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1.
Papillomavirus Res ; 6: 1-5, 2018 12.
Article in English | MEDLINE | ID: mdl-29842928

ABSTRACT

Commercial assays measuring HPV E6 viral oncoproteins, E6/E7 mRNA or DNA were used to test neck lymph node fine needle aspirates (FNA) and oropharyngeal samples (saliva and oral swabs) from 59 Canadian patients with oropharyngeal squamous cell carcinomas (OPSCC). Overall agreements of p16 antigen staining of tumors to FNA tested for OncoE6™, Aptima HPV E6/E7 mRNA and cobas HPV DNA were 81.4% (k 0.53), 94.9% (k 0.83) and 91.1% (k 0.73) respectively. Using HPV presence in a subset of 25 tumors as the comparator, overall agreement was 64.0% (k 0.08) with OncoE6™, 88.0% (k 0.65) with Aptima HPV E6/E7 mRNA and 91.7% (k 0.70) with cobas HPV DNA. HPV testing of oropharyngeal samples yielded lower agreements with tumor markers; 23.7-24.0% (k 0.02), 55.9-68.0% (k 0.24-0.37) and 78.9-86.9% (k 0.49-0.58) in the 3 respective tests. HPV 16 was present in 93.7-100% of the samples tested and showed 100% genotype agreement between FNA and tumors. The high rates for HPV E6 oncoproteins and E6/E7 mRNA suggests most patients were experiencing transcriptionally active HPV-related OPSCC. Results from these commercial assays performed on FNA but not oropharyngeal samples showed moderate to very good agreements with p16 and HPV testing of tumors.


Subject(s)
Biomarkers, Tumor/analysis , Biopsy, Fine-Needle , Carcinoma, Squamous Cell/pathology , Lymph Nodes/pathology , Oncogene Proteins/analysis , Oncogene Proteins/genetics , Oropharyngeal Neoplasms/pathology , Adult , Aged , Canada , Female , Humans , Male , Middle Aged
2.
J Clin Microbiol ; 50(4): 1281-4, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22259215

ABSTRACT

Chlamydia trachomatis and Neisseria gonorrhoeae are common causes of sexually transmitted infections, and there is interest in screening SurePath liquid-based Pap (L-Pap) samples with Aptima Combo 2 (AC2), Amplicor (AMP), and ProbeTec ET (PT) assays. SurePath L-Pap samples and a cervical swab (CS) were collected from 394 women attending health clinics in Hamilton and Toronto, ON, Canada. L-Pap samples were tested with the three assays prior to being processed for cytology, and the CS sample was tested with AC2. The prevalence of C. trachomatis was 8.9%, and that of N. gonorrhoeae was 1.5%. By using the positives from CS testing, as well as CS negatives corresponding to L-Pap samples that tested positive in 2 of 3 assays, the sensitivities of AC2, AMP, and PT for C. trachomatis in precytology samples were calculated to be 97.1% (34 of 35 positive samples were detected), 91.4% (32 of 35 were detected), and 77.1% (27 of 35 were detected), respectively. Six women were infected with N. gonorrhoeae. After cytology processing, the results of testing the remaining liquid in the L-Pap vial and the cell-enriched fraction for C. trachomatis by AC2 showed positive agreements of 98.9% (kappa [k], 0.93) and 98.7% (k, 0.92), respectively, with the results of testing precytology L-Pap samples. Although all testing showed high specificity, testing for C. trachomatis by AC2 was significantly more sensitive than testing by PT for SurePath samples (P = 0.02). Newer versions of AMP (Cobas 4800) and PT (Q(x) with XTR technology) need published evaluations for detecting C. trachomatis and N. gonorrhoeae in L-Pap samples. C. trachomatis testing can be performed with similar results on pre- and postcytology SurePath samples.


Subject(s)
Chlamydia Infections/diagnosis , Chlamydia trachomatis/genetics , Gonorrhea/diagnosis , Molecular Diagnostic Techniques , Neisseria gonorrhoeae/genetics , Nucleic Acid Amplification Techniques , Adolescent , Adult , Aged , Cervix Uteri/microbiology , Chlamydia Infections/epidemiology , Female , Gonorrhea/epidemiology , Humans , Middle Aged , Prevalence , Sensitivity and Specificity , Young Adult
3.
J Oncol ; 2012: 503432, 2012.
Article in English | MEDLINE | ID: mdl-22174716

ABSTRACT

Background. Liquid-based Pap (L-Pap) media are used for Pap and human papillomavirus (HPV) testing. Objectives. To compare RealTime High Risk (HR) HPV testing of a new collection kit (Cervi-Collect) and PreservCyt L-Pap specimens. To determine ease of use and safety of Cervi-Collect. Methods. L-Pap samples (n = 203) were tested with HC2 and RealTime HR HPV and Cervi-Collect with RealTime HR HPV. Discordant samples were genotyped. Results. L-Pap and Cervi-Collect specimens tested by RealTime HR HPV showed 93.1% agreement (Kappa 0.86). RealTime HR HPV and HC2 on L-Pap had 90.3% agreement (Kappa 0.80). RealTime HR HPV on Cervi-Collect and HC2 on L-Pap showed 88.2% agreement (Kappa 0.76). Sixteen of 21 samples which were HC2 negative and RealTime HR HPV positive on L-Pap or Cervi-Collect contained HR HPV genotypes. Eleven healthcare collectors were in strong agreement on a usability and safety questionnaire. Conclusion. Cervi-Collect samples were easy to collect and showed strong agreement with L-Pap samples tested with RealTime HR HPV or HC2.

4.
J Virol Methods ; 162(1-2): 291-3, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19703493

ABSTRACT

A dual collection device containing flocked and wrapped rayon swabs was used to collect vaginal and cervical samples from 494 women. The swabs were separated into individual tubes and sent to the laboratory in a dry state, where they were hydrated and tested for high risk HPV DNA [Digene-Qiagen hybrid capture 2] and Chlamydia trachomatis using in-house real-time PCR. The flocked swabs identified more high risk HPV and C. trachomatis infections from both sampling sites.


Subject(s)
Cervix Uteri , Chlamydia trachomatis/isolation & purification , Papillomaviridae/isolation & purification , Specimen Handling , Vagina , Cellulose , Cervix Uteri/microbiology , Cervix Uteri/virology , Chlamydia Infections/microbiology , Chlamydia trachomatis/genetics , DNA, Bacterial/analysis , DNA, Viral/analysis , Female , Humans , Papillomaviridae/genetics , Papillomavirus Infections/virology , Polymerase Chain Reaction/methods , Risk , Specimen Handling/instrumentation , Specimen Handling/methods , Uterine Cervical Neoplasms/virology , Vagina/microbiology , Vagina/virology , Vaginal Smears , Uterine Cervical Dysplasia/virology
5.
J Clin Microbiol ; 45(8): 2355-8, 2007 Aug.
Article in English | MEDLINE | ID: mdl-17537943

ABSTRACT

Infections with Chlamydia trachomatis and Neisseria gonorrhoeae are often asymptomatic. Liquid-based Pap (L-Pap) screening may provide samples for testing by commercial assays. Women attending a health clinic or a street youth clinic had a PreservCyt ThinPrep sample and a cervical swab (CS) collected. The L-Pap sample was tested for cytopathology; then 1 ml was transferred to an L-Pap specimen transfer tube for testing by the Gen-Probe APTIMA assays (APTIMA Combo 2 [AC2], APTIMA C. trachomatis [ACT], and APTIMA N. gonorrhoeae [AGC]). The residual L-Pap sample was tested for C. trachomatis and N. gonorrhoeae using Roche AMPLICOR (AMP) and Becton Dickinson ProbeTec (PT). The CS was tested by AC2. A patient was considered infected if two specimens were positive or if a single specimen was positive in two tests. The prevalence of infection was 10% (29/290) for C. trachomatis and 2.4% (7/290) for N. gonorrhoeae. Most of the positive patients had specimens that were reactive in all assays (20/29 for C. trachomatis; 6/7 for N. gonorrhoeae). Four patients had double infections. The sensitivities and specificities of the various tests for the specimens tested were as follows. For C. trachomatis on L-Pap, sensitivity and specificity were 100 and 98.1%, respectively, for ACT, 93.1 and 98.8% for AC2, 86.2 and 91.2% for AMP, and 72.4 and 92.7% for PT. For N. gonorrhoeae on L-Pap, sensitivity and specificity were 100% for both AGC and AC2, 85.7 and 100% for AMP, and 85.7 and 100% for PT. For AC2 with CSs, sensitivity and specificity were 93.1 and 98.5%, respectively, for C. trachomatis, and both were 100% for N. gonorrhoeae. There were significant differences in sensitivity and specificity (P < 0.001). The APTIMA assays were more sensitive and specific than AMP or PT for detecting women's C. trachomatis and/or N. gonorrhoeae infections by testing ThinPrep samples.


Subject(s)
Chlamydia trachomatis/isolation & purification , Molecular Diagnostic Techniques , Neisseria gonorrhoeae/isolation & purification , Vaginal Smears , Chlamydia Infections/microbiology , Chlamydia trachomatis/genetics , Female , Gonorrhea/microbiology , Humans , Neisseria gonorrhoeae/genetics , Reagent Kits, Diagnostic , Sensitivity and Specificity
6.
J Clin Microbiol ; 45(3): 747-51, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17202273

ABSTRACT

We evaluated a new real-time PCR-based prototype assay for the detection of Chlamydia trachomatis and Neisseria gonorrhoeae developed by Abbott Molecular Inc. This assay is designed to be performed on an Abbott m2000 real-time instrument system, which consists of an m2000sp instrument for sample preparation and an m2000rt instrument for real-time PCR amplification and detection. The limit of detection of this prototype assay was determined to be 20 copies of target DNA for both C. trachomatis and N. gonorrhoeae, using serially diluted linearized plasmids. No cross-reactivity could be detected when 55 nongonococcal Neisseria isolates and 3 non-C. trachomatis Chlamydia isolates were tested at 1 million genome equivalents per reaction. Concordance with the Roche Amplicor, BDProbeTec ET, and Gen-Probe APTIMA Combo 2 tests was assessed using unlinked/deidentified surplus clinical specimens previously analyzed with these tests. For C. trachomatis, concordance for positive results ranged from 93.7% to 100%, while concordance for negative results ranged from 98.2% to 100%. For N. gonorrhoeae, concordance for positive and negative results ranged from 91.4% to 100% and 99.3% to 100%, respectively. A workflow analysis of the prototype assay was conducted to obtain information on throughput under laboratory conditions. At 48 samples/run, the time to first result for both C. trachomatis and N. gonorrhoeae was 4.5 h. A total of 135 patient specimens could be analyzed in 8.9 h, with 75 min of hands-on time. This study demonstrated the technical and clinical feasibility of the new Abbott real-time PCR C. trachomatis/N. gonorrhoeae assay.


Subject(s)
Chlamydia Infections/diagnosis , Chlamydia trachomatis/isolation & purification , Gonorrhea/diagnosis , Neisseria gonorrhoeae/isolation & purification , Polymerase Chain Reaction , Reagent Kits, Diagnostic , Automation , Chlamydia Infections/microbiology , Chlamydia trachomatis/genetics , Female , Female Urogenital Diseases/diagnosis , Female Urogenital Diseases/microbiology , Gonorrhea/microbiology , Humans , Magnetics , Male , Male Urogenital Diseases/diagnosis , Male Urogenital Diseases/microbiology , Neisseria gonorrhoeae/genetics , Polymerase Chain Reaction/instrumentation , Polymerase Chain Reaction/methods , Sensitivity and Specificity , Specimen Handling/methods
7.
J Clin Microbiol ; 44(8): 2681-8, 2006 Aug.
Article in English | MEDLINE | ID: mdl-16891478

ABSTRACT

The emergence of a novel coronavirus (CoV) as the cause of severe acute respiratory syndrome (SARS) catalyzed the development of rapid diagnostic tests. Stool samples have been shown to be appropriate for diagnostic testing for SARS CoV, although it has been recognized to be a heterogeneous and difficult sample that contains amplification inhibitors. Limited information on the efficiency of extraction methods for the purification and concentration of SARS CoV RNA from stool samples is available. Our study objectives were to determine the optimal extraction method for SARS CoV RNA detection and to examine the effect of increased specimen volume for the detection of SARS CoV RNA in stool specimens. We conducted a multicenter evaluation of four automated and four manual extraction methods using dilutions of viral lysate in replicate mock stool samples, followed by quantitation of SARS CoV RNA using real-time reverse transcriptase PCR. The sensitivities of the manual methods ranged from 50% to 100%, with the Cortex Biochem Magazorb method, a magnetic bead isolation method, allowing detection of all 12 positive samples. The sensitivities of the automated methods ranged from 75% to 100%. The bioMérieux NucliSens automated extractor and miniMag extraction methods each had a sensitivity of 100%. Examination of the copy numbers detected and the generation of 10-fold dilutions of the extracted material indicated that a number of extraction methods retained inhibitory substances that prevented optimal amplification. Increasing the volume of sample input did improve detection. This information could be useful for the extraction of other RNA viruses from stool samples and demonstrates the need to evaluate extraction methods for different specimen types.


Subject(s)
Feces/virology , Molecular Diagnostic Techniques , RNA, Viral/analysis , Severe Acute Respiratory Syndrome/diagnosis , Severe acute respiratory syndrome-related coronavirus/isolation & purification , Humans , RNA, Viral/genetics , RNA, Viral/isolation & purification , Reverse Transcriptase Polymerase Chain Reaction , Severe acute respiratory syndrome-related coronavirus/genetics , Sensitivity and Specificity , Severe Acute Respiratory Syndrome/virology
8.
J Clin Microbiol ; 43(3): 1372-3, 2005 Mar.
Article in English | MEDLINE | ID: mdl-15750110

ABSTRACT

The Centers for Disease Control and Prevention recommended confirming positive screening tests for Chlamydia trachomatis when positive predictive values are <90%. It is accepted that less sensitive tests (i.e., culture and immunoassays) should not be used to confirm the results of more sensitive nucleic acid amplification tests (NAATs). We show that the same principle applies when NAATs are used for confirmation.


Subject(s)
Chlamydia trachomatis/isolation & purification , Nucleic Acid Amplification Techniques , Centers for Disease Control and Prevention, U.S. , Chlamydia trachomatis/genetics , Female , Humans , Male , Sensitivity and Specificity , United States
9.
J Clin Microbiol ; 43(1): 127-31, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15634960

ABSTRACT

A clinical evaluation was conducted in six North American centers to determine the ability of APTIMA CT (ACT) and APTIMA GC (AGC) nucleic acid amplification assays to detect Chlamydia trachomatis and Neisseria gonorrhoeae infections in 1,322 men by testing their urethral swabs and first-catch urine (FCU). The results obtained with ACT and AGC assays were compared to an infected patient status determined by testing the specimens with the APTIMA Combo 2 and the BD ProbeTec energy transfer multiplex assays. Symptoms did not influence the values. Positive and negative agreements of the ACT and AGC assays for individual specimens were high, with each comparator assay ranging between 94.3 and 100% for positives and 93.9 and 99.4% for negatives. The ACT and AGC assays performed on noninvasive specimens such as FCU effectively identified C. trachomatis or N. gonorrhoeae infections in symptomatic and asymptomatic men and should be suitable for screening male populations.


Subject(s)
Chlamydia trachomatis/isolation & purification , Neisseria gonorrhoeae/isolation & purification , Nucleic Acid Amplification Techniques/methods , Specimen Handling/methods , Urethra/microbiology , Urine/microbiology , Adolescent , Adult , Aged , Chlamydia Infections/microbiology , Gonorrhea/microbiology , Humans , Male , Middle Aged , Predictive Value of Tests , Sensitivity and Specificity
10.
Sex Transm Infect ; 79(3): 237-9, 2003 Jun.
Article in English | MEDLINE | ID: mdl-12794211

ABSTRACT

We assessed the correlation between ligase chain reaction (LCR) on first void urine (FVU) and cultures of urethral and cervical swabs to detect chlamydia during three post-treatment follow up visits for 10 men and 19 women with genital chlamydial infections who had been treated with azithromycin or doxcycline.


Subject(s)
Chlamydia Infections/diagnosis , Ligase Chain Reaction/standards , Adult , Anti-Bacterial Agents/therapeutic use , Azithromycin/therapeutic use , Bacteriuria/diagnosis , Bacteriuria/urine , Chlamydia Infections/drug therapy , Chlamydia Infections/urine , Doxycycline/therapeutic use , Female , Follow-Up Studies , Humans , Ligase Chain Reaction/methods , Male , Reagent Kits, Diagnostic/standards , Recurrence , Sensitivity and Specificity , Specimen Handling
11.
Sex Transm Dis ; 30(4): 345-7, 2003 Apr.
Article in English | MEDLINE | ID: mdl-12671557

ABSTRACT

BACKGROUND: Noninvasive urine samples have been used to diagnose Chlamydia trachomatis infections, with the assumption that the first-void urine (FVU), defined as the first 20 to 30 ml at any micturition, would be the optimal collection. We compared testing technologies on first, second, and third volumes for diagnosis. GOAL: The goal was to test in nonculture assays three sequential volumes of urine from men also undergoing urethral swabbing for C trachomatis culture specimens. STUDY DESIGN: A total of 237 men attending an STD clinic (C trachomatis prevalence, 11%) collected three containers of urine (each containing 20-30 mL) for testing in four nonculture assays. A urethral swab specimen was tested in cell culture. RESULTS: The numbers of men positive by testing of FVU with nucleic acid amplification (LCx chlamydia), nucleic acid hybridization (PACE 2), enzyme immunoassay (Chlamydiazyme), and a leukocyte esterase dipstick were 26, 7, 14, and 11, respectively; urethral culture identified 6 of the infected men. Comparative testing of all voids from the 26 men positive by the FVU assays demonstrated a reduction of LCx-positives. Non-amplified-test positivity declined precipitously in subsequent voids, approaching zero in the third void. The presence of symptoms and time of last void up to 8 hours had little effect on the number of positives detected by LCx of FVU. CONCLUSION: Amplified testing of FVU was most effective for diagnosing infection in these men.


Subject(s)
Chlamydia Infections/diagnosis , Chlamydia Infections/epidemiology , Chlamydia trachomatis/isolation & purification , Urethritis/diagnosis , Urethritis/epidemiology , Urinalysis/standards , Adult , Bacteriuria/microbiology , Chlamydia Infections/microbiology , Chlamydia Infections/urine , Humans , Male , Mass Screening/methods , Mass Screening/standards , Ontario/epidemiology , Prevalence , Urethra/microbiology , Urethritis/microbiology , Urethritis/urine , Urinalysis/methods
12.
J Clin Microbiol ; 41(2): 778-82, 2003 Feb.
Article in English | MEDLINE | ID: mdl-12574282

ABSTRACT

Inhibitors in clinical specimens can be detected by adding the target of nucleic acid amplification to the sample. Introduction of a Chlamydia trachomatis L2 434 preparation containing 12 elementary bodies (EBs) into first-void urine (FVU) from 225 nonpregnant women and 190 pregnant women before specimen processing by the assays produced false-negative rates of 0.48% (2 of 415 specimens) and 13% (44 of 338 specimens) by the APTIMA Combo 2 and the Chlamydia LCx tests, respectively. Reducing the amount of C. trachomatis added to one EB, a concentration closer to the APTIMA Combo 2 test cutoff, for a subset of 244 FVU specimens increased the number of specimens with false-negative results by the APTIMA Combo 2 assay to 7 (2.9%), suggesting that the strength of the input C. trachomatis per specimen has an influence on the number of specimens with false-negative results. Repeat testing after overnight storage and dilution decreased the APTIMA Combo 2 test false-negative rates to 0% (0 of 415 specimens) with the stronger inoculum and 0.8% (2 of 244 specimens) with the weaker inoculum; the false-negative rate of the LCx assay was reduced to 5.4% (18 of 334 specimens). When an additional 70 FVU specimens from women to which 12 EBs were added before specimen processing were tested by the LCx assay, 34 specimens had false-negative results, whereas 21 specimens had false-negative results when the C. trachomatis EBs were introduced after processing. Nine of the 21 specimens to which EBs were added after processing and all of the 34 urine specimens to which the target was added before processing remained falsely negative on repeat testing at a 1:2 dilution, suggesting that input C. trachomatis DNA was lost during processing by the LCx assay. In contrast, the APTIMA Combo 2 assay appears to have a higher sensitivity and either lost little nucleic acid during processing or demonstrated few problems with inhibitors of transcription-mediated amplification.


Subject(s)
Chlamydia trachomatis/isolation & purification , False Negative Reactions , Reagent Kits, Diagnostic , Urine/microbiology , Adult , Bacteriological Techniques , Female , Humans , Pregnancy
13.
Sex Transm Infect ; 78(4): 232-4, 2002 Aug.
Article in English | MEDLINE | ID: mdl-12181457

ABSTRACT

Nucleic acid amplification (NAA) assays for the diagnosis of Chlamydia trachomatis infections started to appear in the peer reviewed literature about 12 years ago and during that period we have seen an incredible effort put into the development and evaluation of commercially developed NAA kits to diagnose and treat infections.


Subject(s)
Chlamydia Infections/diagnosis , Chlamydia trachomatis , Reagent Kits, Diagnostic , Humans , Nucleic Acid Amplification Techniques
14.
J Clin Microbiol ; 40(7): 2632-4, 2002 Jul.
Article in English | MEDLINE | ID: mdl-12089293

ABSTRACT

Nucleic acid amplification assays such as the ligase chain reaction and PCR have encountered reproducibility problems. The initial extract and a newly extracted aliquot of urine specimens (n = 120) which had signal-to-cutoff (S/CO) ratios above 0.80 by the LCx Chlamydia assay were retested. Nucleic acid was extracted from an additional urine sample for testing by the AMPLICOR PCR Chlamydia assay. Fifteen percent (18 of 120) of the urine specimens were negative by all repeat tests (initial mean S/CO ratio by the LCx Chlamydia assay, 0.93; S/CO ratio range, 0.80 to 3.30). Repeat testing of the 102 specimens with possible positive results by the LCx Chlamydia assay by use of the initially extracted aliquot confirmed the results for 95 (93.1%) of the specimens; repeat testing of a newly extracted aliquot confirmed the results for 87 (85.3%) of the specimens. Twenty specimens had discordant results by the two repeat LCx Chlamydia assays. A total of 78 of 102 (76.5%) of the specimens were positive by the AMPLICOR PCR, and the AMPLICOR PCR confirmed the results for 82.1% (78 of 95) and 89.6% (78 of 87) of the specimens positive by the two repeat LCx Chlamydia assays, respectively. Some of the discrepancies observed by multiple repeat tests may have been due to specimen mislabeling or contamination during performance of the procedure rather than to the LCx Chlamydia assay. Both assays suffered from a lack of reproducibility on repeat testing with a small proportion of specimens, probably due to the presence of low levels of DNA, the presence of variable amounts of amplification inhibitors, and the loss of DNA during extraction.


Subject(s)
Chlamydia Infections/diagnosis , Chlamydia trachomatis/genetics , Chlamydia trachomatis/isolation & purification , Ligase Chain Reaction/methods , Polymerase Chain Reaction/methods , Urine/microbiology , Algorithms , Chlamydia Infections/microbiology , DNA, Bacterial/genetics , DNA, Bacterial/urine , Female , Humans , Ligase Chain Reaction/statistics & numerical data , Male , Polymerase Chain Reaction/statistics & numerical data , Reproducibility of Results , Urinary Tract Infections/diagnosis , Urinary Tract Infections/microbiology
15.
Sex Transm Dis ; 28(12): 701-9, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11725225

ABSTRACT

BACKGROUND: Undetected and untreated Chlamydia trachomatis infections can result in a significant health burden. Diagnostic testing refers to tests performed on patients with symptoms, whereas screening refers to testing specimens in asymptomatic patients. The goal of diagnostic testing and screening programs are early identification of infections to prevent upper tract infection and transmission to other partners. GOAL: To compare the costs and outcomes of alternative diagnostic testing and screening programs for women ages 15 to 24 years in the province of Ontario, Canada. STUDY DESIGN: Using outcome probabilities from the literature and a consensus group, together with the costs from insurance billing, a decision analytic model was constructed to determine the baseline risk of C trachomatis and related sequelae. Seven diagnostic testing and screening programs were compared over a 10-year period. The programs compared included the use of nucleic acid amplification assays collected from urine or endocervical swab specimens. RESULTS: Largely because of lower sensitivity the urine-based testing or screening programs were dominated by the swab-based programs. The move from swab-based testing to a swab-based screening program for high-risk women costs $1873 per case of C trachomatis averted. Expanding the program further to include all women in Ontario between 15 and 24 years of age is considerably more costly at $5990 per case averted. CONCLUSIONS: It is more costly and more effective to screen and treat high-risk women ages 15 to 24 years for C trachomatis than to perform only swab-based diagnostic testing on symptomatic women. Expanding the screening program to include all women ages 15 to 24 years is considerably more expensive and only moderately more effective than screening only high-risk women.


Subject(s)
Chlamydia Infections/prevention & control , Chlamydia trachomatis/isolation & purification , Mass Screening/economics , Mass Screening/standards , Pelvic Inflammatory Disease/prevention & control , Adolescent , Adult , Chlamydia Infections/microbiology , Chlamydia Infections/urine , Cost-Benefit Analysis , Decision Trees , Female , Humans , Ontario , Pelvic Inflammatory Disease/microbiology , Pelvic Inflammatory Disease/urine , Sensitivity and Specificity , Urinalysis/economics , Urinalysis/standards , Vaginal Smears/economics , Vaginal Smears/standards , Women's Health
16.
J Clin Microbiol ; 39(6): 2306-7, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11376077

ABSTRACT

Two endocervical swabs from each of 1,123 women were collected into manufacturer-supplied transport tubes and tested for Chlamydia trachomatis by a polymer conjugate-enhanced (PCE) enzyme immunoassay (EIA) (IDEIA PCE Chlamydia; DAKO) and a ligase chain reaction assay (LCx Chlamydia; Abbott). After confirmation by the EIA blocking test, the sensitivity of the IDEIA PCE remained at 91.8% and the specificity increased from 98.2 to 99.8% compared to LCx.


Subject(s)
Cervix Uteri/microbiology , Chlamydia Infections/diagnosis , Chlamydia trachomatis/isolation & purification , Ligase Chain Reaction/methods , Specimen Handling/methods , Chlamydia Infections/microbiology , Female , Humans , Immunoenzyme Techniques/methods , Reagent Kits, Diagnostic , Sensitivity and Specificity
17.
J Clin Microbiol ; 39(5): 1796-801, 2001 May.
Article in English | MEDLINE | ID: mdl-11325993

ABSTRACT

Nucleic acid amplification of clinical specimens with low target concentration has variable sensitivity. We examined whether testing multiple aliquots of extracted DNA increased the sensitivity and reproducibility of Chlamydia pneumoniae detection by PCR. Nested and non-nested C. pneumoniae PCR assays were compared using 10 replicates of 16 serial dilutions of C. pneumoniae ATCC VR-1310. The proportion positive versus the C. pneumoniae concentration was modeled by probit regression analysis. To validate the model, 10 replicates of 26 previously positive patient specimens of peripheral blood mononuclear cells (PBMC), sputum, or nasopharyngeal swabs (NPS) were tested. The proportion of replicates that were positive varied with the concentration of C. pneumoniae in the sample. At concentrations above 5 infection-forming units (IFU)/ml, both nested and non-nested PCR assay sensitivities were 90% or greater. The nested PCR was more sensitive (median detection, 0.35 versus 0.61 IFU/ml; relative median detection, 0.58; 95% confidence interval, 0.31 to 0.99; P = 0.04). In clinical specimens, replicate PCR detected 15 of 26 (nested) versus 1 of 26 (non-nested, P < 0.001). For PBMC specimens, testing 1, 3, or 5 replicates detected 3, 5, or 9 of 10 positive specimens, respectively. Median C. pneumoniae concentrations were estimated at 0.07 IFU/ml for PBMC and at <0.03 IFU/ml for NPS specimens. We conclude that performing 5 or 10 replicates considerably increased the sensitivity and reproducibility of C. pneumoniae PCR and enabled quantitation for clinical specimens. Due to sampling variability, PCR tests done without replication may miss a large proportion of positive specimens, particularly for specimens with small amounts of target C. pneumoniae DNA present.


Subject(s)
Chlamydophila Infections/microbiology , Chlamydophila pneumoniae/genetics , Chlamydophila pneumoniae/isolation & purification , Polymerase Chain Reaction/methods , DNA, Bacterial/analysis , Humans , Regression Analysis , Reproducibility of Results , Sensitivity and Specificity
19.
Diagn Microbiol Infect Dis ; 41(4): 215-20, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11777663

ABSTRACT

A multiplex PCR (MPCR) for detection of vanA-and vanB-mediated resistance to vancomycin was optimized and adapted for use in the routine microbiology laboratory. Consecutive specimens (1196) submitted for vancomycin resistant Enterococci (VRE) surveillance were processed by clinical technologists on Bile Esculin Azide Agar containing 6 mg/L vancomycin (BEAA/Vanco6) plates and 466 showing black colony growth were processed by conventional biochemical testing (CBT) and by MPCR. CBT identified 208 VRE positives. MPCR detected 205 of the CBT- positives plus an additional 10. Analysis of the discordant specimens determined that 5 CBT- negative/MPCR-positive specimens also contained Enterococci with vanC resistance, 3 CBT-positive/MPCR-negative specimens were true positives, and 5 CBT-negative/MPCR-positive specimens occurred due to technical error. The sensitivity and specificity of MPCR were 98.4% and 96.1%. MPCR identifications of VRE were achieved approximately 48 h earlier than CBT and at 60% of the costs.


Subject(s)
Bacterial Proteins/genetics , Carbon-Oxygen Ligases/genetics , Drug Resistance, Bacterial/genetics , Costs and Cost Analysis , Enterococcus/genetics , Humans , Polymerase Chain Reaction/economics , Polymerase Chain Reaction/methods , Reproducibility of Results , Retrospective Studies
20.
CMAJ ; 163(5): 513-8, 2000 Sep 05.
Article in English | MEDLINE | ID: mdl-11006761

ABSTRACT

BACKGROUND: Certain types of human papillomavirus (HPV) in cervical samples are strongly associated with squamous intraepithelial lesions (SIL) and invasive cervical carcinoma. We determined and compared the test characteristics of testing for HPV with samples obtained by patients and with samples obtained by their physicians. METHODS: In a consecutive series of women referred to a colposcopy clinic at a teaching hospital because of abnormalities on cervical cytologic screening, 200 agreed to collect vulvar, vaginal and urine samples for HPV testing. The physician then collected cervical samples for HPV testing, and colposcopy, with biopsy as indicated, was performed. Presence of HPV was evaluated using the hybrid capture II assay (Digene Corp., Silver Spring, Md.) with a probe cocktail for 13 carcinogenic types. Cervical specimens were also tested for HPV by polymerase chain reaction and hybridization with type-specific probes. Cervical smears for cytologic examination were obtained from all women. RESULTS: High-grade lesions (high-grade squamous intraepithelial lesions [HSIL], equivalent to cervical intraepithelial neoplasia [CIN] grade 2 or 3, and adenocarcinoma) were found in 58 (29.0%) of the 200 women. Carcinogenic types of HPV were detected in the self-collected vaginal samples of 50 (86.2%) of these 58 women, in the self-collected vulvar samples of 36 (62.1%) and in the self-collected urine samples of 26 (44.8%). Carcinogenic types of HPV were detected in the cervical samples collected by physicians for 57 (98.3%) of these 58 women. The remaining 142 women (71.0%) had normal findings or low-grade squamous intraepithelial lesions (LSIL, CIN grade 1). Test results were negative or noncarcinogenic types of HPV were detected in the self-collected vaginal samples of 76 (53.5%) of these 142 women, in the self-collected vulvar samples of 89 (62.7%) and in the self-collected urine samples of 99 (69.7%). The sensitivity for self-collected samples ranged from 44.8% to 86.2%, and the specificity from 53.5% to 69.7%. For the samples collected by physicians, the sensitivity was 98.3% and the specificity 52.1%. The self-sampling methods were generally acceptable to the women: 98.4% of respondents (126/128) deemed urine sampling acceptable, 92.9% (118/127) found vulvar sampling acceptable, and 88.2% (112/127) found vaginal sampling acceptable. INTERPRETATION: Self-collection of samples for HPV testing was acceptable to women attending a colposcopy clinic for investigation of suspected cervical lesions and shows sufficient sensitivity to warrant further evaluation as a screening test for cervical cancer prevention programs.


Subject(s)
Mass Screening/methods , Papillomaviridae/isolation & purification , Papillomavirus Infections/diagnosis , Tumor Virus Infections/diagnosis , Uterine Cervical Neoplasms/virology , Adenocarcinoma/prevention & control , Adenocarcinoma/virology , Adult , Carcinoma in Situ/prevention & control , Carcinoma in Situ/virology , Colposcopy , DNA, Viral/analysis , Female , Humans , Logistic Models , Polymerase Chain Reaction , Predictive Value of Tests , Self Care , Sensitivity and Specificity , Specimen Handling , Urine/virology , Uterine Cervical Neoplasms/prevention & control , Vaginal Smears , Uterine Cervical Dysplasia/prevention & control , Uterine Cervical Dysplasia/virology
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