Hybrid Capture Assay Research Articles

Interlaboratory Reproducibility and Proficiency Testing within the Human Papillomavirus Cervical Cancer Screening Program in Catalonia, Spain

In Catalonia, a screening protocol for cervical cancer, including human papillomavirus (HPV) DNA testing using the Digene Hybrid Capture 2 (HC2) assay, was implemented in 2006. In order to monitor interlaboratory reproducibility, a proficiency testing (PT) survey of the HPV samples was launched in 2008. The aim of this study was to explore the repeatability of the HC2 assay's performance. Participating laboratories provided 20 samples annually, 5 randomly chosen samples from each of the following relative light unit (RLU) intervals: <0.5, 0.5 to 0.99, 1 to 9.99, and ≥10. Kappa statistics were used to determine the agreement levels between the original and the PT readings. The nature and origin of the discrepant results were calculated by bootstrapping. A total of 946 specimens were retested. The kappa values were 0.91 for positive/negative categorical classification and 0.79 for the four RLU intervals studied. Sample retesting yielded systematically lower RLU values than the original test (P<0.005), independently of the time elapsed between the two determinations (median, 53 days), possibly due to freeze-thaw cycles. The probability for a sample to show clinically discrepant results upon retesting was a function of the RLU value; samples with RLU values in the 0.5 to 5 interval showed 10.80% probability to yield discrepant results (95% confidence interval [CI], 7.86 to 14.33) compared to 0.85% probability for samples outside this interval (95% CI, 0.17 to 1.69). Globally, the HC2 assay shows high interlaboratory concordance. We have identified differential confidence thresholds and suggested the guidelines for interlaboratory PT in the future, as analytical quality assessment of HPV DNA detection remains a central component of the screening program for cervical cancer prevention.

Comparison of Digene Hybrid Capture 2, GeneMatrix PapilloScreen, and a PCR sequencing assay in detecting high-risk and probable high-risk oncogenic HPV genotypes in specimens from Korean women

Most cervical cancers are caused by 15 high-risk (HR) and three probable high-risk (pHR) oncogenic types of human papillomavirus (HPV). However, current commercial HR HPV screening test products do not include pHR HPV genotypes. Recently, PapilloScreen has been developed to detect the 15 HR and three pHR HPV types. In this study, we evaluated the concordance levels and clinical performance of Hybrid Capture 2 (HC2), PapilloScreen, and a PCR sequencing assay in detecting HR and pHR HPV. The PapilloScreen (96.8 %) and PCR sequencing assay (96.8 %) demonstrated higher sensitivity than HC2 (80.7 %) for detecting HR and pHR HPV. The three assays showed similar specificities and positive or negative predictive values. The concordance levels were 86.5 % (κ = 0.68) and 86.5 % (κ = 0.67) between HC2 and PapilloScreen and between HC2 and PCR sequencing, respectively. A near-perfect concordance was observed between PapilloScreen and PCR sequencing (97.8 %, κ = 0.95). Overall, the agreement between the three assays suggests that the results obtained by the HC2 assay are more often discordant (12.6 %) than the PCR-based tests. In conclusion, PapilloScreen is highly sensitive for detecting high-grade CIN or cervical cancer. The PapilloScreen assay should be considered an accurate and sensitive method for detecting HR and pHR HPV infections and an epidemiological tool for prevalence studies as well as early diagnosis and intervention in HR and pHR HPV infections.

Hybrid Capture 2 Assay Based Evaluation of High-Risk HPV Status in Healthy Women of North-East India

High risk HPV (HR-HPV) testing has been recommended as an effective tool along with cytology screening in identification of cervical intraepithelial lesions (CINs) and prevention of their progress towards invasive cervical cancer. The aim of this study was to assess the HR-HPV DNA status by Hybrid Capture 2 (HC2) assay in healthy asymptomatic women of North-East India. This study examined cervical cell samples of forty three (n=43) healthy women by HC2 assay. A High Risk HPV DNA kit (Qiagen) was used which can detect 13 high risk HPV types: 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59 and 68. The mean relative light units (RLU) for samples was in the range of 141-5, 94, 619. HR-HPV DNA was confirmed in 16% (7/43) of participant women samples. Among demographic and clinical parameters, menstrual irregularity (p=0.039) and infection history (p=0.028) has shown statistically significant differences between the HR-HPV-positive and negative groups. In the HR-HPV positive group, two women were confirmed for CINs after colposcopy and histopathologic examination. We suggest that there may be an association between irregular menstruation and infection history of the urogenital tract with HR-HPV DNA prevalence in North-East Indian asymptomatic women. HC2 assay can be a valuable tool for HR-HPV screening.

Comparison of the Anyplex II HPV28 assay with the Hybrid Capture 2 assay for the detection of HPV infection

BackgroundHuman papillomavirus (HPV) testing is an important part of cervical cancer screening and management of women with abnormal cytology results. The Hybrid Capture 2 (HC2) has been recommended for use as a reference test. ObjectiveTo evaluate a new real-time PCR assay (Anyplex II HPV28) for detecting high risk (HR) HPV and to compare it to the HC2. In addition, we compared the genotyping results of the Anyplex II HPV28 to those of sequencing analysis. Study designA total of 1114 cervical swab specimens were consecutively obtained from a single healthcare center. We submitted all specimens for HPV detection with Anyplex II HPV28 and HC2, then analyzed the discordant results using multiplex PCR followed by direct sequencing. ResultsHC2 detected 72 (6.5%) cases with HR HPV, while Anyplex II HPV28 identified 138 (12.4%) cases. The overall agreement rate was 91.4% (1018/1114) of cases. Discordant results between these two assays were observed in 96 cases; 15 were positive only by HC2, and 81 were positive only by Anyplex II HPV28. Sequencing analyses performed in 80 cases of discordant results revealed 11 false-positive, and 67 false-negative results using HC2 tests and two false-positive results using Anyplex II HPV28. ConclusionsThe Anyplex II HPV28 assay is analytically more sensitive in the detection of the 13 HR types represented by the HC2 assay and exhibited a higher concordance with comprehensive genotyping based on the sequencing analysis, and it could be used as a laboratory testing method for identifying HPV genotypes.

HPV testing with cytology triage for cervical cancer screening in routine practice

The purpose of this study was to evaluate the feasibility and effectiveness of Viral Testing Alone with Pap (Papanicolaou) Triage for Screening Cervical Cancer in Routine Practice (VASCAR) in a publicly funded university-affiliated hospital in Montreal, Canada. Women who are 30-65 years old are screened with the Hybrid Capture-2 assay. Women with negative results are retested at 3-year intervals; women with positive results are triaged with conventional cytologic methods. Women with Papanicolaou positive test results (≥atypical squamous cells of undetermined significance) are referred to colposcopy; women with Papanicolaou negative test results are retested with Hybrid Capture-2 assay and a Papanicolaou test in 1 year. Results were compared with a historic era (annual cytology with ≥atypical squamous cells of undetermined significance threshold for colposcopy referral) in the 3 years before VASCAR. VASCAR included 23,739 eligible women, among whom 1646 women (6.9%) tested positive for the human papillomavirus (HPV). Because of the need for subsequent sampling for cytologic testing, follow-up evaluation for cytologic triage was relatively poor; only 46% and 24% of HPV-positive women were Papanicolaou-triaged and underwent biopsy, respectively. Protocol violations occurred mainly in the early phases of implementation (12%). Detection of high-grade cervical intraepithelial neoplasia increased nearly 3-fold (rate ratio, 2.78; 95% confidence interval [CI], 2.1-3.7) during VASCAR, mostly because of a doubling in the rate of high-grade cervical intraepithelial neoplasia (34.0%; 95% CI, 21.2-48.8) compared with the historic cytology-only era (16.3%; 95% CI, 13.2-19.8). VASCAR reduced the median time to colposcopy from a positive screen from 11 months (95% CI, 10.48-11.50) to 3 months (95% CI, 2.64-3.80). VASCAR is feasible; however, it requires cosampling for HPV and cytology and for continuous education of healthcare providers of the HPV-Papanicolaou triage protocol. Efficacy in disease detection and reduction in time to colposcopy referrals compared with the historic cytology era is encouraging but should be considered preliminary because of the small number of patients who were tested.

Reply to triage of women with minor abnormal cervical cytology: Meta‐analysis of the accuracy of an assay targeting messenger ribonucleic acid of 5 high‐risk human papillomavirus types

BACKGROUND High-risk human papillomavirus (hrHPV) DNA detection is generally accepted for the triage of women with a cytologic diagnosis of atypical squamous cells of undetermined significance (ASC-US). However, no consensus has been reached on the optimal management of low-grade squamous intraepithelial lesions (LSIL). METHODS In this meta-analysis, the diagnostic accuracy of nucleic acid sequence-based amplification (NASBA) detection of messenger ribonucleic acid (mRNA) of 5 hrHPV types (the PreTect HPV-Proofer and NucliSENS EasyQ tests) for detecting grade 2 cervical intraepithelial neoplasia or worse (CIN2+) and CIN3+ was assessed in women who had a diagnosis of ASC-US and LSIL. The results were compared with the Hybrid Capture-2 (HC2) assay, which detects the DNA of 13 hrHPV types. A bivariate random-effect model that incorporated the intrinsic correlation between the true-positive and false-positive rates was used for a pooled meta-analysis. RESULTS Considering underlying CIN2+, the pooled absolute sensitivity of the 10 included studies was 75.4% (95% confidence interval [CI], 68.1%-82.7%) and 76.2% (95% CI, 68.3%-76.9%) for the triage of ASC-US and LSIL, respectively. The pooled absolute specificity to exclude CIN2+ was 77.9% (95% CI, 70.1%-85.7%) and 74.2% (95% CI, 69.5%-78.8%) in women with ASC-US and LSIL, respectively. Five studies allowed direct comparison of the mRNA assays with HC2. Considering CIN2+ in women with ASC-US and LSIL, mRNA testing was substantially more specific than the HC2 assay (ratio: 1.98 and 3.36, respectively; P < .001) but was less sensitive (ratio: 0.80 and 0.74, respectively; P < .001). CONCLUSIONS HPV assays for detecting the mRNA of 5 hrHPV types may reduce the over-diagnosis of women who have minor cytologic abnormalities. However, given the lower sensitivity, women with negative mRNA test results cannot be considered free of CIN2+ and require further surveillance. Cancer (Cancer Cytopathol) 2013;121:675–687. © 2013 American Cancer Society.

High‐risk human papilloma virus management in pregnancy with cervical intraepithelial neoplasia during pregnancy and postpartum in China

To investigate the relationship between cervical intraepithelial neoplasia (CIN) and high-risk human papilloma virus (HR-HPV) during pregnancy and postpartum in China. In this prospective case-control study, 168 pregnant women with CIN and cervicitis were diagnosed by colposcopic cervical biopsy. All the cases underwent hybrid capture assay version II (HCII) to detect HR-HPV DNA load amounts and the tests were completed in 3-6 months after childbirth. During pregnancy: as the CIN grade increased, the HR-HPV infection rates increased (P = 0.002), but HR-HPV DNA load amounts (in logarithms) did not change obviously (P = 0.719). 3-6 months postpartum: as the CIN grade increased, the natural negative rate of HR-HPV decreased (P = 0.000), while the amount of HR-HPV DNA (in logarithms) increased (P = 0.036); especially the amount of HR-HPV DNA in pregnant women with CINIII was significantly higher than that of other grades. During pregnancy and 3-6 months postpartum : the amount of HR-HPV DNA (in logarithms) during pregnancy was higher than that of 3-6 months postpartum with the same grade of CIN. The findings emphasize the importance of undergoing the HCII test 3-6 months postpartum. It should be noted that HR-HPV may turn negative in pregnancy with CINIII 3-6 months after childbirth. Further treatments of pregnancy with CIN should be considered according to the CIN grade diagnosed by cervical biopsy via colposcopy 3-6 months after birth, but not according to the persistence of HR-HPV during pregnancy.

Comparative study of the cervista and hybrid capture 2 methods in detecting high‐risk human papillomavirus in cervical lesions

High-risk human papillomavirus (HR HPV) testing is important for the follow-up of patients with cytological abnormalities. This study was undertaken to compare the clinical value of the Cervista and hybrid capture 2 (HC2) tests for detection of HR HPV in cervical lesions. Overall 439 cervical specimens with abnormal cytology and 22 normal cervical specimens were subjected to the Cervista and HC2 tests. HPV positivity and its predictive value for high-grade cervical lesions were assessed. The Cervista and HC2 tests showed comparable HR HPV detection rates in women with all cytological and histological diagnoses, with a positive and negative percent agreement of 90.8% and 64.5%, respectively. The two methods had a same sensitivity of 90% in detecting CIN II or greater cervical lesions, while the specificity for the Cervista test and HC2 assay was 47% and 43%, respectively. The positive rate for the Cervista assay probe set A9 increased with the histological severity, ranging from 25.0% in normal specimens to 69.5% in high-grade lesions. In conclusion, the clinical performance for the Cervista test is as excellent as the HC2 test in detecting HR HPV and predicting high-grade cervical lesions.

Triage of women with minor abnormal cervical cytology: Meta‐analysis of the accuracy of an assay targeting messenger ribonucleic acid of 5 high‐risk human papillomavirus types

High-risk human papillomavirus (hrHPV) DNA detection is generally accepted for the triage of women with a cytologic diagnosis of atypical squamous cells of undetermined significance (ASC-US). However, no consensus has been reached on the optimal management of low-grade squamous intraepithelial lesions (LSIL). In this meta-analysis, the diagnostic accuracy of nucleic acid sequence-based amplification (NASBA) detection of messenger ribonucleic acid (mRNA) of 5 hrHPV types (the PreTect HPV-Proofer and NucliSENS EasyQ tests) for detecting grade 2 cervical intraepithelial neoplasia or worse (CIN2+) and CIN3+ was assessed in women who had a diagnosis of ASC-US and LSIL. The results were compared with the Hybrid Capture-2 (HC2) assay, which detects the DNA of 13 hrHPV types. A bivariate random-effect model that incorporated the intrinsic correlation between the true-positive and false-positive rates was used for a pooled meta-analysis. Considering underlying CIN2+, the pooled absolute sensitivity of the 10 included studies was 75.4% (95% confidence interval [CI], 68.1%-82.7%) and 76.2% (95% CI, 68.3%-76.9%) for the triage of ASC-US and LSIL, respectively. The pooled absolute specificity to exclude CIN2+ was 77.9% (95% CI, 70.1%-85.7%) and 74.2% (95% CI, 69.5%-78.8%) in women with ASC-US and LSIL, respectively. Five studies allowed direct comparison of the mRNA assays with HC2. Considering CIN2+ in women with ASC-US and LSIL, mRNA testing was substantially more specific than the HC2 assay (ratio: 1.98 and 3.36, respectively; P < .001) but was less sensitive (ratio: 0.80 and 0.74, respectively; P < .001). HPV assays for detecting the mRNA of 5 hrHPV types may reduce the over-diagnosis of women who have minor cytologic abnormalities. However, given the lower sensitivity, women with negative mRNA test results cannot be considered free of CIN2+ and require further surveillance.

P3.047 Oncogenic HPV Prevalence in HIV Infected Women Assisted in Public Health in BUENOS AIRES (CABA)

<h3>Background</h3> The scientific evidence shows that HIV-infected women have increased risk of precancerous lesions than uninfected women. The objective was search the prevalence of HPV and assess the cyto-colposcopic and Hybrid Capture test correlation for high-risk HPV in HIV infected women in CABA. <h3>Methods</h3> 269 HIV infected women over 18, not pregnant and without IGT lesions were included between October 2010 to July 2012. Clinical and gynaecological chart were reviewed and sampling for PAP, colposcopy and screening of high-risk HPV were performed. The detection of high-risk HPV was performed with the hybrid capture assay (Digene). <h3>Results</h3> Prevalence of HPV and epidemiological profile were available in the 269 women. 45% had HIV VL below 50 copies and 80% had CD4 upper than 350 cells/cc. A PAP in the last year before this study was available in 30% of cases. The correlation of screening techniques with the three methods proposed: diagnostic cytology, capture hybrid and colposcopy was made in 169 women Prevalence of HPV infection was 39% (104 positive/165 negative). Correlation between Cyto-colposcopic and Hybrid Capture test was: hybrid capture (-) cytology/colposcopy (+) = 2/169 hybrid capture (+) cytology/colposcopy (-) = 15/169 hybrid capture (+) cytology/colposcopy = 32/169 hybrid Capture (-) cytology colposcopy (-) = 84/169 hybrid Capture (+) indeterminate cytology and colposcopy (-) = 19/169 hybrid Capture (-) indeterminate cytology and colposcopy (-) = 17/169 <h3>Conclusions</h3> Despite that it was not a large sample, the negative predictive value of hybrid captures for HPV detection was 98% in this population. We recommend the incorporation of the hybrid capture as screening technique in all women with HIV regardless of the age and all those with negative cytology and positive hybrid capture for the early detection of cervical lesions.

Comparison of the analytical and clinical performances of Abbott RealTime High Risk HPV, Hybrid Capture 2, and DNA Chip assays in gynecology patients

The detection of high-risk (HR) HPV in cervical cancer screening is important for early diagnosis of cervical cancer or pre-cancerous lesions. We evaluated the analytical and clinical performances of 3 HR HPV assays in Gynecology patients. A total of 991 specimens were included in this study: 787 specimens for use with a Hybrid Capture 2 (HC2) and 204 specimens for a HPV DNA microarray (DNA Chip). All specimens were tested using an Abbott RealTime High Risk HPV assay (Real-time HR), PGMY PCR, and sequence analysis. Clinical sensitivities for severe abnormal cytology (severe than high-grade squamous intraepithelial lesion) were 81.8% for Real-time HR, 77.3% for HC2, and 66.7% for DNA Chip, and clinical sensitivities for severe abnormal histology (cervical intraepithelial neoplasia grade 2+) were 91.7% for HC2, 87.5% for Real-time HR, and 73.3% for DNA Chip. As compared to results of the sequence analysis, HC2, Real-time HR, and DNA Chip showed concordance rates of 94.3% (115/122), 90.0% (117/130), and 61.5% (16/26), respectively. The HC2 assay and Real-time HR assay showed comparable results to each other in both clinical and analytical performances, while the DNA Chip assay showed poor clinical and analytical performances. The Real-time HR assay can be a good alternative option for HR HPV testing with advantages of allowing full automation and simultaneous genotyping of HR types 16 and 18.

Human papillomavirus testing versus repeat cytology for triage of minor cytological cervical lesions.

Atypical squamous cells of undetermined significance (ASCUS) and low-grade squamous intra-epithelial lesions (LSIL) are minor lesions of the cervical epithelium, detectable by cytological examination of cells collected from the surface of the cervix of a woman.Usually, women with ASCUS and LSIL do not have cervical (pre-) cancer, however a substantial proportion of them do have underlying high-grade cervical intra-epithelial neoplasia (CIN, grade 2 or 3) and so are at increased risk for developing cervical cancer. Therefore, accurate triage of women with ASCUS or LSIL is required to identify those who need further management.This review evaluates two ways to triage women with ASCUS or LSIL: repeating the cytological test, and DNA testing for high-risk types of the human papillomavirus (hrHPV) - the main causal factor of cervical cancer. Main objective To compare the accuracy of hrHPV testing with the Hybrid Capture 2 (HC2) assay against that of repeat cytology for detection of underlying cervical intraepithelial neoplasia of grade 2 or worse (CIN2+) or grade 3 or worse (CIN3+) in women with ASCUS or LSIL. For the HC2 assay, a positive result was defined as proposed by the manufacturer. For repeat cytology, different cut-offs were used to define positivity: Atypical squamous cells of undetermined significance or worse (ASCUS+), low-grade squamous intra-epithelial lesions or worse (LSIL+) or high-grade squamous intra-epithelial lesions or worse (HSIL+).Secondary objective To assess the accuracy of the HC2 assay to detect CIN2+ or CIN3+ in women with ASCUS or LSIL in a larger group of reports of studies that applied hrHPV testing and the reference standard (coloscopy and biopsy), irrespective whether or not repeat cytology was done. We made a comprehensive literature search that included the Cochrane Register of Diagnostic Test Accuracy Studies; the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library), MEDLINE (through PubMed), and EMBASE (last search 6 January 2011). Selected journals likely to contain relevant papers were handsearched from 1992 to 2010 (December). We also searched CERVIX, the bibliographic database of the Unit of Cancer Epidemiology at the Scientific Institute of Public Health (Brussels, Belgium) which contains more than 20,000 references on cervical cancer.More recent searches, up to December 2012, targeted reports on the accuracy of triage of ASCUS or LSIL with other HPV DNA assays, or HPV RNA assays and other molecular markers. These searches will be used for new Cochrane reviews as well as for updates of the current review. Studies eligible for inclusion in the review had to include: women presenting with a cervical cytology result of ASCUS or LSIL, who had undergone both HC2 testing and repeat cytology, or HC2 testing alone, and were subsequently subjected to reference standard verification with colposcopy and colposcopy-directed biopsies for histologic verification. The review authors independently extracted data from the selected studies, and obtained additional data from report authors.Two groups of meta-analyses were performed: group I concerned triage of women with ASCUS, group II concerned women with LSIL. The bivariate model (METADAS-macro in SAS) was used to assess the absolute accuracy of the triage tests in both groups as well as the differences in accuracy between the triage tests. The pooled sensitivity of HC2 was significantly higher than that of repeat cytology at cut-off ASCUS+ to detect CIN2+ in both triage of ASCUS and LSIL (relative sensitivity of 1.27 (95% CI 1.16 to 1.39; P value < 0.0001) and 1.23 (95% CI 1.06 to 1.4; P value 0.007), respectively. In ASCUS triage, the pooled specificity of the triage methods did not differ significantly from each other (relative specificity: 0.99 (95% CI 0.97 to 1.03; P value 0.98)). However, the specificity of HC2 was substantially, and significantly, lower than that of repeat cytology in the triage of LSIL (relative specificity: 0.66 (95% CI 0.58 to 0.75) P value < 0.0001). HPV-triage with HC2 can be recommended to triage women with ASCUS because it has higher accuracy (significantly higher sensitivity, and similar specificity) than repeat cytology. When triaging women with LSIL, an HC2 test yields a significantly higher sensitivity, but a significantly lower specificity, compared to a repeat cytology. Therefore, practice recommendations for management of women with LSIL should be balanced, taking local circumstances into account.

Primary Cervical Cancer Screening and Triage Using an mRNA Human Papillomavirus Assay and Visual Inspection

Mexican Cervical Cancer Screening Study II (MECCS II) seeks to develop a highly sensitive and highly specific screening program able to be adapted to all socioeconomic levels in Mexico. The objectives of MECCS II are (1) to compare the sensitivity and specificity for cervical intraepithelial neoplasia (CIN) 3 or cancer of self-collected vaginal specimens tested for high-risk types of the human papillomavirus (HR-HPV) by APTIMA with those tested for HR-HPV by Hybrid Capture 2 (HC2); and (2) determine the efficacy of cryotherapy in the treatment of HR-HPV-positive and acetic acid-aided visual inspection (VIA)-positive and -negative women after VIA triage. The study was conducted in rural Mexico. Women aged 30 to 50 years, nonpregnant, with no history of hysterectomy or pelvic irradiation and varied histories of screening, participated. A direct endocervical sample was tested for cytology, HC2, and APTIMA assay (AHPV). Subjects positive on any test were recalled for triage VIA, biopsies, and immediate cryotherapy. Tests were compared using McNemar test. Two thousand forty-nine patients have complete results. Mean age of the patients was 39.2 years; 7.7% presented with ≥atypical squamous cells of uncertain significance (ASCUS), 1.8% ≥low-grade squamous intraepithelial neoplasia, and 0.5% ≥high-grade squamous intraepithelial neoplasia. Two percent of patients had ≥CIN2, and 0.78% had ≥CIN3 (including 2 with invasive disease). The sensitivity of ThinPrep (>ASCUS), HC2, and AHPV for >CIN3 for direct endocervical collection was 87.5%, 100%, and 100%, respectively. The specificity of ThinPrep (>ASCUS), HC2, and AHPV for >CIN3 was 94.1%, 92.2%, and 93.5%, respectively. Specificities of HC2 and AHPV differed significantly. The overall percentage of agreement among HPV assays (HC2 vs APTIMA) is 97%. Four hundred sixty-nine women returned for VIA. Two hundred ninety-one women were treated with cryotherapy. The specificity of the APTIMA assay along with high sensitivity is an advantage for primary screening. Follow-up evaluation will be important to determine the true impact of potential undertreatment in the screening algorithm. Self-sampling applications are explored.

Comparison of Hybrid Capture 2 Assay with Real-time-PCR for Detection and Quantitation of Hepatitis B Virus DNA.

ABSTRACTBackground Both real-time-polymerase chain reaction (PCR) and hybrid capture 2 (HC2) assay can detect and quantify hepatitis B virus (HBV) DNA. However, real-time-PCR can detect a wide range of HBV DNA, while HC2 assay could not detect lower levels of viremia. The present study was designed to detect and quantify HBV DNA by real-time-PCR and HC2 assay and compare the quantitative data of these two assays.Materials and methods A cross-sectional study was conducted in between July 2010 and June 2011. A total of 66 serologically diagnosed chronic hepatitis B (CHB) patients were selected for the study. Real-time-PCR and HC2 assay was done to detect HBV DNA. Data were analyzed by statistical Package for the social sciences (SPSS).Results Among 66 serologically diagnosed chronic hepatitis B patients 40 (60.61%) patients had detectable and 26 (39.39%) had undetectable HBV DNA by HC2 assay. Concordant results were obtained for 40 (60.61%) out of these 66 patients by real-time-PCR and HC2 assay with mean viral load of 7.06 ± 1.13 log10 copies/ml and 6.95 ± 1.08 log10 copies/ml, respectively. In the remaining 26 patients, HBV DNA was detectable by real-time-PCR in 20 patients (mean HBV DNA level was 3.67 ± 0.72 log10 copies/ml. However, HBV DNA could not be detectable in six cases by the both assays. The study showed strong correlation (r = 0.915) between real-time-PCR and HC2 assay for the detection and quantification of HBV DNA.Conclusion HC2 assay may be used as an alternative to real-time-PCR for CHB patients.How to cite this article: Majid F, Jahan M, Moben AL, Tabassum S. Comparison of Hybrid Capture 2 Assay with Real-time-PCR for Detection and Quantitation of Hepatitis B Virus DNA. Euroasian J Hepato-Gastroenterol 2014;4(1):31-35.

Evaluation of the hologic gen-probe aptima HPV assay with the panther system

The Royal Prince Alfred Hospital (RPAH) receives gynecological samples from previously clinically screened high risk patients. In February 2012 the Microbiology Department at RPAH evaluated the APTIMA HPV (AHPV) assay on the fully automated PANTHER system. This assay is a target amplification nucleic acid probe test that utilises target capture for the qualitative detection of E6/E7 viral messenger RNA (mRNA) from 14 high-risk HPV types. The E6 and E7 genes from high-risk genotypes are known oncogenes. 201 ThinPrep specimens were tested in parallel using the Digene Hybrid Capture 2 (HC2) HPV DNA assay and AHPV assay. The results from each assay were directly compared to each other. Cytological and/or histological findings were used to aid resolution of discordant results. The overall agreement between the assays was 92.4%. The sensitivity specificity, positive predictive value and negative predictive value were as follows: for the AHPV assay, 97.1%, 96.9%, 94.3% and 98.4%; and for the HC2 assay, 91.2%, 97.7%, 95.4% and 95.5%. In this small sample size study of tertiary referral samples, the AHPV assay demonstrated good clinical performance. The PANTHER, which is a random access instrument capable of performing up to four different assays at one time, has very significant workflow advantages in comparison with the HC2 assay.

Risk assessment and clinical impact of liquid-based cytology, oncogenic human papillomavirus (HPV) DNA and mRNA testing in primary cervical cancer screening (The FASE Study)

ObjectiveNew commercial HPV RNA assays require further validation studies in population-based cervical cancer screening settings.To assess the performance of (FDA-approved) APTIMA® HPV Assay (AHPV), Hybrid Capture 2 (HC2), in-house PCR genotyping, and ThinPrep LBC in population-based screening, stratified by three histological gold standards. Study designA multi-center trial in 5006 women undergoing routine screening in France was designed to compare the absolute and relative risks of diagnosing CIN3+ and CIN2+ lesions by different diagnostic tests. ResultsReproducibility between the primary and second pathology reading was excellent for CIN3+ and CIN2+ endpoints (Cohen's kappa 0.948 and 0.854). Absolute risks (PPV) of different tests (AHPV, HC2, PCR genotyping, LBC) in diagnosing CIN2+ (15–20%) and CIN3+ (4–6%) were similar for the first, second, and consensus pathology readings. The relative risks of diagnosing these lesions by the four tests were also similar when the first, second or third pathology readings were employed. AHPV had the highest absolute risk of both histological endpoints, and detects 5% to 15% more CIN3+ and CIN2+ lesions, respectively, than LBC. Compared with HC2 assay, the relative risk of AHPV is 24% to 29% higher, with a significant difference in CIN2+ detection. With LBC as reference, AHPV had the best sensitivity/specificity balance measured by AUC (area under ROC curve) comparison test (significant for CIN2+), and the colposcopy referral rate (9.2%) comparable to that of LBC (8.7%). ConclusionsThese data corroborate the suitability of AHPV for the primary cervical cancer screening.

Human papillomavirus viral load in cervical intraepithelial neoplasia as a prognostic factor in a Mexican population

Persistent infection with human papillomavirus (HPV) has been recognized as the main etiological factor of morbimortality in cervical cancer. Several factors have been associated with the development of cervical disease, but viral load has recently been proposed as an indicator of cervical neoplasia. Therefore, a single measurement of viral load could be a suitable biomarker. We examined HPV viral load as a prognostic biomarker of cervical neoplasia. We used cervical scrapes to determine the total HPV viral load of 46 Mexican patients with various stages of cervical intraepithelial neoplasia (CIN) using hybrid capture assay coupled with a quantitative polymerase chain reaction method for cellularity estimation. Viral load values of CIN2 and CIN3 samples were compared with samples without cervical pathology (WP); all values of viral load were normalized by number of cells analyzed. The analysis showed significant differences in viral load between CIN2 and WP samples (P = 0.01) and between CIN3 and WP samples (P = 0.02). By contrast, no significant difference was detected between viral loads in CIN2 and CIN3 samples. The results showed significant difference between viral loads in CIN2 and CIN3 samples and that in WP samples. HPV viral load was significantly different between patients with CIN2-CIN3 and those with WP and can be used as a predictor of lesions.

A hybrid-capture assay to detect HPV mRNA ratios in cervical specimens

Human papillomavirus (HPV) DNA screening benefits cervical cancer diagnosis, but a few HPV infections result in cancer. Assays that predict cancer are desirable. A potential biomarker is the ratio of HPV E6-7 over E2 transcripts, which may increase during early cancer progression. Modified hybrid-capture technology detected, in separate wells, HPV E6-7 or E2 mRNA of HPV 16 or HPV 18 in samples. The limit of detection was approximately 1000 copies of in vitro transcribed RNA with linear dynamic range approximately four logs. No cross-reactivity between HPV 16 and HPV 18 mRNAs was detected. RNA of SiHa cells was stable in clinical specimen pools for 67 days, as determined by RT-PCR. The ratio of HPV E6-7:E2 mRNAs was relatively high for cancer cells lines, SiHa, Caski and HeLa cells preserved in clinical specimen pools. A broad distribution of HPV 16 E6-7:E2 mRNA ratio was detected in a small set of clinical specimens with various histological diagnoses. Some specimen ratios were so high for cancer cell lines, but the significance of the results needs to be determined. This method may help determine the pattern of gene expression in HPV-related disease or in other systems.

Use of HC2 to triage women with borderline and mild dyskaryosis in the UK

To investigate the feasibility and efficiency of a nationwide rollout of human papillomavirus (HPV)-based triage for cervical cytology results of borderline (BD) or mild dyskaryosis (MD) in the UK, a study at six sentinel sites including more than 10 000 women aged 25–64 was conducted in a real life setting (Kelly et al, 2011). The applied triage test was the Hybrid Capture-2 assay (HC2, Qiagen, GmbH, Hilden, Germany), which detects DNA of 13 high-risk (hr) HPV types. The cut-off chosen for a positive HPV test was ⩾2 RLU/PC (relative light units/positive control), which is lower than what was used in a previous pilot study (⩾3 RLU/PC), but higher than what is widely used in Europe and the US (⩾1 RLU/PC). All HPV-positive women were referred for colposcopy involving biopsies from visually abnormal areas of the cervical epithelium. HPV-negative women and HPV-positive women with negative colposcopy or histology findings were returned to the usual screening schedule. A histological result of CIN1 (cervical intraepithelial neoplasia of grade 1) resulted in a follow-up cytology 12 months later, whereas CIN2 or worse lesions (CIN2+) were treated. Outcomes were the referral rate to colposcopy (or rate of HPV-positivity) and the yield of underlying CIN2+ or CIN3+ among referred women (positive predictive value (PPV)). To evaluate the heterogeneity of HPV prevalence and PPV for cervical disease, several covariates were addressed, including age of the woman, type of liquid-cytology (SurePath (BD, TriPath Imaging inc., Burlington, NC, USA) or ThinPrep (Hologic Inc., Marlborough, MA, USA)) and laboratory site. Below, we summarize the results of the six sentinel studies and include them into previously published meta-analyses on the same topic (Arbyn et al, 2005; Arbyn et al, 2006; Arbyn et al, 2009).

Newly developed liquid-based cytology. TACAS™: cytological appearance and HPV testing using liquid-based sample

Cell profiles determined by the thin-layer advanced cytology assay system (TACAS™), a liquid-based cytology technique newly developed in Japan, were analyzed in this study. Hybrid capture 2 (HC-2) was also performed using the liquid-based samples prepared by TACAS to ascertain its ability to detect human papillomavirus (HPV). Cell collection samples from uterine cervix were obtained from 359 patients and examined cytologically. A HC-2 assay for HPV was carried out in the cell specimens. All specimens were found to show background factors such as leukocytes. After excluding the 5 unsatisfactory cases from the total 354 cases, 82 cases (23.2%) were positive and 272 cases (76.8%) were negative for HPV. Cell specimens from 30 HPV-positive cases and 166 HPV-negative cases were subjected to 4weeks of preservation at room temperature. Then, when subsequently re-assayed, 28 cases (93.3%) in the former group were found to be HPV positive and 164 cases (98.8%) in the latter group were found to be HPV negative. These results supported the excellent reproducibility of TACAS for HPV testing. A reasonable inference from the foregoing analysis is that TACAS may be distinguished from other liquid-based cytological approaches, such as ThinPrep and SurePath, in that it can retain the cell backgrounds. Furthermore, this study raises the possibility that cell specimens prepared using TACAS could be preserved for at least 4weeks prior to carrying out a HC-2 assay for HPV.