Oral-Facial Infections

Primary HSV-1 infection results in gingivostomatitis, pharyngitis, and up to 2 weeks of fever, malaise, myalgia, inability to eat, and cervical adenopathy, with lesions on the palate, gingiva, tongue, lip, face, posterior pharynx, and/or tonsillar pillars and occasional exudative pharyngitis.

• Reactivation of HSV from the trigeminal ganglia is associated with asymptomatic viral excretion in the saliva, intraoral mucosal ulcerations, or ulcers on the vermilion border of the lip or external facial skin.
  • Approximately 50-70% of pts undergoing trigeminal nerve-root decompression and 10-15% of pts undergoing dental extraction develop oral-labial herpes a median of 3 days after the procedure.
  • Reactivation of HSV-1 or VZV in the mandibular portion of the facial nerve causes flaccid paralysis (Bell's palsy).
• Immunosuppressed pts can have a severe infection that extends into the mucosa and skin, causing friability, necrosis, bleeding, pain, and inability to eat or drink.
• Pts with atopic dermatitis may also develop severe oral-facial HSV infection (eczema herpeticum), with extensive skin lesions and occasional visceral dissemination.
• HSV infection is the precipitating event in ∼75% of cases of erythema multiforme.

Genital Infections

First-episode primary genital herpes is characterized by fever, headache, malaise, and myalgias (see Chap. 86 Sexually Transmitted and Reproductive Tract Infections). Pain, itching, dysuria, vaginal and urethral discharge, and tender inguinal lymphadenopathy are the predominant local symptoms.

• Pts with prior HSV-1 infection have milder cases.
• Reactivation infections are often subclinical or can cause genital lesions or urethritis with dysuria.
• Even without a history of rectal intercourse, perianal lesions can occur as a result of latency established in the sacral dermatome from prior genital tract infection.

Whitlow

In HSV infection of the finger, pts experience an abrupt onset of edema, erythema, pain, and vesicular or pustular lesions of the fingertips that are often confused with the lesions of pyogenic bacterial infection. Fever, lymphadenitis, and epitrochlear and axillary lymphadenopathy are common.

Herpes Gladiatorum

HSV infection caused by trauma to the skin during wrestling can occur anywhere on the body but commonly affects the thorax, ears, face, and hands.

Eye Infections

HSV is the most frequent cause of corneal blindness in the United States.

• HSV keratitis presents as acute onset of pain, blurred vision, chemosis, conjunctivitis, and dendritic corneal lesions. Topical glucocorticoids may exacerbate disease. Recurrences are common.
• Other manifestations include chorioretinitis and acute necrotizing retinitis.

Central and Peripheral Nervous System Infections

In the United States, HSV causes 10-20% of all cases of sporadic viral encephalitis, and 95% of these cases are due to HSV-1 (either primary or reactivated infection). The estimated annual incidence is 2.3 cases per 1 million persons.

• Pts present with an acute onset of fever and focal neurologic symptoms and signs, especially in the temporal lobe. In severe cases, RBCs can be found in the CSF as a result of hemorrhagic necrosis.
• Given the potential severity of infection, antiviral treatment should be started empirically until the diagnosis is confirmed or an alternative diagnosis is made.
• HSV meningitis, which is usually seen in association with primary genital HSV infection, is an acute self-limited disease manifested by headache, fever, and mild photophobia and lasting 2-7 days.
  • Of cases of aseptic meningitis, 3-15% are due to HSV.
  • HSV is the most common cause of recurrent lymphocytic meningitis (Mollaret's meningitis).
• Autonomic dysfunction caused by either HSV or VZV most commonly affects the sacral region, resulting in numbness, tingling of the buttocks or perineal areas, urinary retention, constipation, and impotence.
  • Symptoms take days or weeks to resolve.
  • In rare instances, transverse myelitis or Guillain-Barré syndrome follows HSV infection.

Visceral Infections

HSV infection of visceral organs usually results from viremia; multiple-organ involvement is common, but occasionally only the esophagus, lung, or liver is affected.

• In HSV esophagitis, pts present with odynophagia, dysphagia, substernal pain, weight loss, and multiple oval ulcerations on an erythematous base. Detection of HSV is necessary to distinguish this entity from esophagitis of other etiologies (e.g., Candida esophagitis).
• HSV pneumonitis is rare except among severely immunocompromised pts and results in focal necrotizing pneumonitis with a mortality rate of >80%.
• Hepatic HSV infection occurs primarily in immunocompromised pts and is associated with fever, abrupt elevations of bilirubin and serum aminotransferase levels, and leukopenia (<4000 WBCs/µL).

Neonatal Infections

The frequency of visceral and/or CNS infection is highest among HSV-infected infants <6 weeks of age; the mortality rate without therapy is 65%.

• Infection is usually acquired perinatally from contact with infected genital secretions during delivery.
• Approximately 50-70% of cases are due to HSV-2. The risk is elevated 10-fold for infants born to a mother who has recently acquired HSV.