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Analytical evaluation of the PapilloCheck test, a new commercial DNA chip for detection and genotyping of human papillomavirus.

International audienceRecently, a commercially available HPV DNA chip, the PapilloCheck test, developed by Greiner Bio-One, has become available for human papillomavirus (HPV) genotyping. The PapilloCheck test is a PCR-based test using a new consensus primer set targeting the E1 HPV gene. HPV oligoprobes immobilized on a DNA chip allow for the identification of 24 HPV types from the amplified product. In the present study, the analytical performance of the PapilloCheck test is compared to the Linear Array HPV genotyping test (Roche Diagnostics). Cervical specimens collected in PreservCyt (Cytyc) solution and obtained from women who presented abnormal cytological findings were tested primarily by the Hybrid Capture 2 High-Risk assay (HC2-HR, QIAGEN). A total of 144 samples were selected according to the signal intensity obtained with the HC2-HR test, expressed as RLU/CO value, and divided into 4 groups as follows: [0-1] RLU/CO (negative HC2-HR result, 34 samples); [1-5] RLU/CO (positive HC2-HR result, 30 samples); [5-40] RLU/CO (positive HC2-HR result, 40 samples); >40 RLU/CO (positive HC2-HR result, 40 samples). The concordance levels between the HC2-HR test and each of the genotyping assays was similar (88.8%) and the crude agreement between these assays was considered as "good". The detailed analysis of the discrepant results confirmed a possibly high rate of false positive results of HC2-HR test in the 1-5 RLU/CO grey zone. Genotype-specific comparison analysis was limited to the 23 HPV types detected by both genotyping assays (HPV types 6, 11, 16, 18, 31, 33, 35, 39, 40, 42, 45, 51, 52, 53, 55, 56, 58, 59, 66, 68, 70, 73 and 82). Of the 135 samples available for comparison, 91 (67.4%) showed absolute agreement between the assays (concordant genotype-specific results), 34 (25.1%) showed correspondence for some but not all genotypes detected by both assays (compatible genotype-specific results), and the remaining 10 (7.4%) samples did not show any similarity between the tests (discordant results). The majority of discordances were found in samples containing multiple HPV types and in samples harboring low amounts of HPV. For some HPV genotypes, there were slight differences in the detection rate between the two genotyping methods. The Linear Array test seemed to be more sensitive to detect HPV type 53 whereas PapilloCheck test seemed to be more sensitive to detect HPV type 56. For the other genotypes, including HPV types 16 and 18, the results obtained by the two methods did not differ significantly. In conclusion, this study shows that the PapilloCheck test and the Linear Array test give comparable results for detecting HPV in cervical specimens. However, these results also suggest that there is a need to standardize the type-specific sensitivity of genotyping methods and to evaluate their accuracy to detect multiple HPV infections. This would be a prerequisite for the use of genotyping assays in cervical cancer screening algorithms

PreservCyt Transport Medium Used for the ThinPrep Pap Test Is a Suitable Medium for Detection of Chlamydia trachomatis by the COBAS Amplicor CT/NG Test: Results of a Preliminary Study and Future Implications

The commercial COBAS Amplicor CT/NG test (Roche Diagnostic Systems, Meylan, France) is a sensitive and specific method for detection of Chlamydia trachomatis infections. This test currently consists of using a nucleic acid amplification method to detect C. trachomatis in first-void urine specimens and in endocervical swabs collected in 2-sucrose-phosphate (2SP) transport medium. We conducted a prospective study to determine whether the automated COBAS Amplicor CT/NG test can detect C. trachomatis in cervical specimens collected in PreservCyt transport medium (ThinPrep Pap Test; Cytyc Corporation, Boxborough, Mass.). PreservCyt medium is used to preserve cervical samples before the preparation of ThinPrep slides. We collected 1,000 cervical specimens from young women (age range, 15 to 25 years) during routine Pap smear tests. Only specimens with normal cytology and in which the gynecologist found no clinical evidence of urogenital infections were selected. The samples were stored in PreservCyt transport medium at 15 to 20°C. C. trachomatis was detected in 22 of the 1,000 cervical specimens that had been stored in PreservCyt. To confirm the positive samples, the test was repeated on new endocervical swab specimens collected in 2SP transport medium. Only 9 of the 22 positive patients agreed to undergo this control, but all 9 retested positive. To evaluate the influence of storage conditions on the sensitivity of the C. trachomatis PCR test, all of the positive samples were stored at 15 to 20°C in PreservCyt transport medium and were retested every 2 weeks for 6 weeks. C. trachomatis was successfully amplified from all 22 specimens for the whole 6-week period. The prevalence of C. trachomatis infection was 2.2% in our study population. These results demonstrate that PreservCyt transport medium is a suitable transport medium for detection of C. trachomatis by the COBAS Amplicor CT/NG test. The ThinPrep Pap Test may enable gynecologists to monitor for both cervical lesions and C. trachomatis infections with a single endocervical specimen

Human papillomavirus genotype distribution in low-grade squamous intraepithelial lesions in France and comparison with CIN2/3 and invasive cervical cancer: the EDiTH III study.

International audienceOBJECTIVES: In the present study (EDiTH III study), the genotype-specific prevalence of HPV in low-grade squamous intraepithelial lesions (LSIL) was estimated to predict the potential benefit of HPV vaccination in France. This prevalence was compared to that previously reported in France in high-grade cervical intraepithelial neoplasia (CIN2/3, EDiTH II study) and squamous cell carcinoma (SCC, EDiTH I study) to identify the genotypes preferentially associated with a progression to malignancy. METHODS: 397 smears with LSIL diagnosis (Preservcyt) were retrospectively collected in different centres in France and genotyped using the INNO-LiPA assay allowing the detection of 24 HPV genotypes. RESULTS: HPV was found in 98% of cases. The most prevalent genotypes in LSIL in France were HPV 66 (25%), HPV 16 (21%), HPV 53 (18%), 51 (17%) and 52 (14%). HPV 16 and/or 18 were present in 28% and HPV 6, 11, 16 and/or 18 in 33% of LSIL. The highest SCC/LSIL prevalence ratios were shown for HPV 16, 33 and 18. CONCLUSIONS: With a 95% vaccine efficacy on CIN1 and theoretical vaccine coverage of 100%, HPV vaccination might prevent 27% (with a 16, 18 bivalent vaccine) and up to 32% (with a 6, 11, 16, 18 quadrivalent vaccine) of LSIL cases in France. In this study, LSIL related to HPV 16, 18 or 33 are at highest risk of progression to malignancy and thus could require a stringent surveillance. Conversely, anxiety and over-treatment could be avoided in women with low risk of progression

Human papillomavirus genotype distribution in anal cancer in France: The EDiTH V study.

International audienceAnal cancer is a rare cancer but its incidence is increasing. Human papillomavirus (HPV) infection seems to be associated with the occurrence of most cases. The genotype-specific prevalence of HPV in anal cancer was estimated to assess the potential benefit of HPV vaccination in France. Anal cancer histological specimens were retrospectively recruited in 2008 from 16 French centres and centrally tested for HPV genotyping using the INNO-LiPA assay allowing the detection of 28 genotypes. Results were analyzed according to age, gender, HIV status when available and histological diagnosis. A total of 366 anal cancer cases were analyzed among which 62% were females. Mean age at diagnosis was 54.8 years in males and 66.4 years in females (p < 0.001). HPV was found in 96.7% of cases, 72% being infected by a single HPV type. Presence of at least one high-risk genotype was observed in 91% of cases (96% in females and 83% in males; p < 0.001). HPV16 was by far the most prevalent genotype (75%), followed by HPV18, HPV52, HPV33, and HPV51 (4-6%). HPV16/18 alone or in association were found in 78% of all cases. HIV-positive cases had a higher proportion of multiple HPV infection than HIV-negative cases and a slightly different HPV type distribution with an under-representation of HPV16 and an over-representation of other types. Our results indicate that anal cancer rarely occurs in the absence of HPV and emphasize the predominant role of HPV16. The potential benefit of HPV vaccine on the occurrence of anal cancer should be further evaluated