Combined Testing for Chlamydia, Gonorrhea, and Trichomonas by Use of the BD Max CT/GC/TV Assay with Genitourinary Specimen Types.

The BD Max CT/GC/TV (MAX) assay is a true multiplex assay for simultaneous detection of chlamydia (CT), gonorrhea (GC), and trichomonas (TV). We evaluated assay performance for women using endocervical and vaginal swabs as well as urine specimens. A total of 1,143 women were tested for CT, GC, and TV and, subsequently, another 847 (1,990 total women) for CT and GC only, with positivity rates for CT, GC, and TV of 7.1%, 2.3%, and 13.5%, respectively. In men, the performance for CT and GC was determined using only urine specimens. TV performance was not assessed in male urine samples. Among men, 181/830 (21.8%) and 108/840 (12.9%) chlamydia and gonorrhea infections, respectively, were identified. Comparator assays included BD ProbeTec Chlamydia trachomatis Qx (CTQ)/Neisseria gonorrhoeae Qx (GCQ), Hologic Aptima Combo 2 (AC2) and Aptima TV (ATV), trichomonas microscopy, and culture. MAX CT sensitivity was 99.3% (95% confidence interval [CI], 96.1% to 99.9%), 95.7% (90.8% to 98.0%), 91.5% (85.8% to 95.1%), and 96.1% (92.2% to 98.1%) for vaginal swabs, endocervical swabs, female urine samples, and male urine samples, respectively. MAX GC sensitivity was 95.5% (84.9% to 98.7%), 95.5% (84.9% to 98.7%), 95.7% (85.5% to 99.8%), and 99.1% (94.9% to 99.8%) in the same order. MAX TV sensitivity was 96.1% (91.7% to 98.2%) for vaginal swabs, 93.4% (88.3% to 96.4%) for endocervical swabs, and 92.9% (87.8% to 96.0%) for female urine samples. Specificity for all organisms across all sample types was ≥98.6%. Performance estimates for the MAX assays were consistent with estimates calculated for the comparator assays (all P values were >0.1). The availability of a CT/GC/TV multiplexed assay on a benchtop instrument with a broad menu has the potential to facilitate local sexually transmitted infection (STI) testing at smaller laboratories and may encourage expanded screening for these highly prevalent infections.

Improved Diagnosis of Acute Pulmonary Histoplasmosis by Combining Antigen and Antibody Detection.

BACKGROUND: Acute pulmonary histoplasmosis can be severe, especially following heavy inoculum exposure. Rapid diagnosis is critical and often possible by detection of antigen, but this test may be falsely negative in 17% of such cases. Antibody detection by enzyme immunoassay (EIA) may increase sensitivity and permit the measurement of immunoglobulin M (IgM) and immunoglobulin G (IgG) classes of antibodies separately. METHODS: Microplates coated with Histoplasma antigen were used for testing of serum from patients with acute pulmonary histoplasmosis and controls in the MVista Histoplasma antibody EIA. Results for IgG and IgM were reported independently. RESULTS: IgG antibodies were detected in 87.5%, IgM antibodies in 67.5%, and IgG and/or IgM antibodies in 88.8% of patients with acute pulmonary histoplasmosis in this assay, while immunodiffusion, complement fixation, and antigen testing showed sensitivities of 55.0%, 73.1%, and 67.5%, respectively (n = 80). Combining antigen and antibody detection increased the sensitivity to 96.3%. CONCLUSIONS: The MVista Histoplasma antibody EIA offers increased sensitivity over current antibody tests while also allowing separate detection of IgG and IgM antibodies and complementing antigen detection. Combining antigen and EIA antibody testing provides an optimal method for diagnosis of acute pulmonary histoplasmosis.

Multicenter evaluation of Candida QuickFISH BC for identification of Candida species directly from blood culture bottles.

Candida species are common causes of bloodstream infections (BSI), with high mortality. Four species cause >90% of Candida BSI: C. albicans, C. glabrata, C. parapsilosis, and C. tropicalis. Differentiation of Candida spp. is important because of differences in virulence and antimicrobial susceptibility. Candida QuickFISH BC, a multicolor, qualitative nucleic acid hybridization assay for the identification of C. albicans (green fluorescence), C. glabrata (red fluorescence), and C. parapsilosis (yellow fluorescence), was tested on Bactec and BacT/Alert blood culture bottles which signaled positive on automated blood culture devices and were positive for yeast by Gram stain at seven study sites. The results were compared to conventional identification. A total of 419 yeast-positive blood culture bottles were studied, consisting of 258 clinical samples (89 C. glabrata, 79 C. albicans, 23 C. parapsilosis, 18 C. tropicalis, and 49 other species) and 161 contrived samples inoculated with clinical isolates (40 C. glabrata, 46 C. albicans, 36 C. parapsilosis, 19 C. tropicalis, and 20 other species). A total of 415 samples contained a single fungal species, with C. glabrata (n = 129; 30.8%) being the most common isolate, followed by C. albicans (n = 125; 29.8%), C. parapsilosis (n = 59; 14.1%), C. tropicalis (n = 37; 8.8%), and C. krusei (n = 17; 4.1%). The overall agreement (with range for the three major Candida species) between the two methods was 99.3% (98.3 to 100%), with a sensitivity of 99.7% (98.3 to 100%) and a specificity of 98.0% (99.4 to 100%). This study showed that Candida QuickFISH BC is a rapid and accurate method for identifying C. albicans, C. glabrata, and C. parapsilosis, the three most common Candida species causing BSI, directly from blood culture bottles.

Multicenter clinical evaluation of the Xpert GBS LB assay for detection of group B Streptococcus in prenatal screening specimens.

Neonatal infection with Streptococcus agalactiae (group B Streptococcus [GBS]) is a leading cause of sepsis and meningitis in newborns. Recent guidelines have recommended universal screening of all pregnant women to identify those colonized with GBS and administration of peripartum prophylaxis to those identified as carriers to reduce the risk of early-onset GBS disease in neonates. Enriched culture methods are the current standard for prenatal GBS screening; however, the implementation of more sensitive molecular diagnostic tests may be able to further reduce the risk of early-onset GBS infection. We report a clinical evaluation of the Xpert GBS LB assay, a molecular diagnostic test for the identification of GBS from broth-enriched vaginal/rectal specimens obtained during routine prenatal screening. A total of 826 specimens were collected from women undergoing prenatal screening (35 to 37 weeks' gestation) and tested at one of three clinical centers. Each swab specimen was tested directly prior to enrichment using the Xpert GBS assay. Following 18 to 24 h of broth enrichment, each specimen was tested using the Xpert GBS LB assay and the FDA-cleared Smart GBS assay as a molecular diagnostic comparator. Results obtained using all three molecular tests were compared to those for broth-enriched culture as the gold standard. The sensitivity and specificity of the Xpert GBS LB assay were 99.0% and 92.4%, respectively, compared to those for the gold standard culture. The Smart GBS molecular test demonstrated sensitivity and specificity of 96.8% and 95.5%, respectively. The sensitivities of the two broth-enriched molecular methods were superior to those for direct testing of specimens using the Xpert GBS assay, which demonstrated sensitivity and specificity of 85.7% and 96.2%, respectively.

Detection of Trichomonas vaginalis DNA by use of self-obtained vaginal swabs with the BD ProbeTec Qx assay on the BD Viper system.

Trichomonas vaginalis is the most prevalent nonviral sexually transmitted infection worldwide, and improved diagnostic methods are critical for controlling this pathogen. Diagnostic assays that can be used in conjunction with routine chlamydia/gonorrhea nucleic acid-based screening are likely to have the most impact on disease control. Here we describe the performance of the new BD T. vaginalis Qx (TVQ) amplified DNA assay, which can be performed on the automated BD Viper system. We focus on data from vaginal swab samples, since this is the specimen type routinely used for traditional trichomonas testing and the recommended specimen type for chlamydia/gonorrhea screening. Vaginal swabs were obtained from women attending sexually transmitted disease or family planning clinics at 7 sites. Patient-collected vaginal swabs were tested by the TVQ assay, and the Aptima T. vaginalis (ATV) assay was performed using clinician-collected vaginal swabs. Additional clinician-collected vaginal swabs were used for the wet mount and culture methods. Analyses included comparisons versus the patient infection status (PIS) defined by positive results with the wet mount method or culture, direct comparisons assessed with κ scores, and latent class analysis (LCA) as an unbiased estimator of test accuracy. Data from 838 women, 116 of whom were infected with T. vaginalis, were analyzed. The TVQ assay sensitivity and specificity estimates based on the PIS were 98.3% and 99.0%, respectively. The TVQ assay was similar to the ATV assay (κ=0.938) in direct analysis. LCA estimated the TVQ sensitivity and specificity as 98.3 and 99.6%, respectively. The TVQ assay performed well using self-collected vaginal swabs, the optimal sample type, as recommended by the CDC for chlamydia/gonorrhea screening among women.

Rapid detection of Enterococcus spp. direct from blood culture bottles using Enterococcus QuickFISH method: a multicenter investigation.

The performance of a diagnostic method for detection and identification of Enterococcus spp. directly from positive blood culture was evaluated in a clinical study. The method, Enterococcus QuickFISH BC, is a second-generation peptide nucleic acid (PNA) fluorescence in situ hybridization (FISH) test, which uses a simplified, faster assay procedure. The test uses fluorescently labeled PNA probes targeting 16S rRNA to differentiate Enterococcus faecalis from other Enterococcus spp. by the color of the cellular fluorescence. Three hundred fifty-six routine blood culture samples were tested; only 2 discordant results were recorded. The sensitivities for detection of Enterococcus faecalis and non-faecalis Enterococcus were 100% (106/106) and 97.0% (65/67), respectively, and the combined specificity of the assay was 100%. The combined positive and negative predictive values of the assay were 100% (171/171) and 98.9% (185/187), respectively.

Clinical evaluation of a new Pap test-based method for screening of Chlamydia trachomatis and Neisseria gonorrhoeae using liquid-based cytology media.

OBJECTIVES: The majority of chlamydial and gonococcal infections in women are asymptomatic and, if left untreated, may result in serious sequelae. Simple and accurate testing of men and women at risk for Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (GC) is the single most effective strategy for control of sexually transmitted infections. New tests using easy-to-acquire samples, such as the Papanicolaou (Pap) test, need to be validated in an effort to expand and improve detection. The objective of this study was to determine the performance of a new nucleic acid amplification test using two liquid-based cytology media for the detection of CT and GC. METHODS: The study was conducted in two phases at 11 geographically diverse, high- and low-prevalence sites. Three endocervical reference swabs as well as an endocervical SurePath or PreservCyt liquid cytology specimen sampled with a broom or brush/spatula were collected in a randomized order from each subject. Reference endocervical swabs were tested with three Food and Drug Administration-approved methods and compared to two new automated tests, the CT Q Amplified DNA Assay (CTQ) and the GC Q Amplified DNA Assay (GCQ). RESULTS: For the SurePath phase, 1838 subjects were enrolled. The sensitivity and specificity of the CTQ assay were 95.0% and 99.7%, respectively, and the GCQ assay was 100% for both. In the PreservCyt phase, 2164 subjects were enrolled. The sensitivity and specificity of the CTQ assay were 94.1% and 99.8%, respectively, and the GCQ assay was 95.3% and 99.95%, respectively. There was no significant difference in the results. CONCLUSIONS: In this investigation, high sensitivity and specificity of the CTQ and GCQ assays were demonstrated for samples collected in either of two liquid-based cytology media when compared with endocervical swabs. The results were similar in both collection methods (broom or brush/spatula) and in high- and low-risk populations.

Multicenter evaluation of the Staphylococcus QuickFISH method for simultaneous identification of Staphylococcus aureus and coagulase-negative staphylococci directly from blood culture bottles in less than 30 minutes.

A novel rapid peptide nucleic acid fluorescence in situ hybridization (FISH) method, Staphylococcus QuickFISH, for the direct detection of Staphylococcus species from positive blood culture bottles was evaluated in a multicenter clinical study. The method utilizes a microscope slide with predeposited positive- and negative-control organisms and a self-reporting 15-min hybridization step, which eliminates the need for a wash step. Five clinical laboratories tested 722 positive blood culture bottles containing gram-positive cocci in clusters. The sensitivities for detection of Staphylococcus aureus and coagulase-negative staphylococci (CoNS) were 99.5% (217/218) and 98.8% (487/493), respectively, and the combined specificity of the assay was 89.5% (17/19). The combined positive and negative predictive values of the assay were 99.7% (696/698) and 70.8% (17/24), respectively. Studies were also performed on spiked cultures to establish the specificity and performance sensitivity of the method. Staphylococcus QuickFISH has a turnaround time (TAT) of <30 min and a hands-on time (HOT) of <5 min. The ease and speed of the method have the potential to improve the accuracy of therapeutic intervention by providing S. aureus/CoNS identification simultaneously with Gram stain results.

Clinical evaluation of the BD ProbeTec™ Neisseria gonorrhoeae Qx amplified DNA assay on the BD Viper™ system with XTR™ technology.

BACKGROUND: The excellent sensitivity and specificity of commercially available nucleic acid amplification tests (NAATs) for the identification of Neisseria gonorrhoeae have been demonstrated. This study evaluated the performance of the BD ProbeTec™ N. gonorrhoeae Q (GCQ) Amplified DNA Assay on the BD Viper™ System with XTR™ Technology in a multicenter study. METHODS: Specimens were collected at 7 geographically diverse clinical sites from 1846 women and men attending sexually transmitted disease, family planning, and obstetrics and gynecology clinics. There were 1768 evaluable participants, 994 women and 774 men. GCQ results from female endocervical, self-collected vaginal, male urethral swab specimens, and male and female neat (unpreserved) urine specimens, as well as those obtained using the urine preservative transport (UPT) tube for the GCQ assay were compared with patient infected status (PIS). For each participant, PIS was determined based on the combined results from the reference assays Aptima Combo 2® (AC2) and BD ProbeTec™ ET GC Amplified DNA Assay (PT). RESULTS: The sensitivity versus PIS for endocervical, vaginal, and female UPT urine, and female neat urine samples was 98.5%, 100.0%, 98.5%, and 96.9%, respectively; the specificity was 99.7%, 99.1%, 99.7%, and 99.5%, respectively. The sensitivity versus PIS for male urethral swabs and both male UPT and neat urine was 100.0%, with specificities of 99.1% for the urethral swab and UPT urine and 98.9% for the neat urine. The overall GCQ assay performance was not statistically different from that of AC2 or PT. CONCLUSIONS: The GCQ assay demonstrated performance characteristics comparable with other commercially available nucleic acid-based tests such as AC2 and PT. Vaginal swabs, endocervical swabs, urethral swabs, and urine specimens may all be used for gonorrhea screening.

A multicenter evaluation of tests for diagnosis of histoplasmosis.

BACKGROUND: The sensitivity of the MVista Histoplasma antigen enzyme immunoassay (MiraVista Diagnostics) has been evaluated in disseminated histoplasmosis in patients with AIDS and in the "epidemic" form of acute pneumonia. Moreover, there has been no evaluation of the sensitivity of antigenemia detection in disseminated histoplasmosis after the implementation of methods to dissociate immune complexes and denature released antibodies. The goal of this study was to determine the sensitivity of the current antigen assay in different categories of histoplasmosis. METHODS: Urine and serum specimens obtained from 218 patients with histoplasmosis and 229 control subjects, including 30 with blastomycosis, were tested. RESULTS: Antigenuria was detected in 91.8% of 158 patients with disseminated histoplasmosis, 83.3% of 6 patients with acute histoplasmosis, 30.4% of 46 patients with subacute histoplasmosis, and 87.5% of 8 patients with chronic pulmonary histoplasmosis; antigenemia was present in 100% of 31 tested cases of disseminated histoplasmosis. Among patients with disseminated cases, antigenuria was detected more often and at higher concentrations in immunocompromised patients and those with severe disease. Specificity was 99.0% for patients with nonfungal infections (n = 130) and in healthy subjects (n = 69), but cross-reactivity occurred in 90% of patients with blastomycosis. CONCLUSIONS: The sensitivity of antigen detection in disseminated histoplasmosis is higher in immunocompromised patients than in immunocompetent patients and in patients with more severe illness. The sensitivity for detection of antigenemia is similar to that for antigenuria in disseminated infection.

Clinical evaluation of the BD ProbeTec™ Chlamydia trachomatis Qx amplified DNA assay on the BD Viper™ system with XTR™ technology.

BACKGROUND: This study evaluated the performance of the BD ProbeTec Chlamydia trachomatis Q (CTQ) Amplified DNA Assay on the BD Viper System with XTR Technology in a multicenter study. METHODS: Specimens were collected at 7 geographically diverse clinical sites from 1538 women and men attending sexually transmitted disease, family planning, and obstetrics and gynecology clinics. There were 1465 evaluable participants, 993 women and 472 men. CTQ assay results from female endocervical, self-collected vaginal, male urethral swab specimens, and male and female neat (unpreserved) urine specimens as well as those obtained using the Urine Preservative Transport (UPT) tube for the CTQ assay were compared with patient-infected status (PIS). PIS was determined based on the combined results from Aptima Combo 2 and BD ProbeTec ET CT Amplified DNA Assay. RESULTS: The sensitivity versus PIS for endocervical, vaginal, and both female urine samples was 91.3%, 96.5%, and 93.0%, respectively. The specificity for the same specimen types was 98.3%, 99.2%, and 99.4% (urine neat) and 99.2% (UPT), respectively. The sensitivity versus PIS for male urethral swabs and both male neat and UPT urine were 92.1% and 98%, respectively, with specificities of 98.4%, 99.2%, and 98.1%, respectively. CONCLUSIONS: The CTQ assay demonstrated performance characteristics comparable with other commercially available nucleic acid-based tests such as Aptima Combo 2 and BD ProbeTec ET CT-Amplified DNA assay. Vaginal swabs and male urine specimens, the sample types recommended by the Centers for Disease Control for chlamydia screening, both performed at least as well as other sample types evaluated.

Multicenter evaluation of the LightCycler methicillin-resistant Staphylococcus aureus (MRSA) advanced test as a rapid method for detection of MRSA in nasal surveillance swabs.

The rate of methicillin-resistant Staphylococcus aureus (MRSA) infection continues to rise in many health care settings. Rapid detection of MRSA colonization followed by appropriate isolation can reduce transmission and infection. We compared the performance of the new Roche LightCycler MRSA advanced test to that of the BD GeneOhm MRSA test and culture. Double-headed swabs were used to collect anterior nasal specimens from each subject. For both tests, DNA was extracted and real-time PCR was performed according to manufacturer's instructions. For culture, one swab of the pair was plated directly to CHROMagar MRSA. The swab paired with the BD GeneOhm MRSA test was also placed into an enrichment broth and then plated to CHROMagar MRSA. Colonies resembling staphylococci were confirmed as S. aureus by standard methods. Discrepant specimens had further testing with additional attempts to grow MRSA as well as sample amplicon sequencing. Agreement between results for the two swabs was 99.3% for those with valid results. A total of 1,402 specimens were tested using direct culture detection of MRSA as the gold standard; 187 were culture positive for MRSA. The LightCycler MRSA advanced test had relative sensitivity and specificity of 95.2% (95% confidence interval [CI]: 91.1% to 97.8%) and 96.4% (95% CI: 95.2% to 97.4%), respectively. The BD GeneOhm assay had relative sensitivity and specificity of 95.7% (95% CI: 91.7% to 98.1%) and 91.7% (95% CI: 90.0% to 93.2%), respectively. Following discrepancy analysis, the relative sensitivities of the LightCycler MRSA advanced test and the BD GeneOhm MRSA assay were 92.2 and 93.2%, respectively; relative specificities were 98.9 and 94.2%, respectively. Specificity was significantly better (P<0.001) with the LightCycler MRSA advanced test. The sensitivity of direct culture was 80.4%. The LightCycler MRSA advanced test is a useful tool for sensitive and rapid detection of MRSA nasal colonization.

Diagnosis of histoplasmosis by antigen detection in BAL fluid.

BACKGROUND: Detection of antigen in BAL is useful for diagnosis of histoplasmosis. The MVista Histoplasma antigen enzyme immunoassay has been modified to permit quantification. The purpose of this study is to compare the sensitivity of the quantitative antigen detection assay with cytopathology and culture of BAL specimens. METHODS: BAL from patients with histoplasmosis who were evaluated at the Indiana University Medical Center and controls without histoplasmosis were studied. BAL fluid was tested in the quantitative Histoplasma antigen assay. RESULTS: Antigen was detected in the BAL in 93.5% of patients with histoplasmosis, 80% with blastomycosis, and 0% of controls with nonfungal infections. Antigen was detected in the urine of 79% and serum in 65% of patients with histoplasmosis. Cytopathology was positive in 48% and culture in 48% of patients with histoplasmosis, and 40% and 60% of patients with blastomycosis, respectively. Serology was positive in 65%. Combining BAL antigen detection and BAL cytopathology, both methods for rapid diagnosis, the sensitivity was 96.8% in histoplasmosis and 80% in blastomycosis. CONCLUSIONS: Detection of antigen in BAL complements antigen detection in serum and urine as an objective diagnostic test for histoplasmosis.

Detection of Histoplasma capsulatum antigenuria by ultrafiltration of samples with false-negative results.

Patients with histoplasmosis may test falsely negative for Histoplasma capsulatum antigenuria. In some cases antigen is present at levels below the assay's detection limit, and ultrafiltration could improve sensitivity. Antigen was detected following ultrafiltration in 73.8% of falsely negative specimens versus 2% of controls. Ultrafiltration improved sensitivity with a small reduction in specificity.

Histoplasmosis as a cause for a positive Fungitell (1 --> 3)-beta-D-glucan test.

We evaluated the Fungitell beta-glucan (BG) test with specimens from patients with presumed histoplasmosis. The sensitivity of the test was 87% in histoplasmosis cases and had a specificity of 68% with controls. Histoplasmosis should be considered as a possible cause for a positive BG test, but such results may be found with many other conditions that are clinically similar to this fungal disease. Therefore, there is a need to conduct confirmatory tests for histoplasmosis in the appropriate clinical setting.

Diagnosis of pulmonary histoplasmosis and blastomycosis by detection of antigen in bronchoalveolar lavage fluid using an improved second-generation enzyme-linked immunoassay.

Antigen detection is a useful adjunct for the diagnosis of histoplasmosis. The purpose of this study was to evaluate antigen detection in bronchoalveolar lavage (BAL) fluid using an improved second-generation Histoplasma antigen assay. Antigen was detected in 16 of 19 (84%) cases of histoplasmosis and 5 of 6 (83.3%) blastomycosis cases using the second-generation assay vs. 13 of 19 (68%) and 4 of 6 (66.7%), respectively, in the original assay. Ten-fold concentration permitted detection of antigen in an additional case of histoplasmosis and another with blastomycosis, for an overall sensitivity of 23 of 25 (92.0%). Specificity was 98.2% in both assays in controls with other pulmonary infections. These findings support the diagnostic utility of the second-generation assay in patients with pulmonary histoplasmosis and blastomycosis.

Vaginal swabs are the specimens of choice when screening for Chlamydia trachomatis and Neisseria gonorrhoeae: results from a multicenter evaluation of the APTIMA assays for both infections.

BACKGROUND: Vaginal swabs were recently U.S. Food and Drug Administration-cleared for detecting Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (GC) using Gen-Probe Incorporated's APTIMA COMBO2 Assay (AC2). We assessed the APTIMA CT Assay (ACT) for CT, APTIMA GC Assay (AGC) for GC, and AC2 for both organisms using patient- and clinician-collected vaginal swabs. METHOD: Women attending family planning, obstetrics and gynecology, or sexually transmitted disease (STD) clinics had first-catch urines (FCUs), patient-collected vaginal swabs, clinician-collected vaginal swabs, and endocervical swabs tested by ACT, AGC, and AC2. A second endocervical swab and FCU were tested using BD ProbeTec (Becton Dickinson) for CT and GC. We calculated sensitivity and specificity using vaginal swabs to detect CT and GC. RESULTS: Of 1,464 subjects enrolled, 180 had CT and 78 GC. ACT sensitivities and specificities for patient-collected vaginal swabs were 98.3% and 96.5%, respectively; for clinician-collected vaginal swabs, 97.2% and 95.2%, respectively. AGC sensitivities and specificities for patient-collected vaginal swabs were 96.1% and 99.3%, respectively; for clinician-collected vaginal swabs, 96.2% and 99.3%, respectively. AC2 results were similar. If an FCU tested positive for CT or GC, >94% of matching vaginal swabs were positive. Positive endocervical swabs showed slightly less concordance (>90% and >88%, respectively). More infected patients were identified using vaginal swabs than FCUs. With AC2, 171 CT-infected patients were identified using FCUs and 196 using patient-collected vaginal swabs. This difference was more pronounced for CT than for GC. CONCLUSIONS: Vaginal swab specimens allowed sensitive and specific detection of CT and GC in the APTIMA assays. Vaginal swabs identified as many infected patients as endocervical swabs and more than FCUs, and may well be the specimen of choice for screening.

Women find it easy and prefer to collect their own vaginal swabs to diagnose Chlamydia trachomatis or Neisseria gonorrhoeae infections.

BACKGROUND: Self-collected specimens can be used to screen asymptomatic women for Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (GC). We surveyed women's opinions on ease and preferences as to sampling after collecting their own vaginal swab and urine and a physician collection of vaginal swab and cervical swab. METHODS: In 7 North American cities, a questionnaire was used for women after they participated in a clinical trial of nucleic acid amplification testing of various specimens. A total of 1,090 women consenting to gynecologic sampling for CT and GC (82% of those sampled) volunteered to complete the survey. We analyzed the data for ease of self-collection and preferences for a vaginal swab, urine, or cervical swab. RESULTS: The average age was 26.6 years; 59.6% were black, 25.5% white, 11% Hispanic, 1.9% Asian, and 2% unknown. Thirty-five percent had more than one sex partner in the past 6 months, 84.9% had been previously tested for a sexually transmitted infection (STI), and 49.2% had experienced an STI. A total of 90.4% found it very easy to self-collect a vaginal swab. This was not influenced by age, education, or study site. Seventy-six percent preferred a vaginal swab over a pelvic examination, 60% over a urine collection, and 94% indicated that they would be tested more often if a vaginal swab was available. CONCLUSION: Self-collected vaginal swabs were easy to collect and patients preferred them over urine and cervical swabs.

Clinical evaluation of affirm VPIII in the detection and identification of Trichomonas vaginalis, Gardnerella vaginalis, and Candida species in vaginitis/vaginosis.

OBJECTIVE: To compare the Affirm VPIII Microbial Identification Test for detection and identification of Candida species, Gardnerella vaginalis and Trichomonas vaginalis to clinical and microscopic criteria commonly used to diagnose vaginitis. METHODS: Women that were symptomatic for vaginitis/vaginosis and asymptomatic women being seen for routine obstetric or gynecological care were included in this study. Women treated with antibiotics or antifungals within one week or women who had douched within 24 hours were excluded. Two vaginal swab specimens were simultaneously obtained from each patient, one swab was placed in sterile physiological saline for immediate microscopic wet mount examination and KOH testing. The other swab was placed in the Affirm collection tube for Affirm VPIII testing based on previously demonstrated methods. RESULTS: The Affirm assay was significantly more likely to identify Gardnerella and Candida than wet mount. 190 (45%) were positive for Gardnerella by Affirm compared to 58 (14%) by wet mount; 45 (11%) were positive for Candida by Affirm compared to 31 (7%) by wet mount; and 30 (7%) were positive for Trichomonas by Affirm compared to 23 (5%) by wet mount. Symptomatic women were significantly more likely to be positive by Affirm only (23% vs. 10%), wet mount only (3% vs. 2%) or Affirm and wet mount (15% vs. 1%). Asymptomatic women were significantly more likely to be negative for Affirm and wet mount (43% vs. 5%). CONCLUSIONS: The Affirm VPIII test is a more sensitive diagnostic test for detection and identification of symptomatic vaginitis/vaginosis than conventional clinical examination and wet mount testing.