OBJECTIVE: To Establish the shielding threshold value of TP antibody ELISA for unpaid blood donors, so as to shield true positive blood donors from returning to team management. METHODS: The real serological status of 517 samples with anti-TP ELISA reactivity was determined by confirmation test of Treponema pallidum particle agglutination (TPPA). The shielding threshold of TP antibody was preliminarily determined by using 99% specificity of ROC and 95% positive predictive value of percentile method, respectively. 283 TP antibody reactivity specimens routinely tested in our laboratory were selected to determine the applicability of the initial shielding values obtained by the two methods, and finally to determine the shielding threshold values of TP antibody donors. RESULTS: The specific S/CO values of reagent A 99% were 13.33-16.18, that of reagent B 99% was 6.34, that of reagent B 99% was 13.17-19.85, and that of 95% was 6.62. Empirical evidence: 99% specific threshold shielding true positive rates of reagents A and B were 100%, 95% positive expected value shielding true positive rates were 98.4%, 99%. Final determination of 99% specific shielding threshold as a low value of blood donors shielding threshold. The shielding limits of reagent A and B were 13.33 and 13.17. CONCLUSION The shielding threshold of TP antibody ELISA for blood donors established in this study can help to reduce the number of blood donors returning to team management.
Blood Donors ; Enzyme-Linked Immunosorbent Assay ; Humans ; Syphilis ; Syphilis Serodiagnosis ; Treponema pallidum

OBJECTIVETo evaluate the accuracy and precision of 2 kinds of anti-treponema pallidum (anti-TP) ELISA reagents in our laboratory for detecting the anti-TP in voluntary blood donors, so as to provide the data support for use of ELISA reagents after introduction of chemiluminescene immunoassay (CLIA).

METHODSThe route detection of anti-TP was performed by using 2 kinds of ELISA reagents, then 546 responsive positive samples detected by anti-TP ELISA were collected, and the infections status of samples confirmed by treponema pallidum particle agglutination (TPPA) test was identified. The confirmed results of responsive samples detected by 2 kinds of anti-TP ELISA reagents were compared, the accuracy of 2 kinds of anti-TP ELISA reagents was analyzed by drawing ROC and comparing area under curve (AUC), and precision of 2 kinds of anti-TP ELISA reagents was compared by statistical analysis of quality control data from 7.1 2016 to 6.30 2017.

RESULTSThere were no statistical difference in confirmed positive rate of responsive samples and weak positive samples between 2 kinds of anti-TP ELISA reagents. The responsive samples detected by 2 kinds of anti-TP ELISA reagents accounted for 85.53%(467/546) of all responsive samples, the positive rate confirmed by TPPA test was 82.87%. 44 responsive samples detected by anti-TP ELISA reagent A and 35 responsive samples detected by anti-TP ELISA reagent B were confirmed to be negative by TPPA test. Comparison of AUC showed that the accuracy of 2 kinds of anti-TP ELISA reagents was more high, the difference between 2 reagents was not statistically significant. The coefficient of variation (CV) of anti-TP ELISA reagent A and B was 14.98% and 18.04% respectively, which met the precision requirement of ELISA test.

CONCLUSIONThe accuracy and precision of 2 kinds of anti-TP ELISA reagents used in our laboratory are similar, and using any one of anti-TP ELISA reagents all can satisfy the requirements of blood screening.

Blood Donors ; Enzyme-Linked Immunosorbent Assay ; Humans ; Syphilis Serodiagnosis ; Treponema pallidum

Objective: To investigate the changes of proportion on both consistent condom use and syphilis infection among low-fee female sex workers aged 35 and above (LFSW), in order to provide evidence for targeted intervention strategies. Methods: A total of six cities-Liuzhou city and Pingnan couty of Guigang city of Guangxi Zhuang Autonomous Region, Jinghong city of Xishuangbanna Dai autonomous prefecture and Dali city of Dali Bai autonomous prefecture of Yunnan province, Zhangjiajie city and Jianghua Yao autonomous county of Yongzhou city Hunan province were involved in this study, with 60 eligible participants needed in each city, estimated through a pre-study. The first cross-sectional survey was completed from October 2012 to January 2013. Face-to-face questionnaire interview was carried out to collect information on socio-demography, work-related information and condom use situation. Blood was collected for syphilis testing. The second cross-sectional survey was carried out from June to September, 2015 under the same procedure. Results: A total of 371 and 403 eligible participants were included in the first and second survey, respectively. When comparing the two surveys, we noticed that the average age showed a slight change, from 42.4 years to 43.8 years old (t=3.537, P<0.001) and the average price for every commercial sex exchange increased from 36.8 RMB to 49.5 RMB (t=11.961, P<0.001). In the first survey, 46.9% (174/371) of the participants had more than two years of experience working as LFSW, compared to 61.3% (247/403) in the second survey (χ(2)=16.125, P<0.001). Also, 46.9% (174/371) of the participants consistently used condoms with clients in the past month in the first survey versus 64.3% (259/403) (χ(2)=23.641, P<0.001) in the second one. Rates of syphilis infection were found from 15.9% (59/371) in the first survey reduced to 7.2% (29/403) in the second survey (χ(2)=14.533, P<0.001). Conclusion: Compared with the first survey, the proportion of consistent condoms use showed an increase. Although the proportion of syphilis infection decreased in the second survey, the scope did not meet the criteria on syphilis, set by the government. Targeted intervention strategies on condom promotion and syphilis control should be implemented consistently in this population.
Adult ; China/epidemiology* ; Condoms/trends* ; Cross-Sectional Studies ; Female ; Humans ; Prevalence ; Risk Factors ; Safe Sex ; Sex Work ; Sex Workers ; Sexually Transmitted Diseases/epidemiology* ; Surveys and Questionnaires ; Syphilis/prevention & control* ; Syphilis Serodiagnosis

BACKGROUND: Automated analyzer-based nontreponemal serological tests for syphilis (STS) have been used for several decades. OBJECTIVE: In this study, we evaluated serological responses to treatment and proposed clinical guidelines for automated STS. METHODS: This retrospective cohort study analyzed human immunodeficiency virus-negative syphilis patients who were diagnosed with automated rapid plasma reagin (auto RPR) tests as a nontreponemal STS, and who also received the fluorescent treponemal antibody-absorption test as a confirmatory test. The ratio of auto RPR values after treatment against those at baseline was defined as the auto RPR ratio for the analysis of the serological response to treatment. The cutoff value for reliable seroreversion prediction was assessed with receiver-operating-characteristic curves. RESULTS: Overall, 89.7% of participants (78/87) seroreverted and 10.3% of participants (9/87) remained serofast during the two-year follow-up period. We were unable to describe trends in the changes among auto RPR values within six months after treatment because of high variation. All of the patients who had an auto RPR ratio ≥1.0 after six months continuously had positive serologic results during their 24-month follow-up and were classified as a serofast group. The receiver-operating-characteristic curves revealed a 25% reduction in auto RPR values nine months after treatment and predicted seroreversion with a sensitivity of 96.2% and a specificity of 100%. CONCLUSION: The most important primary checkpoint for syphilis treatment response is an increase in automated nontreponemal STS six months after treatment. Thus, we recommend monitoring the treatment response with an auto RPR.
Cohort Studies ; Fluorescent Treponemal Antibody-Absorption Test ; Follow-Up Studies ; Humans* ; Plasma ; Retrospective Studies ; Sensitivity and Specificity ; Serologic Tests* ; Sexually Transmitted Diseases ; Syphilis Serodiagnosis ; Syphilis* ; Treponema pallidum

BACKGROUNDThe false positive in conventional syphilis serological test was found in patients with multiple myeloma (MM).

OBJECTIVETo investigate the relationship between the M-protein of patients with MM and the false positive in conventional syphilis serologic test.

METHODSThe M-protein of 68 MM cases was typed with immunofixation electrophoresis and 68 cases of MM were screened with non-specific and specific syphilis serologic tests, then the samples with syphilic serological positive were chosen and confirmed with immonobloting test, finally the relationship between M protein of MM and the false positive of syphilis serological test were analysed.

RESULTSFour out of 68 cases showed the positive in syphilis serological test and further were confimed to be false positive by immunoblotting test, the false positive rate was nearly 6%. The M-protein of MM patients in our hospital mostly possessed IgG, κ type, followed by IgA, κ type, light chain κ type. In general, κ : λ = 2.4 : 1. Among samples of 4 cases with syphilis serological positive 2 cases were of IgG and κ type, 1 case was of IgG, λ type, another 1 case was IgA, κ type.

CONCLUSIONThe M-protein of IgG and IgA types in MM patients results in syphilis serological false positive reaction. The clinicians and laboratorial technicians should pay a great attention to screen the MM patients for the false positive syphilis serological test so as to avoid the misdiagnosis and subsequent embarassment.

Diagnostic Errors ; False Positive Reactions ; Humans ; Immunoglobulin A ; classification ; Immunoglobulin G ; classification ; Multiple Myeloma ; diagnosis ; Myeloma Proteins ; metabolism ; Syphilis ; diagnosis ; Syphilis Serodiagnosis

No abstract available.
Anti-Bacterial Agents/therapeutic use ; Diagnosis, Differential ; Electroretinography ; Eye Infections, Bacterial/*diagnosis/drug therapy ; Fluorescein Angiography ; Humans ; Male ; Middle Aged ; Penicillin G Benzathine/therapeutic use ; Retinitis/*diagnosis/drug therapy ; Scotoma/*diagnosis/drug therapy ; Syphilis/*diagnosis/drug therapy ; Syphilis Serodiagnosis ; Tomography, Optical Coherence ; Visual Acuity/physiology

Syphilis is a sexually transmitted disease caused by Treponema pallidum. The prevalence of this disease has recently increased worldwide. However, pulmonary involvement in secondary syphilis is extremely rare. A 51-year-old heterosexual male patient presented with multiple pulmonary nodules with reactive serology from the Venereal Disease Research Laboratory test and positive fluorescent treponemal antibody absorption testing. A hematogenous metastatic malignancy was suspected and an excisional lung biopsy was performed. Histopathological examination showed only central necrosis with abscess and plasma cell infiltration, but no malignant cells. The patient reported sexual contact with a prostitute 8 weeks previously and a penile lesion 6 weeks earlier. Physical examination revealed an erythematous papular rash on the trunk. Secondary syphilis with pulmonary nodules was suspected, and benzathine penicillin G, 2.4 million units, was administered. Subsequently, the clinical signs of syphilis improved and the pulmonary nodules resolved. The final diagnosis was secondary syphilis with pulmonary nodular involvement.
Anti-Bacterial Agents/therapeutic use ; Biopsy ; Diagnosis, Differential ; Humans ; Lung Neoplasms/diagnosis ; Male ; Middle Aged ; Multimodal Imaging ; Multiple Pulmonary Nodules/diagnosis/drug therapy/*microbiology ; Penicillin G Benzathine/therapeutic use ; Predictive Value of Tests ; Prostitution ; Respiratory Tract Infections/diagnosis/drug therapy/*microbiology/transmission ; Sex Workers ; Syphilis/*diagnosis/drug therapy/*microbiology/transmission ; Syphilis Serodiagnosis ; Tomography, X-Ray Computed ; Treatment Outcome ; Unsafe Sex

Syphilis, a chronic bacterial infection caused by the spirochete Treponema pallidum subsp. pallidum, remains a public health concern worldwide. Syphilis control is largely dependent upon early identification and prompt treatment. The diagnosis of syphilis is mainly based on laboratory tests, especially serology and dark-field microscopy. In recent years, recombinant Treponema pallidum antigen-based rapid tests, polymerase chain reaction, and immunoglobulin M antibody detection have also shown certain sensitivities and specificities for syphilitic patients at different stages.
Antigens, Bacterial ; blood ; Humans ; Immunoglobulin M ; blood ; Polymerase Chain Reaction ; methods ; Sensitivity and Specificity ; Syphilis ; blood ; diagnosis ; Syphilis Serodiagnosis ; Treponema pallidum ; immunology ; isolation & purification

OBJECTIVETo investigate the application value of toluidine red unheated serum test (TRUST), treponema pallidum enzyme-linked immunosorbent assay (TP-ELISA) and treponema pallidum particle agglutination assay (TPPA) in the serologic diagnosis of syphilis.

METHODSWe collected serum samples from 12 622 inpatients, 2 253 outpatients and 1 500 subjects in the medical examination center, and screened them by TRUST and TP-ELISA, followed by quantitative tests using TRUST and TPPA.

RESULTSAmong the 16 375 cases, clinically diagnosed syphilis was confirmed in 384, with a positive rate of 100% either by TRUST (1:2 -1 :16) or TPPA (1:80 - 1:2 560), and 92.2% by TP-ELISA.

CONCLUSIONTP-ELISA and TRUST should be simultaneously used for syphilis screening, but not TP-ELISA alone, and the results should be confirmed by TPPA. The combination of the three methods plays a valuable role in reducing the misdiagnosis and missed diagnosis, and contributes to the early and accurate diagnosis of syphilis.

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Child ; Child, Preschool ; Enzyme-Linked Immunosorbent Assay ; methods ; Humans ; Infant ; Infant, Newborn ; Middle Aged ; Syphilis ; blood ; diagnosis ; Syphilis Serodiagnosis ; methods ; Treponema pallidum ; Young Adult

BACKGROUND: We analyzed the positive rates of Mediace Rapid Plasma Reagin (RPR) (Sekisui, Japan) and Mediace Treponema pallidum Latex Agglutination (TPLA) (Sekisui) assays. Positive results were compared to those of immunochromatography assay (ICA) and fluorescent treponemal antibody absorption (FTA-ABS) tests. METHODS: We used samples of patients visited at a university hospital from April 2010 to May 2011. The rates of positive results were calculated with 36,343 RPR results and 5,934 TPLA results. In addition, 237 positive samples with Mediace RPR or TPLA were re-tested with ICA and FTA-ABS. Mediace RPR and TPLA tests were performed with Toshiba 200-FR Neo (Toshiba, Japan). RESULTS: The rates of positive results were 0.47% (169/36,343) and 3.52% (209/5,934) with RPR and TPLA, respectively. Among the 237 sera that tested positive with RPR or TPLA, 76 were RPR(+)/TPLA(+), 28 were RPR(+)/TPLA(-), and 133 were RPR(-)/TPLA(+). When compared to the ICA results, 86.84% (66/76) of the RPR(+)/TPLA(+) sera were ICA(+), 3.57% (1/28) of the RPR(+)/TPLA(-) sera were ICA(+), and 54.89% (73/133) of the RPR(-)/TPLA(+) sera were ICA(+). Only 67.11% of the TPLA(+) sera demonstrated positive FTA-ABS results. However, 100% of the TPLA(-) sera yielded negative FTA-ABS results. ICA and FTA-ABS had a 96.59% positive agreement rate and an 80.68% negative agreement rate. CONCLUSIONS: These results demonstrate that Mediace TPLA has a low positive agreement rate with FTA-ABS. Although Mediace RPR and TPLA have advantages associated with automated methods, positive results should be confirmed with other treponemal tests, due to the high false positive rates.
Absorption ; Agglutination ; Humans ; Immunochromatography ; Latex ; Plasma ; Syphilis Serodiagnosis ; Treponema ; Treponema pallidum