Objective: The aim of the present study was to evaluate the performance of the simultaneous detection of HIV-1 RNA, HIV-1 DNA, and HCV RNA using one dried blood spot (DBS) as an alternative sample to plasma. Method: A total of 571 paired DBS/plasma samples were collected from men who have sex with men (MSM) and injection drug users (IDUs), and serological and molecular assays were performed. Using plasma results as the reference standard, the performance of DBS tests for HIV-1 RNA, HIV-1 DNA, and HCV RNA was evaluated. Pearson's correlation coefficients and Bland-Altman analysis were performed to assess the correlation and concordance between DBS and plasma. Results: Among paired plasma/DBS samples with detectable HIV-1 RNA and HCV RNA, five samples (5/32) were not detectable in DBS, while measurable HIV-1 RNA levels were present in plasma (1.44 to 3.99 log Conclusion The performance of the simultaneous detection of HIV-1 RNA, HIV-1 DNA, and HCV RNA using one DBS was acceptable. DBS, as an alternative sample to plasma, may be a viable option for the simultaneous detection of HIV-1 RNA, HIV-1 DNA, and HCV RNA in resource-limited settings or for individuals living in areas that are difficult to access.
DNA, Viral/analysis* ; Diagnostic Tests, Routine/methods* ; Dried Blood Spot Testing/methods* ; HIV Infections/diagnosis* ; HIV-1/isolation & purification* ; Hepacivirus/isolation & purification* ; Hepatitis C/diagnosis* ; RNA, Viral/analysis* ; Sensitivity and Specificity ; Specimen Handling/methods* ; Syphilis/diagnosis* ; Treponema pallidum/isolation & purification*

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

Neurosyphilis is an infection of the brain or spinal cord that is caused by the bacterium Treponema pallidum. Syphilitic myelitis, which involves the spinal cord, is a very rare form of neurosyphilis seen in patients with syphilis. It requires differentiation from other diseases of the spinal cord, including idiopathic transverse myelitis and spinal cord infarction. Herein, we describe the presentation and diagnosis of syphilitic myelitis in a 43-year-old woman, based on a flip-flop sign and candle guttering appearance depicted in magnetic resonance imaging and laboratory tests.
Adult ; Brain ; Diagnosis ; Female ; Humans ; Infarction ; Magnetic Resonance Imaging ; Myelitis ; Myelitis, Transverse ; Neurosyphilis ; Spinal Cord ; Syphilis ; Treponema pallidum

BACKGROUND: Smoking exerts an adverse effect on the periodontal tissue by reorganizing the ecosystem of oral microorganisms and is considered to be an important factor in the development of periodontal disease. Although cross-sectional studies on smokers and non-smokers have been attempted to investigate the microbial differences in periodontal oral cavity, only few studies have been conducted to investigate the changes in oral microorganisms during smoking cessation. The purpose of this study was to investigate the changes of bacteria in saliva and gingival crevicular fluid (GCF) over a period of one year among 11 smokers trying to quit smoking.METHODS: Eleven smokers trying to quit smoking visited the clinic at baseline, two weeks, two months, four months, six months, and 12 months to give saliva and GCF samples. The amounts of 16S rRNA, Porphyromonas gingivalis, Treponema denticola, Prevotella intermedia, Fusobacterium nucleatum subsp. nucleatum, Streptococcus mutans, and Streptococcus sobrinus in saliva and GCF were quantified using real-time polymerase chain reaction TaqMan probe assay. The results were analyzed by nonparametric statistical analysis using Friedman test and Spearman correlation coefficient.RESULTS: After cessation of smoking, the amounts of 16S rRNA corresponding to P. gingivalis, F. nucleatum, P. intermedia, and T. denticola in saliva decreased and then again increased significantly. The amount of F. nucleatum 16S rRNA in GCF decreased significantly after smoking cessation. Positive correlations were observed between 16S rRNA and F. nucleatum and between F. nucleatum and T. denticola in saliva and GCF.CONCLUSION: Even if the number of subjects in this study was small, we suggest that smoking cessation may reduce the total bacterial amount and F. nucleatum in GCF. However, the results regarding changes in the microbial ecosystem due to smoking or smoking cessation were inconsistent. Therefore, further in-depth studies need to be carried out.
Bacteria ; Bacterial Load ; Cross-Sectional Studies ; Ecosystem ; Fusobacterium nucleatum ; Gingival Crevicular Fluid ; Mouth ; Periodontal Diseases ; Porphyromonas gingivalis ; Prevotella intermedia ; Real-Time Polymerase Chain Reaction ; Saliva ; Smoke ; Smoking Cessation ; Smoking ; Streptococcus mutans ; Streptococcus sobrinus ; Treponema denticola

The gastrointestinal tract is a vast reservoir for internal microbiota; it is exposed directly to various externally introduced microbes, including bacteria, viruses, parasites and others. In immune-compromised conditions, the gastrointestinal tract is frequently affected by infectious diseases that seldom manifest clinically in immune-competent hosts. Immune-compromised conditions result from a variety of reasons, including human immunodeficiency virus infection, anti-cancer chemo-radiotherapy, immune suppressive therapy for autoimmune diseases, and organ transplantations. The stomach is a relatively rare site for opportunistic infections in immune-compromised patients compared to the esophagus and colon, where esophagitis and colitis develop frequently and cause significant clinical consequences. Helicobacter pylori infection is majorly involved in gastric malfunctioning in immune-compromised patients, followed by cytomegalovirus infection. Infections by Cryptosporidium, Mycobacterium avium complex, histoplasmosis, leishmaniasis, aspergillosis, or treponema, have been reported; however, gastric involvement of these agents is extremely rare. This review discusses the general aspects and recent reports on gastric infection in immune-compromised patients.
Aspergillosis ; Autoimmune Diseases ; Bacteria ; Colitis ; Colon ; Communicable Diseases ; Cryptosporidium ; Cytomegalovirus Infections ; Esophagitis ; Esophagus ; Gastrointestinal Tract ; Helicobacter pylori ; Histoplasmosis ; HIV ; Humans ; Leishmaniasis ; Microbiota ; Mycobacterium avium Complex ; Opportunistic Infections ; Organ Transplantation ; Parasites ; Stomach ; Transplants ; Treponema

Infectious diseases of the upper gastrointestinal tract are rare, but certain bacteria including Treponema pallidum and Mycobacterium tuberculosis may infect the esophagus, stomach, and duodenum even in an immunocompetent individual. Gastric syphilis is difficult to diagnose because it presents with non-specific symptoms and diverse endoscopic findings. Nevertheless, gastric syphilis should be considered in the differential diagnosis when a patient presents with chronic inflammatory gastric lesions such as multiple erosive/ulcerative lesions and stricture or with other evidence of syphilis. Histological evaluation and specific serological tests should be performed if syphilis is suspected. Esophageal and gastroduodenal tuberculosis also exhibits non-specific clinical manifestations. The diagnosis is confirmed by mucosal biopsy or aspiration cytology revealing the presence of caseating granulomata and/or acid-fast bacilli. Mycobacterial culture and polymerase chain reaction should be incorporated into routine diagnostic studies to improve the diagnostic sensitivity. The diagnosis of tuberculosis is occasionally confirmed indirectly by an excellent response of the patient to anti-tubercular therapy.
Bacteria ; Biopsy ; Communicable Diseases ; Constriction, Pathologic ; Diagnosis ; Diagnosis, Differential ; Duodenum ; Esophagus ; Humans ; Mycobacterium tuberculosis ; Polymerase Chain Reaction ; Serologic Tests ; Stomach ; Syphilis ; Treponema pallidum ; Tuberculosis ; Upper Gastrointestinal Tract

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.

The 2016–2017 surveys on the external quality assessment scheme for serologic tests for syphilis in Korea were conducted by the Korean Association of External Quality Assessment Service. Proficiency testing (PT) panels consisting of three pooled serum samples were shipped to 430 and 432 laboratories participating in the program in the 1st and 2nd trials of 2016 and 465 and 503 laboratories in the 1st and 2nd trials of 2017, respectively. The rates of returning results were 94.2% and 50.2% for non-treponemal and treponemal tests, respectively, in the 1st trial of 2016; 94.7% and 49.5% in the 2nd trial of 2016; 94.2% and 49.5% in the 1st trial of 2017; and 92.8% and 48.7% in the 2nd trial of 2017, respectively. The most commonly used methods for non-treponemal tests were rapid plasma reagin (RPR) card test, followed by RPR turbidoimmunoassay and venereal disease research laboratory tests. The most commonly used methods for treponemal tests were Treponema pallidum particle agglutination, followed by immunochromatographic assay, Treponema pallidum latex agglutination, chemiluminescence immunoassay, and fluorescent treponemal antibody-absorption. The accuracy rates of the 2017 PT for non-treponemal and treponemal tests were 92.5%–99.8% and 93.3%–100.0%, respectively, which were significantly lower compared to the 98.4%–100.0% and 97.0%–100.0% in 2016. A possible explanation for the lower accuracy rates in the 2017 PT survey is the matrix effect caused by pooling multiple individual serum samples. These data suggest that pooling of serum samples obtained from a small number of donors may help avoid the matrix effect affecting standard materials used for syphilis serology PT.
Agglutination ; Humans ; Immunoassay ; Immunochromatography ; Korea* ; Latex ; Luminescence ; Plasma ; Serologic Tests* ; Sexually Transmitted Diseases ; Ships ; Syphilis* ; Tissue Donors ; Treponema pallidum

PURPOSE: Few studies have examined periodontal pathogens from saliva samples in periodontally healthy young adults. The purposes of this study were to determine the prevalence of periodontopathic bacteria and to quantify periodontal pathogens in saliva samples using real-time polymerase chain reaction (PCR) assays in periodontally healthy Korean young adults under 35 years of age. METHODS: Nine major periodontal pathogens were analyzed by real-time PCR in saliva from 94 periodontally healthy young adults. Quantification of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, Prevotella intermedia, Fusobacterium nucleatum, Campylobacter rectus, Peptostreptococcus anaerobius, and Eikenella corrodens was performed by DNA copy number measurement. RESULTS: F. nucleatum and E. corrodens were detected in all subjects; the numbers of positive samples were 87 (92.6%), 91 (96.8%), and 90 (95.7%) for P. gingivalis, P. anaerobius, and C. rectus, respectively. Other pathogens were also detected in periodontally healthy subjects. Analysis of DNA copy numbers revealed that the most abundant periodontal pathogen was F. nucleatum, which was significantly more prevalent than all other bacteria (P < 0.001), followed by P. anaerobius, P. gingivalis, E. corrodens, C. rectus, and T. denticola. There was no significant difference in the prevalence of each bacterium between men and women. The DNA copy number of total bacteria was significantly higher in men than in women. CONCLUSIONS: Major periodontal pathogens were prevalent in the saliva of periodontally healthy Korean young adults. Therefore, we suggest that the development of periodontal disease should not be overlooked in periodontally healthy young people, as it can arise due to periodontal pathogen imbalance and host susceptibility.
Aggregatibacter actinomycetemcomitans ; Bacteria ; Bacterial Load ; Campylobacter rectus ; Chronic Periodontitis ; DNA ; Eikenella corrodens ; Female ; Forsythia ; Fusobacterium nucleatum ; Healthy Volunteers ; Humans ; Male ; Peptostreptococcus ; Periodontal Diseases ; Porphyromonas gingivalis ; Prevalence ; Prevotella intermedia ; Real-Time Polymerase Chain Reaction ; Saliva ; Treponema denticola ; Young Adult

BACKGROUND: The syphilis diagnostic algorithms applied in different countries vary significantly depending on the local syphilis epidemiology and other considerations, including the expected workload, the need for automation in the laboratory and budget factors. This study was performed to investigate the efficacy of traditional and reverse syphilis diagnostic algorithms during general health checkups. METHODS: In total, 1,000 blood specimens were obtained from 908 men and 92 women during their regular health checkups. Traditional screening and reverse screening were applied to the same specimens using automatic rapid plasma regain (RPR) and Treponema pallidum latex agglutination (TPLA) tests, respectively. Specimens that were reverse algorithm (TPLA) reactive, were subjected to a second treponemal test performed by using the chemiluminescent microparticle immunoassay (CMIA). RESULTS: Of the 1,000 specimens tested, 68 (6.8%) were reactive by reverse screening (TPLA) compared with 11 (1.1%) by traditional screening (RPR). The traditional algorithm failed to detect 48 specimens [TPLA(+)/RPR(−)/CMIA(+)]. The median TPLA cutoff index (COI) was higher in CMIA-reactive cases than in CMIA-nonreactive cases (90.5 vs 12.5 U). CONCLUSIONS: The reverse screening algorithm could detect the subjects with possible latent syphilis who were not detected by the traditional algorithm. Those individuals could be provided with opportunities for evaluating syphilis during their health checkups. The COI values of the initial TPLA test may be helpful in excluding false-positive TPLA test results in the reverse algorithm.
Agglutination ; Automation ; Budgets ; Epidemiology ; Female ; Humans ; Immunoassay ; Latex ; Male ; Mass Screening* ; Plasma ; Syphilis* ; Syphilis, Latent ; Treponema pallidum