-IBIS-1.5.0-
tx
cutaneous system
herpes simplex
diagnoses
definition and etiology
definition:
chronic, recurrent viral infection with a typical presentation on the skin or mucous membranes; lesions consist of single or multiple groups of small vesicles filled with serous fluid, on slightly raised erythematous bases which ulcerate; the virus may affect several systems, causing several conditions from minor "cold sores" to frequently fatal encephalitis; "herpes" is from the Greek "to creep" and was used by Herodotus to describe fever blisters in 100 C.E.
etiology:
The virus responsible for the infections is the herpes simplex virus (HSV): HSV 1 causes herpes labialis and keratitis (oral and ocular lesions); HSV 2 causes genital lesions and is considered a sexually transmitted disease passed by contact with the open lesions. It is now thought that HSV 1 and 2 can interchangeably produce oral and/or genital lesions, though the symptoms of HSV 2 are typically more severe. The initial infection is characterized by severe systemic complaints accompanied by local or body-wide cutaneous and/or mucosal lesions; systemic complaints are not present in subsequent recurrences of the lesions. HSV 2 is the most common form of genital ulceration in the U.S. The initial incubation is from 1-26 days (usually 2-7 days after exposure). Following the primary disease the virus is not recoverable from the ganglia or from surface viral proteins: how the virus maintains latency is unknown. Also unknown is how various stimuli reactivate the virus to elicit another infection. Triggers associated with beginning an attack include sunlight, high arginine content in diet, fevers, infections, physical or emotional stress, trauma to the skin, sexual stimulation and immunosuppression.
signs and symptoms
signs and symptoms: general
lesions may appear anywhere on the skin or mucosa; patients usually present with lesions around the mouth, on or just above the lips, on the nose, conjunctiva, cornea, or anywhere on the genitalia (including the cervix); associated lymphadenopathy may be present
a pathognomonic symptom of HSV is a prodromal sensation of tingling or itchiness over the exact area where the lesions later occur (1-2 days); there may also be paresthesias or neuralgic pain in adjacent areas
cluster size may be from .5 cm to 1.5 cm, although groups may merge together
vesicles appear, grow larger (causing pain from pressure), break open to form ulcers, then scab over with a thin, yellowish crust
healing begins after 7-10 days, but it usually takes a full 21 days to completely resolve the sore; lesions on moist body parts heal more slowly
there is usually no scarring or atrophy of the tissue under the lesion, unless lesions recur frequently in the same location
signs and symptoms: specific infections
oral-facial herpes: The primary infection is marked by gingivostomatitis and pharyngitis, and is commonly seen in children and young adults. The patient presents with fever, myalgia, malaise, irritability, refusal to eat, and cervical lymphadenopathy; these may persist for 3-14 days. Oral-facial lesions frequently involve the hard and soft palates, the lips, tongue, gingiva, and entire facial area. Recurrent lesions tend to focus on or above the lips, are less severe, and are not accompanied by systemic symptoms. They will usually be preceded by neuralgia.
genital lesions: Systemic symptoms also include fever, myalgia, malaise and headaches. Genital complaints include pain (can be severe), itching, tender inguinal lymphadenopathy, vaginal and urethral discharge, and dysuria. In women, cervical and urethral involvement is noted in over 80% of the initial infections. Rectal and anorectal herpes are generally seen in homosexual men and/or heterosexual women after anorectal intercourse with an infected partner. Symptoms include tenesmus, anorectal pain, anorectal discharge, and constipation (holding in due to the pain of stool passage). Patients who already have oral-facial herpes may have a less intense primary attack of genital herpes. Recurrences of genital herpes are common, usually within 1-4 months of the first outbreak; the average number of recurrences experienced by genital herpes sufferers is 4-7 episodes a year, preceded by typical prodromal symptoms.
herpetic whitlow: infection of the finger, usually seen in medical practitioners or their support staff; signs and symptoms include fever, edema/erythema/ tenderness of finger, vesicular/pustular lesions of the finger, epitrochlear/ axillary lymphadenopathy, and lymphadenitis
herpetic eye infections: This is the most frequent cause of corneal blindness in the U.S. Patients present with acute onset of pain, chemosis, conjunctivitis, blurring of vision, and the typical dendritic lesions on the cornea, as well as herpetic lesions near or around the eyeball. Although conventional treatment can be effective in healing the involved tissues, recurrences are common and can lead to damage to deeper structures of the eyes.
central nervous system infections: HSV is responsible for 10-20 % of all cases of acute viral encephalitis in the U.S. Diagnostic signs and symptoms include acute onset of fever, and neurologic symptoms (esp. those relating to the temporal lobe). HSV meningitis is an acute, self-limiting disease presenting with headache, mild photophobia, and fever lasting from 2-7 days.
neonatal HSV infection (< 6-7 weeks): Neonates usually acquire the disease as they pass through an infected birth canal, although congenitally acquired cases have been reported where the mother developed a primary infection during pregnancy. Skin lesions are usually present. 70% of untreated neonates will develop CNS involvement. With therapy, the neonatal morbidity from the disease is less than 25%, but less than 10% of neonates with CNS involvement experience normal development.
lab findings:
culture from base of lesion (+)
in primary infections, there will be a progressive increase in the serum antibodies biopsy
amino acid testing for arginine and lysine levels
Tzanck smear of lesion shows multinucleated giant cells
course and prognosis
see entries in "signs and symptoms"
The most common infections are oral or genital lesions; there is no cure for these, and recurrences are common, though their frequency seems to reduce as the years go on.
Conventional physicians treat severe primary attacks with acyclovir. The drug does not effectively alter the rate of recurrence, but appears to reduce severity of attacks, so is indicated in the immune-compromised.
Patients generally experience recurrences until their triggers are uncovered and avoided, or their immune systems are built up to fight off the viral episodes. Outbreaks are infectious from the first prodromal symptoms until the lesions have completely healed over and the scab has disappeared. Patients should use the prodromal periods as a sign for sexual abstinence until the lesions have healed. The vesicular fluid is filled with viral material and is extremely infectious. Sufferers should therefore observe extreme care while cleaning or treating their lesions.
differential diagnosis
genital: trauma; excoriation of non-ulcerative skin lesions (e.g., scabies); squamous cell carcinoma; fixed drug reactions (esp. tetracyclines, methaqualone and barbiturates); ulcerative illnesses involving both the genital and non-genital areas, including psoriasis, pemphigus/pemphigoid, lichen planus, Behcet's syndrome, dermatitis herpetiformis, and erythema multiforme
oral-facial: trauma, aphthous stomatitis
systemic: herpes zoster, varicella
footnotes