Acquired syphilis with flat condyloma in a 3 year-old girl: A case report

The incidence of syphilis in young children is very low, with acquired syphilis exceptionally rare. A 3 year-old girl presented to our service with a reddish-brown rash on the external genitals and perianal area. The rash had been apparent for a period of 1 week. The girl was asymptomatic and had no history of sexual contact. Syphilis was suspected and the Treponema pallidum particle agglutination test (TPPA) was found to be positive, as well as the rapid plasma regin ring card test (RPR), with a titer of 1:64. The girl was diagnosed with toddler acquired secondary syphilis. The girl was cured after three treatments with penicillin. This report points out the need for clinicians to be aware of nonsexually transmitted syphilis, acquired in daily life by children without a history of sexual contact.

Red blood cell distribution width to platelet ratio in neonatal foals with sepsis

BACKGROUND

Rapid and accurate markers to aid diagnosis of sepsis are needed in neonatal foals. The CBC variable red blood cell distribution width (RDW) to platelet ratio (RPR) is associated with inflammatory response and linked to poor outcomes of sepsis in human patients.

HYPOTHESIS

Explore the correlation of RPR with sepsis in neonatal foals and evaluate RPR predictive and prognostic value.

ANIMALS

Three hundred seventeen hospitalized neonatal foals ≤7 days of age that had a CBC and physical exam performed at admission between 2012 and 2021.

METHODS

Retrospective case-control study. Clinical records were used to calculate sepsis scores and define groups. Red blood cell distribution width to platelet ratio was calculated and compared between groups (septic vs nonseptic) based on Kruskal-Wallis and Wilcoxon signed-rank tests. A multivariate logistic regression model to predict sepsis was created. The cutoff for RPR was obtained based on the maximal Youden Index. The Kaplan-Meier method and the log-rank test were used to estimate survival curves and compare survival rates based on RPR.

RESULTS

Red blood cell distribution width to platelet ratio was significantly higher in septic foals (Median = 0.099, confidence interval [CI] [0.093; 0.108]) than in sick nonseptic (0.085, CI [0.083; 0.089]) and healthy foals (0.081, CI [0.077; 0.086]; P < .0001). Red blood cell distribution width to platelet ratio was able to predict sepsis with high accuracy (AUC = 82.1%). The optimal RPR cutoff for sepsis was 0.09.

CONCLUSIONS AND CLINICAL IMPORTANCE

Red blood cell distribution width to platelet ratio calculation is practical, inexpensive, and based on CBC-derived data. Calculation of RPR along with CBC can aid in the diagnosis of sepsis and estimation of outcome.

High red cell distribution width-to-platelet ratio indicates adverse outcomes for hepatitis B virus-associated decompensated cirrhosis

Background: This work was designed to determine the association between red cell distribution width-to-platelet ratio (RPR) and 30-day prognosis in hepatitis B virus-associated decompensated cirrhosis (HBV-DC) patients. Methods: A total of 168 HBV-DC patients were included. Independent risk factors for poor prognosis were determined by logistic regression analyses. Results: A total of 21 (12.5%) patients died within 30 days. RPR was higher in nonsurvivors than in survivors. Multivariate analysis identified RPR and Model for End-Stage Liver Disease (MELD) score as independent prognostic predictors, and the predictive value of RPR was similar to that of the MELD score. Moreover, combining RPR with the MELD score further improved the predictive value for mortality. Conclusion: RPR has potential as a reliable tool for the prediction of poor prognosis in HBV-DC patients.

Treponema pallidum infection rate in patients attending the general hospital of Benguela, Angola

INTRODUCTION

The objectives of this study were to estimate the rate of infection by Treponema pallidum and co-infection with Human Immunodeficiency Virus (HIV) in individuals attending the General Hospital of Benguela (GHB), Angola, to verify the Rapid Plasma Reagin (RPR) test performance for its diagnosis when compared with other RPR tests, and to compare a rapid treponemal test with the Treponema pallidum hemagglutination assay (TPHA).

METHODOLOGY

This is a cross-sectional study carried out between August 2016 and January 2017, at the GHB, 546 individuals attending the emergency room, the outpatient service or hospitalized at the GHB were included. All the samples were tested at the GHB with the routine hospital RPR test and a rapid treponemal test. The samples were then transported to the Institute of Hygiene and Tropical Medicine (IHMT) where RPR testing and TPHA testing were performed.

RESULTS

The rate of T. pallidum active infection, demonstrated by a reactive RPR and TPHA result, was 2.9%, of which 81.2% corresponded to indeterminate latent syphilis and 18.8% to secondary syphilis. HIV co-infection was detected in 62.5% of individuals diagnosed with syphilis. Past infection, defined as a non-reactive RPR and reactive TPHA test, was diagnosed in 4.1% of individuals.

CONCLUSIONS

The high rate of syphilis/HIV co-infection emphasizes the urgent requirement for adequate sexually transmitted infections (STIs) screening, prevention and treatment programs. In addition, implementation of quality control measures within RPR testing protocols at GHB are needed, including training for laboratory personnel, adequate equipment and introduction of other rapid testing.

Protamine-derived peptide RPR (Arg-Pro-Arg) ameliorates oleic acid-induced lipogenesis via the PepT1 pathway in HepG2 cells

The protamine-derived peptide arginine-proline-arginine (RPR) can ameliorate lifestyle-related diseases such as obesity and hypercholesterolemia. Thus, we hypothesized that the hypolipidemic activity of RPR could attenuate events leading to non-alcoholic fatty liver disease. Addition of 2 m m oleic acid (OA) to the culture medium induced fatty liver conditions in HepG2 cells. The OA + RPR group showed significantly decreased cellular or medium triglyceride (TG) level compared with the OA group. Stearoyl-CoA desaturase-1 (SCD1) or sterol regulatory element-binding protein 1 (SREBP1) protein level was significantly lower in the OA + RPR group than in the OA group. In the R + P + R amino acid mixture-treated group, the TG level was not significantly different from that in the OA-treated group. The OA + RP- or OA + PR-treated groups showed significantly decreased cellular TG level compared with the OA group. Moreover, the effect of RPR disappeared when the peptide transporter 1 (PepT1) was knocked down with a siRNA. Collectively, our results demonstrated that RPR effectively ameliorated hepatic steatosis in HepG2 cells via the PepT1 pathway.

COVID-19 mRNA Vaccines May Cause False Reactivity in Some Serologic Laboratory Tests, Including Rapid Plasma Reagin Tests

OBJECTIVES

Acute viral infections and some vaccines have been shown to increase false positivity in serologic assays. We assessed if the messenger RNA coronavirus disease 2019 (COVID-19) vaccines could cause false reactivity in common serologic assays in a pilot longitudinal cohort.

METHODS

Thirty-eight participants with sera available prevaccination, 2 weeks after each vaccine dose, and monthly thereafter for up to 5 months were tested for common infectious disease serologies and antiphospholipid syndrome (APS) serology markers on the BioPlex 2200, Sure-Vue rapid plasma reagin (RPR), and Macro-Vue RPR. Twenty-two participants received the Moderna vaccine and 16 received the Pfizer vaccine.

RESULTS

Most assays had no change in reactivity over the course of the sample draws, including APS markers. Epstein-Barr virus immunoglobulin G (IgG), measles IgG, and rubella immunoglobulin M all had possible false reactivity in one to two participants. RPR tests demonstrated false reactivity, with baseline nonreactive participant samples becoming reactive following vaccination. There were more false reactive participants (7/38) in the BioPlex RPR than in the Sure-Vue (2/38) and Macro-Vue (1/38) tests. All falsely reactive RPR tests were in participants who received the Moderna vaccine.

CONCLUSIONS

Serologic assays with results that do not fit the clinical picture following COVID-19 vaccination should be repeated. Effects of false reactivity can last more than 5 months in some assays. In particular, RPR is susceptible to false reactivity, and there is variability among assays. Larger longitudinal studies are needed to determine the incidence and window of false reactivity.

Characterization and Fine Mapping of qRPR1-3 and qRPR3-1, Two Major QTLs for Rind Penetrometer Resistance in Maize

Stalk strength is one of the most important traits in maize, which affects stalk lodging resistance and, consequently, maize harvestable yield. Rind penetrometer resistance (RPR) as an effective and reliable measurement for evaluating maize stalk strength is positively correlated with stalk lodging resistance. In this study, one F₂ and three F_2:3 populations derived from the cross of inbred lines 3705I (the low RPR line) and LH277 (the high RPR line) were constructed for mapping quantitative trait loci (QTL), conferring RPR in maize. Fourteen RPR QTLs were identified in four environments and explained the phenotypic variation of RPR from 4.14 to 15.89%. By using a sequential fine-mapping strategy based on the progeny test, two major QTLs, qRPR1-3 and qRPR3-1, were narrowed down to 4-Mb and 550-kb genomic interval, respectively. The quantitative real-time PCR (qRT-PCR) assay was adopted to identify 12 candidate genes responsible for QTL qRPR3-1. These findings should facilitate the identification of the polymorphism loci underlying QTL qRPR3-1 and molecular breeding for RPR in maize.

Genetic Architecture of Maize Rind Strength Revealed by the Analysis of Divergently Selected Populations

The strength of the stalk rind, measured as rind penetrometer resistance (RPR), is an important contributor to stalk lodging resistance. To enhance the genetic architecture of RPR, we combined selection mapping on populations developed by 15 cycles of divergent selection for high and low RPR with time-course transcriptomic and metabolic analyses of the stalks. Divergent selection significantly altered allele frequencies of 3,656 and 3,412 single- nucleotide polymorphisms (SNPs) in the high and low RPR populations, respectively. Surprisingly, only 110 (1.56%) SNPs under selection were common in both populations, while the majority (98.4%) were unique to each population. This result indicated that high and low RPR phenotypes are produced by biologically distinct mechanisms. Remarkably, regions harboring lignin and polysaccharide genes were preferentially selected in high and low RPR populations, respectively. The preferential selection was manifested as higher lignification and increased saccharification of the high and low RPR stalks, respectively. The evolution of distinct gene classes according to the direction of selection was unexpected in the context of parallel evolution and demonstrated that selection for a trait, albeit in different directions, does not necessarily act on the same genes. Tricin, a grass-specific monolignol that initiates the incorporation of lignin in the cell walls, emerged as a key determinant of RPR. Integration of selection mapping and transcriptomic analyses with published genetic studies of RPR identified several candidate genes including ZmMYB31, ZmNAC25, ZmMADS1, ZmEXPA2, ZmIAA41 and hk5. These findings provide a foundation for an enhanced understanding of RPR and the improvement of stalk lodging resistance.

Anti-Obesity and Hypocholesterolemic Actions of Protamine-Derived Peptide RPR (Arg-Pro-Arg) and Protamine in High-Fat Diet-Induced C57BL/6J Mice

Dietary protamine can ameliorate hyperlipidemia; however, the protamine-derived active peptide and its hypolipidemic mechanism of action are unclear. Here, we report the discovery of a novel anti-obesity and hypocholesterolemic peptide, RPR (Arg-Pro-Arg), derived from protamine in mice fed a high-fat diet for 50 days. Serum cholesterol levels were significantly lower in the protamine and RPR groups than in the control group. White adipose tissue weight was significantly decreased in the protamine and RPR groups. The fecal excretion of cholesterol and bile acid was significantly higher in the protamine and RPR groups than in the control group. We also observed a significant decrease in the expression of hepatic SCD1, SREBP1, and adipocyte FAS mRNA, and significantly increased expression of hepatic PPARα and adipocyte PPARγ1 mRNA in the protamine group. These findings demonstrate that the anti-obesity effects of protamine are linked to the upregulation of adipocyte PPARγ1 and hepatic PPARα and the downregulation of hepatic SCD1 via SREBP1 and adipocyte FAS. RPR derived from protamine has a crucial role in the anti-obesity action of protamine by evaluating the effective dose of adipose tissue weight loss.

Evaluation of red cell distribution width to platelet ratio as a novel non-invasive index for predicting hepatic fibrosis in patients with chronic hepatitis C

BACKGROUND AND STUDY AIMS

Assessing the extent of fibrosis is an essential part of therapeutic decisions in patients with chronic hepatitis C (CHC). Liver biopsies are the "gold standard" for evaluating liver fibrosis but have many limitations. Thus, noninvasive predictors of fibrosis have been developed. This study aimed to determine the effectiveness of red cell distribution width (RDW) to platelet ratio as a simple noninvasive method for predicting the hepatic fibrosis stage in patients with CHC.

PATIENTS AND METHODS

This cross-sectional study included 197 Egyptian patients with CHC. A routine pretreatment reference needle liver biopsy was performed. Fib-4, transient elastography (TE) by Fibroscan, AST to Platelet Ratio Index (APRI), and RDW to platelet ratio (RPR) were measured. Predictors of significant fibrosis (Metavir score ≥ F2) and advanced fibrosis (Metavir score ≥ F3) were identified.

RESULTS

Fib-4, TE, APRI, and RPR values differed significantly when comparing different stages of fibrosis (p < 0.01). Fib-4, TE, APRI, and RPR were reliable diagnostic tools at cutoff values of 1.17, 7.75, 0.18, and 0.07, respectively, for predicting significant fibrosis and cutoff values of 1.99, 8, 1.77, and 0.08, respectively, for predicting advanced fibrosis. Using logistic regression analysis, TE was identified as an independent predictor associated with significant and advanced fibrosis. Fib-4 was significantly associated with advanced fibrosis only.

CONCLUSION

The use of Fib-4, TE, APRI, and RPR measurements may decrease the need for liver biopsies for predicting significant and advanced fibrosis. RPR showed fair sensitivity, specificity, positive and negative predictive values, and overall accuracy for predicting significant fibrosis in patients with CHC.

Evaluation of the fully automated AIX1000 rapid plasma reagin system compared to a manual plasma reagin testing method for the diagnosis of syphilis

The analytical performance of the FDA-cleared AIX1000 automated RPR testing platform was evaluated in comparison to manual RPR card testing. Eight hundred thirty-three patient serum samples were analyzed, 87 samples were positive by the AIX1000, 108 were positive by the manual test method; overall agreement between methods was 96.5% (κ = 0.83). Cases were further classified by clinical and laboratory-based confirmation of disease, to which reactivity rates were compared, yielding sensitivities of 96.4% and 100%, and specificities of 99.2% and 96.8% for the automated and manual RPR methods, respectively. The difference in specificity between methods was statistically significant (P < 0.001). Twenty-five of 29 samples with discordant results were reactive by manual testing (titers of 1:1 or 1:2); 21 of 25 patients with negative AIX100 results were identified to have histories of remote, treated syphilis. Overall, the AIX1000 platform demonstrated excellent agreement with the manual RPR method; discrepancies occurred with specimens at the threshold of reactivity.

Anatomical and biochemical evidence for Treponema pallidum in a 19th to early twentieth century skeletal cadaver

This report summarizes findings relating to the biochemical and skeletal evidence for Treponema pallidum in an unusually old case of congenital syphilis. In 1951, the Milwaukee Public Museum acquired skeletal remains from the Surgical School of Marquette University. The male was identified as a 60-65-year-old, that was suffering from congenital syphilis. His remains are now part of the anthropological collections of Wisconsin Lutheran College (Milwaukee, Wisconsin). Venereal Disease Research Laboratory (VDRL) and Rapid Plasma Reagin (RPR) tests were used to verify the presence of the bacteria-generated antibodies, while mass spectrometry testing provided indirect evidence for the historical treatment of the disease. Notably, antibody detection in human remains of this age is rare. These initial results support what is known of syphilis and its treatment prior to the wide scale, clinical use of penicillin therapy, and describe evidence for long-term skeletal symptoms of congenital syphilis in century-old human remains.

A clinical audit of maternal syphilis in a regional hospital in KwaZulu-Natal, South Africa

Background

Despite the availability of screening guidelines and effective treatment for maternal syphilis (MS), its prevalence remains high and is re-emerging in many parts of the world. This might be because of varying screening tests and algorithms for the laboratory diagnosis and treatment of syphilis. In addition, HIV co-infection may compromise the elimination of MS. The present study is a clinical audit of the prevalence of MS in KwaZulu-Natal, South Africa, using the 'Traditional Algorithm' screening.

Methods

This was a retrospective audit in which data on syphilis testing were obtained over a 1-year period (2016) at a large regional hospital in South Africa. The standard screening test at the study site was the non-treponemal antigen, rapid plasma reagin (RPR). Data on the prevalence of MS and comorbidity with HIV infection were analysed.

Results

There were 10 680 deliveries in the study period of which 118 were RPR reactive, giving an MS prevalence of 1.1%. MS occurred predominantly in the age groups < 18 and > 35 years (p = 0.001). The prevalence of HIV infection was 41.2% (n = 4451). Seventy-two (61.0%) had both HIV and MS infection, whilst 46 (39.0%) had discordant results (p = 0.001).

Conclusion

We report an increase in the prevalence of MS compared to previous South African National Antenatal Syphilis Surveillance studies. This may be because of the prozone effect caused by HIV infection on the sensitivity of the RPR. We propose a change in MS screening, using a Rapid DUO (Dual HIV and syphilis point of care test) and Reverse Algorithm for screening that could improve the sensitivity, detection and management of both diseases.

Degradation of carbendazim in water via photo-Fenton in Raceway Pond Reactor: assessment of acute toxicity and transformation products

This study aimed at investigating the degradation of fungicide carbendazim (CBZ) via photo-Fenton reactions in artificially and solar irradiated photoreactors at laboratory scale and in a semi-pilot scale Raceway Pond Reactor (RPR), respectively. Acute toxicity was monitored by assessing the sensibility of bioluminescent bacteria (Aliivibrio fischeri) to samples taken during reactions. In addition, by-products formed during solar photo-Fenton were identified by liquid chromatography coupled to mass spectrometry (UFLC-MS). For tests performed in lab-scale, two artificial irradiation sources were compared (UV_{λ > 254nm} and UV-Vis_{λ > 320nm}). A complete design of experiments was performed in the semi-pilot scale RPR in order to optimize reaction conditions (Fe²⁺ and H₂O₂ concentrations, and water depth). Efficient degradation of carbendazim (> 96%) and toxicity removal were achieved via artificially irradiated photo-Fenton under both irradiation sources. Control experiments (UV photolysis and UV-Vis peroxidation) were also efficient but led to increased acute toxicity. In addition, H₂O₂/UV_{λ > 254nm} required longer reaction time (60 minutes) when compared to the photo-Fenton process (less than 1 min). While Fenton's reagent achieved high CBZ and acute toxicity removal, its efficiency demands higher concentration of reagents in comparison to irradiated processes. Solar photo-Fenton removed carbendazim within 15 min of reaction (96%, 0.75 kJ L^-1), and monocarbomethoxyguanidine, benzimidazole isocyanate, and 2-aminobenzimidazole were identified as transformation products. Results suggest that both solar photo-Fenton and artificially irradiated systems are promising routes for carbendazim degradation.

Clinical Performance of the BioPlex 2200 Syphilis Total & RPR Assay at a Tertiary Medical Center with a High Rate of Syphilis

Manual treponemal and nontreponemal serologic testing has historically been used for the diagnosis of syphilis. This approach is simple and reproducible but labor intensive. Recently, the FDA cleared the fully automated BioPlex 2200 Syphilis Total & RPR assay for the detection of treponemal and nontreponemal antibodies. We evaluated the clinical performance of this assay at a tertiary medical center with a high syphilis prevalence. Prospective consecutively collected (n = 400) and known RPR-positive (n = 100) specimens were compared using predicate manual rapid plasma reagin (RPR) and fluorescent treponemal antibody absorption (FTA) methods and the BioPlex 2200 Syphilis Total & RPR assay. Positive and negative percent agreements (PPA and NPA, respectively) between the assays were calculated. The PPA and NPA between the manual and BioPlex 2200 RPR results for the prospective population were 85% (17/20; 95% confidence interval [CI], 69% to 100%) and 98% (373/380; 95% CI, 97% to 99%), respectively. The PPA for the manual RPR-positive population was 88% (88/100; 95% CI, 82% to 94%). Overall, the manual and BioPlex 2200 RPR titers demonstrated 78% (99/127) concordance within ±1 dilution and 94% (120/127) within ±2 dilutions. An interpretation of the syphilis serologic profile using the traditional algorithm showed a concordance of 99.5% in the prospective population and 85% in the manual RPR-positive cohort. The performance of the BioPlex 2200 Syphilis Total & RPR assay is comparable to those of manual methods. The high NPA of this assay combined with the ability to automate a historically labor-intensive assay is an appealing attribute for syphilis screening in a high-volume laboratory.

Predictive value of the red blood cell distribution width-to-platelet ratio for hepatic fibrosis

AIMS

The red blood cell distribution width-to-platelet ratio (RPR) has been reported to be an indicator of hepatic fibrosis in patients with chronic hepatitis B (HBV), nonalcoholic fatty liver disease (NAFLD) or chronic hepatitis C (HCV). However, no research has explored the RPR in all patients with hepatic fibrosis. There is a recognized need to establish whether the RPR could assess hepatic fibrosis and reflect the severity of fibrosis, regardless of the patient's etiology.

METHODS

Quantitative data from 1282 patients who underwent liver biopsy between January 2010 and December 2014 at the Second Affiliated Hospital of Zhejiang University School of Medicine were included. The etiologies included HBV or HCV infection, NAFLD, schistosomiasis, granulomatous liver disease, and vascular abnormalities. Five noninvasive models were calculated for all patients based on laboratory parameters. The degrees of fibrosis severity were evaluated based on the Metavir scoring scale.

RESULTS

The RPR demonstrated the best accuracy of predicting hepatic fibrosis among the selected five models (0.75, p < .001) regardless of etiology. In addition, the RPR values increased with advanced hepatic fibrosis progression. Furthermore, combining the RPR with the white blood cell (WBC) count improved the accuracy of grading hepatic fibrosis as reflected by the likelihood ratio (LR + 9.03, LR - 0.49).

CONCLUSION

The RPR is a useful indicator for hepatic fibrosis, regardless of etiology, and can reflect the severity of fibrosis. This study supports further clinical development of the RPR both in a stepwise manner or in combination with inflammatory parameters to improve the accuracy of scoring hepatic fibrosis.

Data on the generation of rabbit infections and RPR titre changes in serum samples from syphilis patients at follow-up

The data presented in this article are related to the research article entitled “Performance of novel infection phase-dependent antigens in syphilis serodiagnosis and treatment efficacy determination”. The rabbit model [1], [2] is an appropriate animal model for studying syphilis, a classic sexually transmitted disease (STD). Live Treponema pallidum (T. pallidum, Tp) and inactivated T. pallidum were inoculated in the backs of New Zealand rabbits. RT-PCR was performed to determine whether T. pallidum DNA could be detected in different groups. Sixty paired serum samples from patients at follow-up were tested by RPR and recombinant Tp0971-, Tp0768-, Tp0462- and Tp92-based ELISA.

Comparison of Manual and Fully Automated AIX1000 Rapid Plasma Reagin Assays for Laboratory Diagnosis of Syphilis

The analytical performance of the AIX1000 system, a fully automated and recently FDA-cleared rapid plasma reagin (RPR) system, was evaluated by comparison to a manual RPR test in a traditional syphilis testing algorithm. A total of 1,028 consecutive serum samples submitted for syphilis testing to the University of North Carolina Hospitals Clinical Immunology Laboratory were tested per each manufacturer's instructions. Among those samples, 996 were nonreactive and 20 were reactive using both the ASI RPR card system and the AIX1000 system. Of the 12 discrepant specimens, 11 were AIX1000 reactive and ASI card nonreactive whereas 1 specimen was ASI card reactive and AIX1000 nonreactive. The sensitivity and specificity of the manual ASI card were 76.0% and 99.8%, respectively, while the sensitivity and specificity of the AIX100 were 100.0% and 99.4%, respectively (sensitivity P = 0.03). Among the 20 concordant reactive specimens, 68.4% of the titers agreed within ±1 dilution between methods. Reproducibility testing of the AIX1000 system demonstrated qualitative and semiquantitative (within ±1 dilution) agreement between specimens tested on different days of 96.0% and 76.0%, respectively, and 100.0% agreement between replicates within the same run. One of 24 samples analyzed under other disease conditions was reactive on both the AIX1000 system and the ASI card. Overall, the fully automated AIX1000 system demonstrated significantly enhanced sensitivity and specificity similar to that of the manual ASI RPR card test, making the AIX1000 system suitable for the laboratory diagnosis of syphilis in a clinical laboratory setting.

Response surface methodology modeling to improve degradation of Chlorpyrifos in agriculture runoff using TiO2 solar photocatalytic in a raceway pond reactor

This paper deals with the use of a raceway pond reactor (RPR) as an alternative photoreactor for solar photocatalytic applications. Raceway pond reactors are common low-cost reactors which can treat large volumes of water. The experiments were carried out with TiO₂ in the agriculture effluent spiked with Chlorpyrifos (CPF) at circumneutral pH. The Response Surface Methodology (RSM) was used to find the optimum process parameters to maximize CPF oxidation from the mathematical model equations developed in this study using R software. By ANOVA, p-value of lack of fit > 0.05 indicated that, the equation was well-fitted. The theoretical efficiency of CPF removal, under the optimum oxidation conditions with UV solar energy of around 697 ± 5.33 lux, was 84.01%, which is in close agreement with the mean experimental value (80 ± 1.42%) confirming that the response model was suitable for the optimization. As far as the authors know, this is the first study of CPF removal using RPR in agriculture runoff at circumneutral pH.

A retrospective study on rapid plasma reagin testing in patients with Pityriasis rosea

Pityriasis rosea (PR) is an acute self-limited exanthem characterized by oval erythematous patches with scale and may be difficult to differentiate from secondary syphilis. A rapid plasma reagin (RPR) test can be used to rule in secondary syphilis with high sensitivity and specificity. A retrospective study was performed on patients at Weill Cornell Medicine, who were diagnosed with PR from 2000 to 2016 and also received RPR testing at the time of diagnosis. The objective was to assess the frequency of secondary syphilis when the initial clinical impression was PR. Only 2/142 patients (1.4%) had a reactive RPR test. Based on our results, we advocate that careful social and sexual histories be taken in all patients presenting with atypical PR and syphilis screening performed if risk factors are present.

Performance Characteristics of the Reverse Syphilis Screening Algorithm in a Population With a Moderately High Prevalence of Syphilis

OBJECTIVES

With the recent introduction of automated treponemal tests, a new reverse syphilis algorithm has been proposed and now used by many clinical laboratories. We analyzed the impact of instituting the reverse screening syphilis algorithm in a laboratory that serves a geographic area with a moderately high prevalence of syphilis infection.

METHODS

Serum samples sent for syphilis testing were tested using a treponemal enzyme immunoassay (EIA) as the screening assay. EIA reactive samples were tested by rapid plasma reagin (RPR) and titered to end point if reactive. RPR nonreactive samples were analyzed by the Treponema pallidum particle agglutination test (TP-PA). Pertinent medical records were reviewed for false-reactive screens and samples with evidence of past syphilis infection.

RESULTS

Among 10,060 patients tested, 502 (5%) were reactive on the initial EIA screen. The RPR was reactive in 150 (1.5%). TP-PA testing determined that 103 (1.0%) were falsely reactive on initial EIA screen. The reverse screening algorithm, however, identified 242 (2.4%) with evidence of latent, secondary, or past syphilis, 21 of whom had no or unknown prior treatment with antibiotics.

CONCLUSIONS

Despite a 1.0% false-reactive rate, the reverse syphilis algorithm detected 21 patients with possible latent syphilis that may have gone undetected by traditional syphilis screening.

Clinical and neuropsychological characteristics of general paresis misdiagnosed as primary psychiatric disease

BACKGROUND

Neurosyphilis is caused by the invasion of Treponema pallidum into the central nervous system. General paresis (GP) is a type of neurosyphilis. The main manifestation of general paresis is dementia; however, this is different from the other types of dementia, which can be cured by adequate doses of penicillin in the early stage. Neurosyphilis is the "great imitator" because it can mimic many types of medical disorders. In addition, the manifestations of neurosyphilis are not typical. Psychiatric disorders as a cause of general paresis have become more common due to the use of antibiotics. Patients with a psychiatric manifestation are often misdiagnosed. The purpose of this study was to explore the differences in the clinical and neuropsychological characteristics of general paresis between patients misdiagnosed as having a primary psychiatric disease and patients diagnosed correctly upon seeing a doctor. The results may assist clinicians in the early identification of neurosyphilis with a mental disorder.

METHOD

The demographic and clinical manifestations, laboratory tests, and neuroimaging and neuropsychological characteristics were analysed in 55 general paresis patients with psychiatric disorders, including 29 patients misdiagnosed as primary psychiatric disease and 26 patients diagnosed as having general paresis after being seen once by a doctor.

RESULT

All of the patients had positive assay results for cerebral spinal fluid (CSF) Treponema pallidum hemagglutination (TPHA). Only 43.3 % of misdiagnosed patients and 30.8 % of general paresis patients had positive results for the CSF rapid plasma reagin (RPR) test; 96.4 % patients had abnormal neuroimaging. Mood disturbances were the most common psychiatric disorder in the general paresis patients, especially agitation, between the two groups (patients with general paresis who were misdiagnosed as having primary psychiatric disease and patients who had never been misdiagnosed) (p = 0.011).

CONCLUSION

Our findings reinforce the importance of performing serologic testing for syphilis. This should be a part of the evaluation of patients with psychiatric disorders, especially patients with cognitive impairment. When the syphilis serology is positive, the patient should be examined thoroughly for neurosyphilis by lumbar puncture. Brain imaging could also aid the physician in discriminating these patients from those with a functional mental disorder.

A study on usefulness of a set of known risk factors in predicting maternal syphilis infections in three districts of Western Province, Zambia

Introduction

Despite roll-out of cost-effective point-of-care tests, less than half antenatal attendees in rural western Zambia are screened for syphilis. This study formulated a clinical, risk-based assessment criteria and evaluated its usefulness as a non-biomedical alternative for identifying high-risk prenatal cases.

Methods

We conducted a cross-sectional survey of antenatal clinic attendees in Kaoma, Luampa and Nkeyema districts to collect data on exposure to nine pre-selected syphilis risk factors. These factors were classified into major and minor factors based on their observed pre-study association strengths to maternal syphilis. Clinical disease was defined as exposure to either two major factors, one major with two minor factors or three minor factors. Sensitivity, specificity and predictive values of the clinical protocol were then calculated in comparison to rapid plasmin reagin results.

Results

The observed syphilis prevalence was 9.3% (95% CI: 7.4 - 11.6%) and the overall sensitivity of the study criteria was 62.3% with positive predictive value of 72.9%. Sensitivities of individual case-defining categories were even lower; from 17.4% to 33.3%. Results confirmed that abortion history, still birth, multiple sexual partners, previous maternal syphilis infection, partner history of sexually transmitted infection and maternal co-morbid conditions of HIV and genital ulcer disease were significantly associated to maternal syphilis in study population as well.

Conclusion

The criteria was not as effective as biomedical tests in identifying maternal syphilis. However, it could be a useful adjunct/alternative in antenatal clinics when biomedical tests are either inadequate or unavailable.

Neurosyphilis in psychiatric practice: a case-based discussion of clinical evaluation and diagnosis

OBJECTIVE

Neurosyphilis can present with a wide range of neuropsychiatric symptoms. Hence, psychiatrists need to be familiar with tests for syphilis screening and how to interpret syphilis serologic tests.

METHODS

We present four cases of patients with positive syphilis tests encountered in a psychiatric hospital.

RESULTS

Two cases were treated for neurosyphilis, while the other two cases did not have active syphilis infection despite positive results.

CONCLUSION

We thus highlight the challenges encountered by psychiatrists in screening for and diagnosing cases of neurosyphilis.

Treponemal antibody in CSF and cellular immunity in peripheral blood of syphilitic patients with persisting positive rapid plasma regain

The ratio of patients with RPR constant positive more than 2 years despite receiving standard syphilis treatment has been reported to be 11.54%~31.3%. The current interpretations on this phenomenon are cellular immune function restrained and the existence of neurosyphilis or asymptomatic neurosyphilis. We conducted this study to detect the treponemal antibody in cerebrospinal fluid (CSF) and lymphocyte subsets in peripheral blood of syphilis patients with persisting RPR positive more than 2 years without neurologic signs, and then explore their relationship. In this study, Treponemal antibody in CSF of 46 syphilitic with HIV negative were measured by syphilis serum test and compared with that of 5 neurosyphilis. Lymphocyte subsets were measured by flow cytometry (FCM) and compared with that of 30 healthy controls. We observed that treponemal antibody in CSF was detected not only in 12 cases (25.21%) of 46 treated patients, but also in 5 neurosyphilis. The ratio of lymphocyte subsets revealed that CD3+, CD4+ T cells and natural killer (NK) cells showed no significant differences between the patient and healthy controls (P>0.05), while CD8+ T cells in patients were significant higher than that in healthy controls (P<0.001). Lymphocyte subsets showed no significant differences between the patients with treponemal antibody positive and negative in CSF (P>0.05). In conclusion, the treponemal antibody in CSF of treated patients suggests that part of them were asymptomatic neurosyphilis and with cellular immunodifeciency. And there is no significant relationship between asymptomatic neurosyphilis and cellular immunodeficiency in peripheral blood.

Canadian Public Health Laboratory Network laboratory guidelines for the use of serological tests (excluding point-of-care tests) for the diagnosis of syphilis in Canada

Syphilis, caused by the bacterium Treponema pallidum subsp. pallidum, is an infection recognized since antiquity. It was first reported at the end of the 15th century in Europe. Infections may be sexually transmitted as well as spread from an infected mother to her fetus or through blood transfusions. The laboratory diagnosis of syphilis infection is complex. Because this organism cannot be cultured, serology is used as the principal diagnostic method. Some of the issues related to serological diagnoses are that antibodies take time to appear after infection, and serology screening tests require several secondary confirmatory tests that can produce complex results needing interpretation by experts in the field. Traditionally, syphilis screening was performed using either rapid plasma reagin or Venereal Disease Research Laboratory tests, and confirmed by treponemal tests such as MHA-TP, TPPA or FTA-Abs. Currently, that trend is reversed, ie, most of the laboratories in Canada now screen for syphilis using treponemal enzyme immunoassays and confirm the status of infection using rapid plasma reagin or Venereal Disease Research Laboratory tests; this approach is often referred to as the reverse algorithm. This chapter reviews guidelines for specimen types and sample collection, treponemal and non-treponemal tests utilized in Canada, the current status of serological tests for syphilis in Canada, the complexity of serological diagnosis of syphilis infection and serological testing algorithms. Both traditional and reverse sequence algorithms are recommended and the algorithm used should be based on a combination of local disease epidemiology, test volumes, performance of the proposed assays and available resources.

No improvement in serological response among serofast latent patients retreated with benzathine penicillin

Persistent non-treponemal titres after treatment are common among patients with latent syphilis. Although retreatment is often done in clinical practice, optimal management remains uncertain due to the paucity of data regarding serological response to retreatment and long-term outcomes. We compared the serological responses of serofast latent syphilis patients retreated with 7.2 million units of benzathine penicillin with the responses of patients who did not receive retreatment (control group). We retrospectively analysed the serological response to therapy following retreatment of 35 serofast latent syphilis patients at 12 months with benzathine penicillin 2.4 million units weekly for 3 weeks. In all, 74.3% (26/35) of the cases with latent syphilis who failed to achieve serological cure at 12 months after initial therapy achieved serological cure after retreatment and after an additional 12 months of follow-up. However, statistically similar serological cure rate was observed in 80.0% (28/35) of the control group (p > .05). Our findings illustrate no improvement in serological response among serofast latent patients retreated with three doses of benzathine penicillin.

Importance of extending the use of polymerase chain reaction in the diagnosis of venereal syphilis in a blood transfusion center in Burkina Faso, West Africa

Introduction

Due to the existence of a variety of types of non-venereal syphilis caused by the related T. pallidum, regular serological testing such as Rapid Plasma Reagin (RPR) and Chemiluminescent Microparticle Immunoassay Technique (CMIA) are often unable to differentiate venereal syphilis from the non- venereal one, hence, the interest in the use of molecular biology testing for a confirmation diagnosis of syphilis caused by Treponema pallidum subspecies pallidum.

Objective

The study is designed to assess the effectiveness of PCR testing and serological methods in the diagnosis of Treponema pallidum subsp pallidum among blood donors in Burkina Faso.

Methodes

The study included 6375 samples of volunteer blood donors from the regional blood transfusion center of Ouagadougou (CRTS/O). Among samples, 183 positive and 59 negative in RPR were analyzed to detect antibodies anti-T. pallidum subsp pallidum with a immunoassay method (CMIA) and were confirmed using the Polymerase Chain Reaction testing.

Results

In RPR, we obtained a prevalence rate of 2.9% (183/6375) for treponematosis. From the 183 RPR+ specimen, 108 (59%) were found CMIA+ and 11 (6%) were confirmed PCR+. While the 59 pattern RPR-; 31 (52.5%) were CMIA + including 3 (5.1%) tested PCR+. Seventy-five (75) samples RPR + /CMIA-; 2 (2.7%) were confirmed positive by PCR. All 28 samples RPR-/CMIA- were confirmed negative by PCR.

Conclusion

PCR testing confirmed a low distribution of T. pallidum subsp pallidum in comparison to serological methods. Cross-reactions, existence of non-venereal treponemal or immunological scars could account for the discrepancy between the results obtained.

Comparison of a combined nontreponemal (VDRL) and treponemal immunoblot to traditional nontreponemal and treponemal assays

BACKGROUND

Serology is the mainstay for the diagnosis and management of patients with syphilis. Newer technologies such as immunoblotting are now available for the diagnosis of syphilis.

METHODS

A commercial IgM/IgG immunoblot assay that detects both nontreponemal (VDRL-Venereal Disease Research Laboratory) and treponemal antibodies was compared with standard nontreponemal and treponemal assays. The immunoblot and T. pallidum particle agglutination assay (TP-PA) were performed on 198 samples. Ninety-seven samples were Rapid plasma reagin (RPR)-positive and one hundred one were RPR-negative. Positive RPR samples were titered by VDRL.

RESULTS

The agreement, sensitivity, and specificity of the IgM/IgG VDRL results of the immunoblot compared to RPR were 74.2% (95% CI: 67.2-80.2), 77.3% (95% CI: 70.2-83.4), and 71.3% (95% CI: 64.4-77.1), respectively. The agreement, sensitivity, and specificity of the IgM/IgG treponemal immunoblot compared to TP-PA were 100% for all parameters, if the ten equivocal results were not used in the calculation.

CONCLUSION

The treponemal portion of the ViraBlot IgM/IgG immunoblot compared well with the treponemal confirmation assay and could be a useful supplemental method to fluorescent treponemal antibody or TP-PA for the confirmation of syphilis. The addition of the detection of nontreponemal antibodies to the immunoblot assay, however, may not be of added benefit to the overall assay, due to decreased sensitivity and specificity compared to standard assays.

Comparing the performance of traditional non-treponemal tests on syphilis and non-syphilis serum samples

The goal of the present study was to determine the performance of two traditional non-treponemal tests for syphilis. Syphilis sera (n = 209) included different stages of disease, and control sera (n = 247) were from patients with tumours, leprosy, systemic lupus erythematosus, hepatitis, pregnant women and healthy individuals. Treponema pallidum ELISA, Treponema pallidum particle agglutination and rapid treponema-specific tests were used as gold standards. Rapid plasma reagin or toluidine red unheated serum test had a sensitivity and specificity of over 95%. False-negative reactions of rapid plasma reagin and toluidine red unheated serum test were observed mainly in primary and latent syphilis cases, and false-positive reactions were present in systemic lupus erythematosus, hepatitis-infected patients. Overall, both non-treponemal tests had high sensitivities and specificities making the assays attractive as screening tests for syphilis. When examined on WHO reference serum samples and based on lower limits of detection, non-treponemal tests were less sensitive than treponema-specific tests.

The importance of IgM positivity in laboratory diagnosis of gestational and congenital syphilis

From January 1, 2009 through December 31, 2011, from 33,753 blood samples for syphilis screening, Treponema pallidum infections were confirmed in 241 pregnant women at the Department of Dermatology, Venerology, and Dermatooncology of Semmelweis University Budapest. In this period, four children born to inadequately or untreated women were confirmed to have connatal syphilis. The height of rapid plasma reagin (RPR) titer was measured to determine the stage of the infection and to examine the success of the antilues therapy. The diagnosis of maternal syphilis infection was confirmed with enzyme linked immunosorbent assay (ELISA), T. pallidum particle agglutination (TPPA), and IgG and IgM immunoblots. Maternal IgM immunoblot results identify mothers at risk of delivering babies with connatal syphilis better than the height of maternal RPR titer. The standard serological tests are less useful in newborns because of IgG transfer across the placenta. IgM test which depends on the infant's response has more specificity in diagnosing connatal syphilis.