Oral Herpes Simplex (Cold Sore)

4.05 Oral Herpes Simplex (Cold Sore)

Presentation
Patients have swelling, burning or soreness at an intra- or extra-oral lesion consisting of clusters of small vesicles on an erythematous base, which then rupture to produce red irregular ulcerations with swollen borders and possibly crusting or superinfection. These lesions occur on the hard palate or gingiva or, more commonly, at the vermilion border of the lip.
What to do:



When there is any doubt of the diagnosis, scrape the base of a vesicle (warn the patient this hurts) smear on a slide, stain with Wright's or Giemsa, and examine for multinucleate giant cells (look for nuclear molding). This is called a Tzanck Prep, and establishes the diagnosis of herpes. Alternatively, this swab can be sent for viral cultures, which may take days to grow.



An equal mixture of Kaopectate and Benadryl elixir will coat and dry the area and reduce pain. Topical Orabase, or Xylocaine 2% Viscous Solution will also relieve the pain. Consider oral analgesics for continuous pain relief. Narcotic analgesics and mild sedation may be required to manage the most severe pain.



Instruct the patient to keep lesions clean, and avoid touching lesions (so as not to spread the virus to eyes, unaffected skin, and other people).



Inform the patient that oral herpes need not be related to genital herpes; that the vesicles and pain should resolve over about two weeks (barring superinfection); that they are infectious during this period (and perhaps other times as well); and that the herpes simplex virus, residing in sensory ganglia, can be expected to cause recurrences from time to time (especially during illness or stress).
What not to do:



Do not prescribe topical or systemic acyclovir (Zovirax) unless the patient or household contacts are immunocompromised. It reduces viral shedding, but has not been shown to benefit oral herpes simplex.



Do not use topical anesthetics on keratinized skin. They are only effective on oral mucosa.
Discussion
Herpes simplex infection may be either primary or recurrent. Possible causes of herpes reactivation include stress, fever, menstruation, gastrointestinal distubance, infection, cold, fatigue and sunlight. Primary herpes usually appears as gingivostomatitis, pharyngitis, or a combination of the two, while recurrent infections usually occur as intraoral or labial ulcers. Primary infection tends to be a disease of children or young adults, more severe than recurring episodes, preceded by fever to 105 degrees, sore throat and headache, and followed by red, swollen gums that bleed easily. This gingivostomatitis may need to be differentiated from herpangina, acute necrotizing ulcerative gingivitis, Stevens-Johnson syndrome, Behet's syndrome and hand, foot and mouth disease.
Herpangina is caused by Coxsackie A virus and involves the posterior pharynx. Acute necrotizing ulcerative gingivitis, also known as Vincent's angina or trench mouth, is bacterial in origin, has characteristic blunting of the interdental gingival papillae, and responds rapidly to penicillin. Steven-Johnson sundrome is a severe form of erythema multiforme. There are characteristic lip lesions, the gingiva is only rarely affected, and there may be bull's-eye skin lesions on the hands and feet. Behet's syndrome is thought to be an autoimmune response and is associated with genital ulcers and inflammatory ocular lesions. Hand, foot and mouth disease is also caused by the Coxsackie A virus and is associated with concurrent lesions of the palms and soles.
 Home remedies for cold sores include ether, lecithin, lysine, and vitamin E. Because herpes is a self-limiting affliction, all of these work, but, in controlled studies, none have outperformed placebos (which also do very well).
References:



Raborn GW, Dip MS, McGaw WT, Grace M, Percy J: Treatment of herpes labialis with acyclovir. Am J Med 1988;85(suppl 2A):39-42

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