Primary Herpes Infection

Primary Herpes Simplex (HSV-I) type 1 produces a viral infection most common in the oral cavity. It occurs most often in children under 6 years, but may involve older patients. In most children primary infection is subclinical (without clinical signs or symptoms), approximately 13% of children had symptomatic herpes by age 9.

The herpes simplex are virtually ubiquitous in the general population, over 90% of adults have antibodies to herpes simplex virus in the fourth decade of life. Once someone is infected, the virus spreads to regional mass of nerve tissue, lymph nodes (eg, trigeminal ganglion) where it remains latent but can be reactivated once the conditions are appropriate.

The causes and course of the disease:

Both types of herpes simplex 1 and 2 may cause the two orofacial, genital infections, but HSV-I is most frequent cause of injuries in and around the mouth, ranging from the relatively trivial to a cold sore vesiculoinflammatory (with small elevations on the skin blisters with fluid in them) eruption. These lesions usually involves large areas of the oral mucosa, moist surface tissues that line the mouth, throat and lips. This condition is called gingivostomatitis.

In addition, herpes simplex virus infection can cause the membranes of the eye, causing keratoconjunctivitis. In infants or immunocompromised (including depressed immune system) adults, the infection can cause internal organs (eg lungs, liver) or produce an encephalitis (brain inflammation) or fatal disseminated disease.

Recurrent herpes infections develop in approximately one third of these patients had a primary infection. Herpes labialis is the most common form of recurrent infection. It is generally regarded as a cluster of blisters that appear around the mouth, after a systemic illness or other stresses fill situation. The ultraviolet and mechanical stimuli may also produce recurrences.

Clinical features

The blister "mouth sores" or "as is well known, is a vesicular lesion usually located around the openings of the mucous membranes like the lips and nose. Often, multiple lesions appear simultaneously or in rapid succession. There is often history of previous respiratory tract infection or fever, exposure to sun or cold, or trauma to the area, but if these influences actually activate the virus remains unclear.

The vesicular lesion begins with a tone of intracellular and intercellular edema followed by ballooning degeneration of epidermal cells and acantholysis (cell separation) with the formation of an intraepithelial vesicle (blister). Individual epidermal cells at the margins of the gallbladder or lying free in the liquid to develop intranuclear inclusions composed of virions, living or dead. Sometimes the fuse to produce more cells polykaryons or giant cells that can be identified in smears of blister fluid (Tzanck preparation). The blisters may burst to produce superficial ulcerations, and in most cases, within a few days are covered with a fibrin clot and heal gradually.

Primary herpetic gingivostomatitis is a more florid herpes infection of the oral cavity that occurs in the immunocompromised host (weakness, impaired immunity, immunosuppressive therapy, and among the very young who have not antibodies). The lips and gums and oral mucosa are involved, but sometimes the language and retropharynx. The individual lesions may begin as vesicles, but may extend to the mucosa and the deep layers of the skin, promoting systemic dissemination. Coalescence of lesions led to the denudation of large areas of the mucosa. There is a proportionate response and a more consistent inflammatory edema and erythema.

The episode's main gingivostomatit herpes.