      1. Test Sensitivity: High
   3. HSV Direct Fluorescent Antibody
      1. Test Sensitivity: 80%
   4. HSV IgG
      1. Antibodies form with weeks of primary infection
      2. Does not differentiate acute infection from prior
   5. Rapid Giemsa (Dif-Quik) stain
      1. Multinucleated giant cells
      2. Test Sensitivity: 40-77%
10. Management: General Measures
    1. Magic Mouthwash
       1. Indicated for analgesia
11. Management: Primary Outbreak (Initial)
    1. Acyclovir (not FDA approved)
       1. Dose: 15 mg/kg (max: 200 mg) orally 5 times per day for 7 days
    2. Efficacy
       1. Lesions resolved in 4 versus 10 days, and viral shedding decreased to 1 versus 5 days
       2. Amir (1997) BMJ 314:1800-3
12. Management: Recurrent Outbreaks
    1. Systemic antiviral agents
       1. Acyclovir (Zovirax)
          1. Child: 15 mg/kg (max: 200 mg) orally 5 times per day for 5 days
          2. Adult:
             1. 200 mg orally 5 times daily for 5 days or
             2. 400 mg orally 3 times daily for 5 days
       2. Famciclovir (Famvir)
          1. Adult: 1500 mg orally for one dose
          2. Efficacy
             1. Shortens healing time by 2 days in UV-induced cases
             2. Spruance (1999) J Infect Dis 179:303-10
       3. Valacyclovir (Valtrex)
          1. Adult: 2 grams orally twice daily for one day
    2. Topical antiviral agents (reduce healing time by 0.7 days)
       1. Acyclovir cream apply 5 times per day for 4 days
       2. Docosanol (Abreva) cream apply 5 times per day until healed
       3. Penciclovir (Denavir) 1% cream apply every 2 hours while awake for 4 days
13. Management: Prevent recurrence (daily suppression)
    1. Acyclovir (Zovirax) 400 mg orally twice daily
    2. Valacyclovir 500 mg orally once daily
14. References
    1. Colgan (2003) Am Fam Physician 67(4):757-62
    2. Usatine (2010) Am Fam Physician 82(9):1075-82