Genital Herpes Infections

Diagnostic Methods and Management Strategies of Herpes Simplex and Herpes Zoster Infections

Herpesviruses are medium-sized double-stranded DNA viruses. Of more than 80 herpesviruses identified, only 9 human herpesviruses have been found to cause infection in humans. These include herpes simplex viruses 1 and 2 (HSV-1 and HSV-2), varicella-zoster virus (VZV), human cyto-megalovirus (HCMV), Epstein-Barr virus (EBV), and human herpesvirus (HHV-6A, HHV-6B, HHV-7, HHV-8). HSV-1, HSV-2, and VZV can be problematic given their characteristic neurotropism which is the ability to invade via fusion of its plasma membrane and reside within neural tissue. HSV and VZV primarily infect mucocutaneous surfaces and remain latent in the dorsal root ganglia for a host's entire life. Reactivation causes either asymptomatic shedding of virus or clinical manifestation of vesicular lesions. The clinical presentation is influenced by the portal of entry, the immune status of the host, and whether the infection is primary or recurrent. Affecting 60% to 95% of adults, herpesvirus-associated infections include gingivostomatitis, orofacial and genital herpes,and primary varicella and herpes zoster. Symptomatology, treatment, and potential complications vary based on primary and recurrent infections as well as the patient's immune status.

Human herpes simplex virus infections: epidemiology, pathogenesis, symptomatology, diagnosis, and management

Eight of the more than 80 known herpesviruses are human pathogens. Human herpes simplex virus (HSV) is a contagious infection with a large reservoir in the general population. It has a potential for significant complications in the immunocompromised host. In addition, psychological distress caused by the negative stigma associated with genital herpes and visible facial lesions in those experiencing frequent outbreaks renders it a challenging clinical dilemma. This article reviews the epidemiology, pathogenesis, and diagnostic features of HSV infections, providing the clinician with an up-to-date understanding of the available management strategies for mucocutaneous HSV-induced disease.

Herpetic gingivostomatitis in a 70-year-old man

We report a case of herpetic gingivostomatitis that was remarkable because it occurred in a 70-year-old man. The patient had multiple small ulcers throughout the mouth that were culture-positive for herpes simplex virus type 1 and responded rapidly to acyclovir. Whether this condition was a case of primary herpes or an unusual presentation of secondary disease was not resolved. Nevertheless the case serves as a reminder that age, although it may make a diagnosis seem implausible, does not alone exclude it.

A rapid simple in situ hybridization method for herpes simplex virus employing a synthetic biotin-labeled oligonucleotide probe: a comparison with immunohistochemical methods for HSV detection

We examined 28 paraffin-embedded tissue specimens with histologic evidence of herpes virus infection by in situ hybridization (ISH) utilizing manual capillary action technology (MicroProbe Staining System) and a 21 base synthetic multibiotinylated oligonucleotide probe from the HSV glycoprotein C region. The results were compared to a rapid simple immunohistochemical (IHC) protocol for detection of HSV proteins. HSV was detected by ISH and IHC in all but one specimen which was shown to be positive for varicella zoster virus by direct fluorescent antibody studies. Hybridization signal was confined to the nucleus in all cases. Staining was identified in cells with early as well as late cytopathic effect. IHC produced intense nuclear and/or cytoplasmic signal in infected cells and stained in areas of necrosis which were otherwise spared by ISH. HSV was detected by IHC and/or ISH in 3/5 specimens with histology suggestive of, but not diagnostic for, HSV infection. Both techniques were sensitive and specific for HSV, resulted in rapid detection of the pathogen in routinely processed tissues, and may be useful in cases where the histologic impression is equivocal for HSV infection. ISH for HSV may be preferred because it can identify early HSV infection, which in turn can be treated with antiviral agents.

The reliability of serological tests for the diagnosis of genital herpes: a critique

The reliability and limitations of the currently used routine tests for herpes simplex virus type 2 (HSV-2) antibody in Australia are reviewed. Six case reports illustrate the clinical dangers of overinterpretation of the currently available kits and the need for a readily available specific HSV-2 antibody test. In Sydney, HSV-2 causes approximately 85% of primary genital herpes and > 95% of recurrent genital herpes. Due to the extensive serological cross-reactivity between HSV-1 and HSV-2, currently available "type specific" commercial assays cannot reliably distinguish between the 2. Isolation of herpes simplex virus (HSV) or detection of HSV antigen in vesicle fluid is the preferred diagnostic test but may be overlooked or patients may have no visible lesions. The only accurate techniques for detecting HSV-2 specific antibody are the Western blot assay and an enzymatic immunoassay using glycoprotein G (gG-2), a component of the HSV-2 envelope. These tests, which still are restricted to research laboratories can be used to accurately identify people with previous exposure to HSV-2 (IgG) or to diagnose primary infection where virus isolation has not been performed or is impossible. Current commercially available antibody tests may have extensive cross-reactivity.

The diagnosis of recent herpes simplex virus type 2 genital infections by the simplex-2 test

The prevalence of complement-fixing (CF) antibody against the AG-4 early antigen of herpes simplex virus (HSV) type 2 (HSV-2) was determined in patients with culture confirmed HSV-2 genital herpes and control groups using a commercial HSV-2 early antigen (Simplex-2; Gene Link Australia Ltd). Eighty seven per cent of 39 sera collected between 14 and 28 days after confirmed primary and recurrent HSV-2 infection were positive. In acute sera collected between 2-10 days after onset the Simplex-2 test was negative in all 90 patients with presumed primary infection but positive in 53% of 230 sera from recurrent infection. A specificity of 90-94.5% was obtained by testing 36 patients with recent proven HSV-1 infection and 331 control group patients. The Simplex-2 test may be useful in some cases of culture-negative, clinically suspected genital HSV-2 lesions only when sera are collected between 14-28 days after primary and recurrent infection. Its lack of specificity makes it unsuitable for the routine diagnosis of recent HSV-2 infection in the general population.

Indirect ELISA for the detection of HSV-2 specific IgG and IgM antibodies with glycoprotein G (gG-2)

The glycoprotein G (gG-2) purified from HSV-2 infected cells has been reported to be useful for determination of HSV-2 type-specific antibodies using conventional ELISA formats. This study further confirmed the specificity of gG-2 and demonstrated the feasibility of a specific IgM assay. The gG-2 ELISA was developed to detect HSV-2 specific IgG and IgM antibodies in human sera with high levels of sensitivity and specificity. Of 45 patients with culture-proven recurrent HSV-2 genital infection 44 were reactive for gG-2 IgG. Of 30 sera from patients with culture-proven recent initial HSV-2 genital infection 29 were positive for gG-2 IgM. Three patients with primary HSV-2 genital infection showed gG-2 IgM in the convalescent but not in the acute sera. The IgG- and IgM-gG-2 ELISA showed high specificity. None of 40 sera from children were reactive by either assay. Only one of 94 sera from patients with antibody to herpesviruses other than HSV reacted in the IgG assay but none reacted in the IgM assay. There was no cross-reaction with sera from patients with proven HSV-1 infection with the gG-2 antigen. The results suggest that the IgG assay can be used for demonstration of past HSV-2 infection and the IgM assay for the diagnosis of HSV-2 in neonatal herpes and primary genital herpes, when cultures or rapid diagnostic techniques are unavailable.

Sexually transmitted diseases: viruses and ectoparasites. Committee on Sexually Transmitted Diseases of the American Academy of Dermatology

This review highlights recent developments in the epidemiology, pathogenesis, diagnosis, and treatment of nonbacterial sexually transmitted infections. Genital herpes simplex, anogenital human papillomavirus disease, molluscum contagiosum, pediculosis pubis, and scabies are discussed.

Neonatal herpes simplex virus infection in relation to asymptomatic maternal infection at the time of labor

BACKGROUND AND METHODS

To define the risk factors associated with neonatal acquisition of herpes simplex virus (HSV) infection, we prospectively obtained HSV cultures from the cervix and external genitalia of 15,923 pregnant women in early labor who were without symptoms or signs of genital HSV infection. Follow-up of the women with positive cultures for HSV and their HSV-exposed infants included serologic tests and serial cultures for HSV.

RESULTS

HSV was isolated from 56 of the women (0.35 percent), 18 of whom (35 percent) had serologic evidence of a recently acquired, subclinical first episode of genital HSV infection, and 34 of whom (65 percent) had reactivation of HSV. Neonatal HSV developed in 6 of 18 infants (33 percent) born to the women with a first episode of genital HSV, and in 1 of 34 infants (3 percent) born to the women with reactivation of HSV (P less than 0.01); neonatal HSV also occurred in three of the infants born to the 15,867 women with negative cultures. Neonatal HSV-2 occurred in 1 of 4 infants born to mothers seronegative at delivery for both HSV-1 and HSV-2, in 4 of 12 infants exposed to HSV-2 whose mothers had only HSV-1 antibodies at delivery, and in none of the infants born to 31 women who were HSV-2-seropositive. An increased risk of neonatal HSV was associated with exposure to viral shedding from the cervix and the use of fetal-scalp electrodes.

CONCLUSIONS

Of the asymptomatic women who shed HSV in early labor, about a third have recently acquired genital HSV, and their infants are 10 times more likely to have neonatal HSV than those of women with asymptomatic reactivation of HSV. The presence of maternal antibodies specific to HSV-2 but not HSV-1 appears to reduce the neonatal transmission of HSV-2. Further studies are necessary to determine whether screening and prophylactic treatment are warranted for infants of HSV-2-seronegative mothers who shed HSV-1 or HSV-2 in early labor.