what does herpes look like in mouth

Oral Manifestations of Herpes Simplex Virus Type 1 (HSV-1)

Herpes simplex virus type 1 (HSV-1) commonly causes infections in the oral region. These infections manifest with characteristic signs and symptoms.

Primary Herpetic Gingivostomatitis

This is usually the initial presentation of HSV-1, typically occurring in children but can also affect adults without prior exposure. It involves widespread inflammation of the oral mucosa.

  • Vesicle Formation: Small, fluid-filled blisters appear on the gums, tongue, inner cheeks, and palate. These vesicles are fragile and rupture quickly.
  • Ulceration: Ruptured vesicles form painful, shallow ulcers with a red halo.
  • Gingivitis: The gums become inflamed, swollen, and bleed easily.
  • Systemic Symptoms: Fever, malaise, irritability, and swollen cervical lymph nodes are common.

Recurrent Herpes Labialis (Cold Sores)

After the primary infection, the virus becomes latent in the trigeminal ganglion. Reactivation can lead to recurrent episodes, typically affecting the lips (herpes labialis).

  • Prodromal Symptoms: A tingling, itching, or burning sensation often precedes the appearance of lesions.
  • Vesicle Formation: Small, painful blisters develop, usually on the vermilion border of the lip.
  • Crusting: Vesicles rupture, forming a crust that eventually falls off.
  • Location: Recurrent lesions typically occur in the same location each time.

Intraoral Recurrences

Less commonly, HSV-1 reactivation can cause intraoral lesions, usually on keratinized surfaces like the hard palate and gingiva, in immunocompromised individuals or those with specific underlying conditions. These differ from aphthous ulcers (canker sores).

  • Location: Typically found on the hard palate or attached gingiva.
  • Appearance: Clusters of small ulcers.
  • Predisposing Factors: Immunocompromise, trauma.

Diagnosis and Differential Diagnosis

Diagnosis is often based on clinical presentation. However, viral cultures, PCR testing, or Tzanck smear can be used for confirmation. Differential diagnosis includes aphthous stomatitis (canker sores), herpangina, hand-foot-and-mouth disease, and other vesiculobullous diseases.