Herpes simplex virus

The patient usually presents to the clinician with full-blown oral and systemic disease, but a history of the mode of onset is helpful in differentiating lesions of primary HSV infection from other acute multiple lesions of the oral mucosa. The incubation period is most commonly 5 to 7 days but may range from 2 to 12 days. Patients with primary oral herpes have a history of generalized prodromal symptoms that precede the local lesions by 1 or 2 days. This information is helpful in differentiating this viral infection from allergic stomatitis or erythema multiforme, in which local lesions and systemic symptoms appear together.These generalized symptoms include fever, headache, malaise, nausea, and vomiting. A negative past history of recurrent herpes labialis and a positive history of direct intimate contact with a patient with primary or recurrent herpes are also helpful in making the diagnosis. Approximately 1 or 2 days after the prodromal symptoms occur, small vesicles appear on the oral mucosa; these are thin-walled vesicles surrounded by an inflammatory base. The vesicles quickly rupture, leaving shallow round discrete ulcers. The lesions occur on all portions of the mucosa. As the disease progresses, several lesions may coalesce, forming larger irregular lesions. An important diagnostic criterion in this disease is the appearance of generalized acute marginal gingivitis. The entire gingiva is edematous and inflamed. Several small gingival ulcers are often present. Examination of the posterior pharynx reveals inflammation, and the submandibular and cervical lymph nodes are characteristically enlarged and tender. On occasion, primary HSV may cause lesions of the labial and facial skin without intraoral lesions.

TREATMENT
Primary HSV in otherwise healthy children is a self-limiting disease. The fever ordinarily disappears within 3 or 4 days, and the lesions begin healing in a week to 10 days, although HSV may continue to be present A significant advance in the management of herpes simplex infections was the discovery of acyclovir, which has no effect on normal cells but inhibits DNA replication in HSV-infected cells.24 Acyclovir has been shown to be effective in the treatment of primary oral HSV in children when therapy was started in the first 72 hours. Acyclovir significantly decreased days of fever, pain, lesions, and viral shedding. Newer antiherpes drugs are now available, including valacyclovir and famciclovir. The advantage of the newer drugs is increased bioavailability, allowing for effective treatment with fewer doses. Milder cases can be managed with supportive care only. The use of antiviral drugs in the management of recurrent disease or in immunocompromised patients is discussed later in this chapter in sections on recurrent and chronic HSV.
Routine supportive measures include aspirin or acetaminophen for fever and fluids to maintain proper hydration and electrolyte balance. If the patient has difficulty eating and drinking, a topical anesthetic may be administered prior to meals. Dyclonine hydrochloride 0.5% has been shown to be an excellent topical anesthetic for the oral mucosa. If this medication is not available, a solution of diphenhydramine hydrochloride 5 mg/mL mixed with an equal amount of milk of magnesia also has satisfactory topical anesthetic properties. Infants who are not drinking because of severe oral pain should be referred to a pediatrician for maintenance of proper fluid and electrolyte balance. Antibiotics are of no help in the treatment of primary herpes infection, and use of corticosteroids is contraindicated. Future therapy may include prevention of the infection with use of a genetically disabled HSV vaccine.