Detection of Treponema pallidum in whole blood samples of patients with syphilis by the polymerase chain reaction

Syphilis is caused by the bacterium Treponema pallidum. The diagnosis is based on clinical data and serological analysis; however, the sensitivity and specificity of such tests may vary depending on the type of test and stage of the infection. In order to overcome this premise, this study utilized the polymerase chain reaction (PCR) for the detection of T. pallidum DNA in whole blood samples of patients with syphilis. The blood samples from patients with or without symptoms of syphilis, but with positive results in enzyme-linked immunosorbent assay (ELISA), were included in this study. A venereal disease research laboratory (VDRL) test was performed for all collected sera samples. For PCR, the T. pallidum DNA was extracted from the collected blood samples and a specific primer set was designed to amplify 131 nucleotides of polA (Tp0105). The specificity of the primers was evaluated with the DNA of 17 different pathogens. From a total of 314 blood samples reactive in ELISA, 58.2% (183/314) of the samples were reactive in the VDRL test. In the PCR, 54% (168/314) of the ELISA-reactive samples were positive. In both tests (VDRL and PCR) 104 samples were positive. Of 104 positive samples for both tests, 71 were at the latent stage. Based on these results, it can be concluded that PCR with the designed set of primers can be utilized as a diagnostic method for T. pallidum detection in blood samples of patients with syphilis, especially those with latent infection. In addition, it can be utilized as a supplement for serological methods to improve the diagnosis of syphilis

Epidemiological study in Brazilian women highlights that syphilis remains a public health problem

yphilis, an infectious disease considered a global public health concern, can cause stillbirths and neonatal deaths. This highlights the importance of continuous surveillance studies among women of reproductive age. A cross-sectional study was carried out to analyze the prevalence and risk factors associated with Treponema pallidum infection in women assisted by primary health care units in Dourados, a city located in Mato Grosso do Sul State, Brazil, which borders Paraguay. A questionnaire was applied to a population-based sample, blood samples were collected for syphilis testing and multivariable analyses were performed to screen associations with T. pallidum infection. The prevalence of T. pallidum infection was 6.04%. Bivariate analysis showed that women referring multiple sexual partners (c2: 6.97 [p=0.014]), income less 2 minimal wages (c2: 15.93 [p=0.003]), who did not have high school (c2: 12.64 [p=0.005]), and reporting history of STIs (c2: 7.30 [p=0.018]) are more likely to have syphilis. In the multivariate analysis, a highest prevalence ratio was observed in women with income less than 2 minimal wages (PR: 0.96 [95% CI: 0.85 - 0.97]), and who did not have high school (PR: 0.94 [95% CI: 0.90 - 0.98]). In addition, 80% of the women reported irregular use of condoms and 63.89% declared having sexual intercourses with multiple partners, which creates more opportunities for the transmission of the infection. These results highlight the need for healthcare systems to implement initiatives to monitor syphilis screening and the commitment of patients and their sexual partners to the treatment in order to achieve a decrease of new cases

Synergistic effects of Cinnamomum cassia L. essential oil in combination with polymyxin B against carbapenemase-producing Klebsiella pneumoniae and Serratia marcescens.

Multidrug resistance prompts the search for new sources of antibiotics with new targets at bacteria cell. To investigate the antibacterial activity of Cinnamomum cassia L. essential oil (CCeo) alone and in combination with antibiotics against carbapenemase-producing Klebsiella pneumoniae and Serratia marcescens. The antimicrobial susceptibility of the strains was determined by Vitek® 2 and confirmed by MALDI-TOF/TOF. The antibacterial activity of CCeo and its synergism with antibiotics was determined using agar disk diffusion, broth microdilution, time-kill, and checkboard methods. The integrity of the bacterial cell membrane in S. marcescens was monitored by protein leakage assay. CCeo exhibited inhibitory effects with MIC = 281.25 μg.mL-1. The association between CCeo and polymyxin B showed a decrease in terms of viable cell counts on survival curves over time after a 4 hour-treatment with a FIC index value of 0.006. Protein leakage was observed with increasing concentrations for CCeo and CCeo + polymyxin B treatments. CCeo showed antibacterial activity against the studied strains. When associated with polymyxin B, a synergistic effect was able to inhibit bacterial growth rapidly and consistently, making it a potential candidate for the development of an alternative treatment and drug delivery system for carbapenemase-producing strains