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Identification of Herpes Simplex Virus (HSV) Shedding in the Female Genital Tract of Pregnant and Nonpregnant Women by GeneXpert PCR, Routine PCR, and Culture

Completed
Conditions
Herpes Simplex Virus
Interventions
Device: Genexpert assay
Registration Number
NCT01878383
Lead Sponsor
University of Alabama at Birmingham
Brief Summary

PCR detection of HSV DNA shedding in the female genital tract using the GeneXpert system (Cepheid, Sunnyvale CA) will be compared with traditional (routine) PCR (pregnant and nonpregnant women) and with HSV culture (nonpregnant women). The GeneXpert system performs all sample-processing steps and real-time PCR in a single integrated cartridge. The standard cartridge is an inexpensive disposable plastic cartridge with filtration and ultrasonic lysis capabilities. It consists chiefly of several combined molded plastic components: a cartridge body containing eleven fluid reservoirs or chambers along with an attached PCR tube, a specialized valve body with an ultrasonic interface containing a sub-micron filter and glass lysis beads, and a rotary valve with an axial syringe barrel. The operation of the cartridge is simple. The rotary valve contains an inlet and an outlet port. Fluid such as a sample buffer can be drawn up into a syringe drive through the inlet port of the rotary valve and then dispensed into any other chamber within the cartridge by rotating the valve and expelling the fluid through the outlet port. The fluid can either be passed through a filter contained within the valve assembly or it can be passed directly into the next chamber without filtration, depending on the path that is chosen. The cartridge fluidics and subsequent real-time PCR all are performed within the GeneXpert instrument. The GeneXpert contains multiple modules (ICORE units) that can be independently programmed to drive the syringe/rotary valve, and to perform four-color real-time PCR. Each cartridge fits inside one module, and all processing, PCR, and analysis steps are performed automatically. Each ICORE module can be run and analyzed independently, so batching of samples is unnecessary.

Detailed Description

The GeneXpert HSV PCR test will be validated against HSV viral cultures and routine quantitative PCR. Validation will occur in two populations: 1) nonpregnant women in STI clinics with clinically-apparent HSV lesions (Group 1, n=300), and 2) pregnant women in active labor with no visible evidence of HSV infection (Group 2, n=12,500). All testing of samples on the GeneXpert platform, routine quantitative PCR, and viral culture will be done at the UAB Central Laboratory. Women in each group will have specimens obtained from genital lesions (Group 1) or vaginal swabs (Group 2). Specimens from all women in Group 1 will be evaluated by HSV culture, routine HSV PCR, and GeneXpert HSV PCR. Approximately half of the women in Group 2 will be tested by routine HSV PCR and GeneXpert HSV PCR; specimens from the rest of the women in Group 2 will be stored for possible testing in the future by routine HSV PCR and GeneXpert HSV PCR. In this manner, we will maximize the data from which to compare GeneXpert PCR results with routine PCR, while maintaining flexibility to ensure an adequate number of specimens are positive for HSV DNA by routine PCR.

Swabs from pregnant women in labor will be placed in viral transport media, frozen at -20°C, and batch-shipped to the UAB Central Laboratory for analysis on the GeneXpert instrument and by routine HSV quantitative PCR. Swabs from nonpregnant women in STI clinics will be placed in viral transport media, refrigerated at 4°C, and shipped to the UAB Central Laboratory for real time analysis on the GeneXpert instrument and by HSV culture and routine quantitative HSV PCR. Specimens from the first 300 women enrolled in Group 2 will be run as individual routine PCRs and in batches of 5 samples per PCR run. In this manner, we will validate that the level of detection from batching of samples for routine PCR is acceptable. Once this validation occurs, specimens from the approximately half of remaining Group 2 women will be batched for real-time routine PCR analysis. If a batch run of 5 specimens is negative, no further testing will be performed. If a batch run of 5 specimens is positive, all of the specimens will be separated out for re-running as individual PCRs. All specimens evaluated by routine PCR will also be evaluated by GeneXpert PCR; in this manner, we will have individual routine PCR results results for comparison against GeneXpert PCR results.

A blood specimen will be obtained from each nonpregnant (Group 1) and pregnant (Group 2) woman at the time of enrollment, and if she is determined to be shedding HSV by routine PCR, GeneXpert PCR, or culture then type-specific serologic testing will be performed. Correlation of viral typing from the virologic sampling with HSV-1 and HSV-2 serostatus will allow for categorization of infection (first-episode primary, first-episode nonprimary, or recurrent infection).

Those women in Group 1 who have a positive HSV culture will be contacted directly when the result is known. Women in Group 2 with a positive HSV PCR result will not be contacted because routine HSV PCR and GeneXpert PCR are not FDA-cleared tests in this population; thus, we will not know the test performance characteristics (e.g., sensitivity, specificity, etc.) until completion of the trial. All pregnant women in Group 2 will receive written materials at the time of enrollment educating them on signs and symptoms of neonatal HSV disease. All postpartum women will be contacted by telephone 60-90 days post-delivery and an inquiry will be made to determine if their babies developed neonatal HSV disease.

Data on the incidence of neonatal HSV disease among babies delivered to women in Group 2 will be compared with the incidence data from Brown et al.1 In their study of almost 60,000 women conducted over a 20 year period, this group of researchers has reported an incidence rate for neonatal HSV disease of 1 in 3,200 live births.

Recruitment & Eligibility

Status
COMPLETED
Sex
Female
Target Recruitment
12550
Inclusion Criteria

•Signed Informed Consent from woman

•≥ 19 years of age

  • Female gender
  • In active labor with a viable fetus, OR non-pregnant and being evaluated in STI clinics for herpetic genital lesions
Read More
Exclusion Criteria

•For women in active labor, active herpetic lesions in the genital region

  • Receipt of acyclovir, valacyclovir, or famciclovir within the previous 14 days
  • Known HIV infection
Read More

Study & Design

Study Type
OBSERVATIONAL
Study Design
Not specified
Arm && Interventions
GroupInterventionDescription
Non-pregnant women/active HSV lesionsGenexpert assayWomen presenting to local health department
Pregnant women/no active HSV lesionsGenexpert assayWomen presenting in active labor
Primary Outcome Measures
NameTimeMethod
Sensitivity of Detection of HSV DNA by GeneXpert PCR From Specimens Obtained From the Genital Tract of Non-pregnant Women in STI Clinics, as Compared With HSV Cultureon day of enrollment

Assessing the vaginal specimen collected via a swab of non-pregnant women presenting to their provider at the time of active HSV outbreak with standard HSV culture compared to the assay of new device called a GeneXpert.

Percent of GeneXpert assessment in agreement with standard HSV culture, for subjects who were positive for HSV according to culture.

Positive Percent Agreement of Detection of HSV DNA by GeneXpert PCR From Specimens Obtained From Genital Tract of Pregnant Women, as Compared With Routine PCR Detection of Viral DNADAY OF ENROLLMENT

Detection of HSV DNA by GeneXpert PCR compared to routine PCR detection by viral DNA. Percent of GeneXpert assessment in agreement with routine PCR detection, for subjects who are positive for HSV according to routine PCR.

Negative Percent Agreement of Detection of HSV DNA by GeneXpert PCR From Specimens Obtained From Genital Tract of Pregnant Women, as Compared With Routine PCR Detection of Viral DNADAY OF ENROLLMENT

Detection of HSV DNA by GeneXpert PCR compared to routine PCR detection by viral DNA. Percent of GeneXpert assessments in agreement with routine PCR detection, for subjects who were negative for HSV according to routine PCR.

Secondary Outcome Measures
NameTimeMethod

Trial Locations

Locations (15)

Louisiana State University Health Science Center-Shreveport

🇺🇸

Shreveport, Louisiana, United States

University of Colorado at Denver Health Sciences Center

🇺🇸

Aurora, Colorado, United States

University of Rochester Medical Center

🇺🇸

Rochester, New York, United States

Children's National Medical Center

🇺🇸

Washington, District of Columbia, United States

MetroHealth Medical Center

🇺🇸

Cleveland, Ohio, United States

University of Utah School of Medicine

🇺🇸

Salt Lake City, Utah, United States

Emory Children's Center

🇺🇸

Atlanta, Georgia, United States

Steven & Alexandra Cohen Children's Medical Center of New York (CCMC)

🇺🇸

Manhasset, New York, United States

Nationwide Children Hospital

🇺🇸

Columbus, Ohio, United States

Dartmouth Medical School

🇺🇸

Lebanon, New Hampshire, United States

Carolinas Medical Center - Charlotte

🇺🇸

Charlotte, North Carolina, United States

Washington University in St Louis School of Medicine

🇺🇸

Saint Louis, Missouri, United States

McGee Women's Hospital

🇺🇸

Pittsburgh, Pennsylvania, United States

University of Alabama at Birmingham

🇺🇸

Birmingham, Alabama, United States

University of Arkansas for Medical Sciences

🇺🇸

Little Rock, Arkansas, United States

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