164 - Herpes Simplex Flashcards
Most prevalent sexually transmitted disease worldwide
Most common cause of ulcerative genital disease
Genital herpes
The incidence of primary infection with HSV-1 is greatest during
Childhood
Acquisition of HSV-2 correlates with
Sexual behavior
Y/N: Most persons infected with HSV-1 or HSV-2 are asymptomatic
Yes
Y/N: Even though HSV-asymptomatic persons shed virus less frequently than symptomatic persons, the amount of HSV-2 shed during asymptomatic shedding is similar in symptomatic and asymptomatic groups
Yes
It is estimated that more than _____% of HSV-2 transmission is associated with asymptomatic shedding
70
As with other sexually-transmitted infections, the rate of acquisition of HSV-2 infection is higher for (men/women)
Women
Asymptomatic HSV-2 infection is more common among
Men
Persons who are also seropositive for HSV-1
(Primary/Recurrent) infections with HSV are usually more severe, frequently involve systemic signs and symptoms, and have a higher rate of complications
Primary
Most commonly affected area in orofacial herpes reactivation
Outer one-third of the lower lip
Stages of classical herpes lesions
Prodromal, erythema, and papule (developmental stage)
Vesicle, ulcer, and hard crust (disease stage)
Dry flaking and residual swelling (resolution stage)
Triggers for oral herpes recurrences
Emotional stress Illness Exposure to sun Trauma Fatigue Menses Chapped lips Season of the year Exposure to UV irradiation Trigeminal nerve surgery Oral trauma Epidural administration of morphine Abrasive laser Chemical facial cosmetic procedures
HSV-2 orolabial infections are 120 times (more/less) likely to reactivate than orolabial HSV-1 disease
Less
Y/N: Acquisition of HSV-1 in a person with prior HSV-2 infection is unusual
Yes
Y/N: HSV-2 acquisition in the presence of previous HSV-1 infection is common
Yes
Infections caused by HSV-2 reactivate approximately 16 times (more/less) frequently than HSV-1 genital infections
More
Average recurrence of HSV-2 genital infections per year
3 to 4 times
Infection of the fingers by HSV acquired by direct inoculation or direct spread from mucosal sites at the time of primary infection
Herpetic whitlow
Y/N: Surgical drainage is often needed for herpetic whitlow
No - unnecessary and potentially harmful
Cutaneous herpes transmitted in wrestling
Herpes gladiatorum
Cutaneous herpes transmitted in rugby
Herpes rugbiorum or scrum pox
Results from widespread infection following inoculation of virus to skin damaged by eczema
Eczema herpeticum (Kaposi varicelliform eruption)
Antimicrobial peptides that inhibit HSV replication
Cathelicidin
Beta-defensins
Mortality in eczema herpeticum was primarily caused by
Bacterial superinfection and bacteremia
Recurrent HSV infection is the most common precipitating event in cases of
Recurrent erythema multiforme
Primary maternal genital herpes is associated with a risk of neonatal infection of _____% for vaginally-delivered babies
25-50
Recurrent maternal HSV infection is associated with a risk of neonatal transmission of less than _____%
3
Neonatal herpes infections manifest in 1 of 3 forms
Skin, eye, and mouth involvement
Encephalitis
Disseminated disease
All HSV infections involve the _____ system
Nervous
HSV encephalitis usually presents with acute focal neurologic symptoms, fever, and involvement of the _____ lobe
Temporal
Most common diagnostic technique for HSV encephalitis
PCR of the cerebrospinal fluid for HSV DNA
Y/N: Recurrent and persistent ulcerative HSV lesions are among the most common and defining opportunistic infections in patients with AIDS
Yes
Constant immune surveillance and engagement are required to maintain latency, mainly by HSV-specific _____ lymphocytes
CD8+
Patients with defects in (cellular/humoral) immunity have no increase in HSV disease severity
Humoral
Only approximately _____% of fresh genital lesions are culture positive
60-70
Isolation of virus is most successful when lesions are cultured
During the vesicular stage
When specimens are taken from immunocompromised patients or from patients suffering from a primary infection
More sensitive than viral isolation
Preferred method for diagnosis
PCR
Enable typing of the isolate as HVS-1 or HSV-2
Viral culture
PCR assays
Tzanck test is positive in fewer than _____% of culture-proven cases
40
Cesarean section delivery may not reliably prevent neonatal HSV infection when
Membranes are ruptured for long periods (24 hours or more)
For women at or beyond _____ of gestation who are at risk for recurrent HSV infection, suppressive antiviral therapy has been recommended
36 weeks
Acyclovir must be phosphorylated to be active, and it requires the viral _____ for phosphorylation
Thymidine kinase
Oral prodrug of acyclovir that achieves 3- to 5-fold higher bioavailability
Valacyclovir
Well absorbed oral form of penciclovir
Famciclovir
Topical cream approved by the US FDA for the treatment of herpes simplex labialis
Penciclovir 1% cream
Approved by the FAD for nonprescription treatment of recurrent herpes labialis
Long-chain saturated alcohol that inhibits entry of lipid-enveloped virus into the cell
Docosanol 10% cream
Treatment of choice for disseminated or severe herpes infections
Intravenous acyclovir 10 to 15 mg/kg every 8 hours
Dose of intravenous acyclovir for neonatal herpes
20 mg/kg per dose given every 8 hours
Most effective management strategy for persons with frequent or complicated genital recurrences
Long-term suppressive therapy with acyclovir or its analogs
Y/N: Suppressive therapy with valacyclovir was more effective to reduce the burden of genital herpes disease than episodic therapy
Yes
Y/N: Orolabial HSV infections warrant the same antiviral treatment as do genital infections
No - warrant antiviral treatment less often
Y/N: Oral infections are inherently briefer and less symptomatic than genital herpes
Yes
Y/N: Creams and ointments containing 5% and 10% acyclovir are not beneficial in recurrent herpes labialis
Yes
Y/N: The use of suppressive acyclovir for recurrent herpes labialis is recommended
No - controversial
Virtually all clinically relevant drug resistance has been seen in
Immunocompromised patients
Effective in the treatment of acyclovir-resistant HSV
Does not require activation by HSV thymidine kinase
Requires IV therapy
Foscarnet
Adverse effects of foscarnet
Nephrotoxicity
Electrolyte disturbances
Anemia
Seizures
Intravenous cidofovir is associated with considerable nephrotoxicity and requires the coadministration of
Saline hydration and probenecid
Treatment for acyclovir-resistant HSV
Foscarnet Cidofovir Imiquimod Resiquimod Continuous IV acyclovir
