Cotesting for Human Immunodeficiency Virus and Sexually Transmitted Infections in the Emergency Department.

BACKGROUND: The Centers for Disease Control and Prevention (CDC) and US Preventive Services Task Force (USPSTF) guidelines recommend screening for human immunodeficiency virus (HIV) in patients aged 15 to 65 years, as well as those at increased risk. Patients screened in the emergency department (ED) for gonorrhea (GC) and/or chlamydia represent an increased-risk population. Our aim was to assess compliance with CDC and USPSTF guidelines for HIV testing in a national sample of EDs. METHODS: We examined data from the 2010 to 2018 Nationwide Emergency Department Sample, which can be used to create national estimates of ED care to query tests for GC, chlamydia, HIV, and syphilis testing. Weighted proportions and 95% confidence intervals (CIs) were reported, and Rao-Scott χ 2 tests were used. RESULTS: We identified 13,443,831 (weighted n = 3,094,214) high-risk encounters in which GC/chlamydia testing was performed. HIV screening was performed in 3.9% (95% CI, 3.4-4.3) of such visits, and syphilis testing was performed in 2.9% (95% CI, 2.7-3.2). Only 1.5% of patients with increased risk encounters received both HIV and syphilis cotesting. CONCLUSIONS: Despite CDC and USPSTF recommendations for HIV and syphilis screening in patients undergoing STI evaluation, only a small proportion of patients are being tested. Further studies exploring the barriers to HIV screening in patients undergoing STI assessment in the ED may help inform future projects aimed at increasing guidance compliance.

Severe acute respiratory syndrome coronavirus 2, original antigenic sin, and antibody-dependent enhancement: ménage à trois.

BACKGROUND: Shortly after its emergence in December 2019, the coronavirus disease 2019 (COVID-19) was declared as a pandemic by the World Health Organization. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is the seventh member of the Coronaviridae family of viruses that causes disease in humans. THE PROBLEM: Despite the established role of molecular diagnostics, COVID-19 serodiagnosis remains a poorly discovered and enigmatic area. Although there are numerous commercial serological products available globally, there is a severe paucity of high-quality peer-reviewed literature on their true performance characteristics. That being said, publications including in-house developed serological tests started to shed light on the kinetics of the humoral response. SUMMARY: In spite of intense focus of assessing the performance characteristics of the commercially-available kits, the main issue remains rather invisible, that is, lack of solid science behind COVID-19 serology its clinical usefulness thereof. This short review summarizes the key points as to why COVID-19 is not jest ready to fly. PURPOSE OF REVIEW: Despite having been mentioned as a testing option, COVID-19 serology has significant shortcomings that needs discussing. This short review is meant to shed light on one of those aspects.

The Role of Antibody Testing for SARS-CoV-2: Is There One?

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) brought with it rapid development of both molecular and serologic assays for identification of COVID-19 infections. While Food and Drug Administration (FDA) emergency use authorization (EUA) is required for clinical application of SARS-CoV-2 molecular tests, submission for EUA is currently a voluntary process for manufacturers of serologic assays. The absence of FDA oversight of serologic tests is concerning given that the commercially available serologic assays are highly variable, differing in their format, the antibody class detected, the targeted antigen, and the acceptable specimen types. An added complication is the lack of a clear understanding for how such assays should be utilized and what the reported results ultimately indicate or, perhaps more importantly, what they do not indicate. Here, we provide a brief summary of the performance of a number of serologic assays reported in the literature, comment on what we do and do not know regarding our immune response to SARS-CoV-2, and provide a number of scenarios for which serologic testing will play a role during our global response to this pandemic.

Evaluation of a new Strongyloides ELISA IgG Test Kit.

BACKGROUND: Strongyloides stercoralis poses a significant clinical and public health challenge not only in endemic regions but also in non-endemic regions associated with travel. Ruling out this infection is essential in immuno-compromised hosts given the high probability of reactivation and mortality. METHODS: In this study we compared an ELISA based on two recombinant antigens in the United States with a highly sensitive and specific reference serological test. RESULTS & CONCLUSION: There was 100% agreement between the two methods. ELISA assays based on Strongyloides stercoralis recombinant antigens has the potential to improve specificity. Further studies are warranted.

Operational Usability Evaluation of the LIAISON® QuantiFERON®-TB Gold Plus Solution in a High Volume Laboratory Setting.

BACKGROUND: Screening for latent tuberculosis infection (LTBI) using interferon gamma release assays has become commonplace for a variety of reasons. Given the high test volume, automated platforms are highly desired. METHODS: To this end, we performed an operational usability study using a newly FDA-approved, fully automated, random-access platform. RESULTS & CONCLUSIONS: Our results showed that this platform can save time and labor and will be a potential useful addition to streamline LTBI screening. Studies to verify performance characteristics are warranted.

Molecular Typing and Macrolide Resistance of Syphilis Cases in Manitoba, Canada, From 2012 to 2016.

BACKGROUND: The province of Manitoba, Canada, with a population of approximately 1.3 million, has been experiencing increased incidence of syphilis cases since 2015. In this study, we examined the detection of Treponema pallidum DNA in 354 clinical samples from 2012 to 2016, and determined molecular types and mutations conferring resistance to azithromycin in the polymerase chain reaction (PCR)-positive samples. METHODS: T. pallidum DNA detection was done by PCR amplification of tpp47, bmp, and polA genes. Syphilis serology results were reviewed for the PCR-positive cases. Molecular typing of syphilis strains was done by analysis of the T, pallidum arp, tpr, and tp0548 gene targets as well as partial sequencing of the 23S rRNA gene for azithromycin resistance. RESULTS: Of the 354 samples tested, 74 individual cases were PCR positive. A result from the treponemal antibody chemiluminescent microparticle immunoassay test was positive in 72 of these cases and that from the Venereal Disease Research Laboratory testing was positive in 66. Mutations conferring resistance to azithromycin were found in all 74 PCR-positive samples. Molecular typing was completed on 57 PCR-positive samples, and 12 molecular types were identified with 14d/g found in 63.2%. Increased strain diversity was observed with 8 molecular types detected in 2016, whereas only 2 to 3 types were found in 2012 to 2014. A patient with 2 episodes of infection 9 months apart caused by different molecular strain types was also identified. CONCLUSIONS: The finding of an increase in genetic diversity in the strains in this study and an increase in macrolide resistance compared with previous Canadian reports highlighted the need for continued surveillance including strain characterization.

Tonsillar Syphilis: an Unusual Site of Infection Detected by Treponema pallidum PCR.

With the reemergence of syphilis, it is important that both clinical and public health practitioners recognize the various clinical manifestations of this disease (formerly known as "the great imitator") and become familiar with the newer diagnostic tests. Here we report the first case of tonsillar syphilis diagnosed by PCR.

Canadian Public Health Laboratory Network laboratory guidelines for the use of direct tests to detect syphilis in Canada.

Treponema pallidum subsp. pallidum and/or its nucleic acid can be detected by various methods such as microscopy, rabbit infectivity test or polymerase chain reaction (PCR) tests. The rabbit infectivity test for T. pallidum, although very sensitive, has been discontinued from most laboratories due to ethical issues related to the need for animal inoculation with live T. pallidum, the technically demanding procedure and long turnaround time for results, thus making it impractical for routine diagnostic use. Dark-field and phase-contrast microscopy are still useful at clinic- or hospital-based laboratories for near-bedside detection of T. pallidum in genital, skin or mucous lesions although their availability is decreasing. The lack of reliable and specific anti-T. pallidum antibodies and its inferior sensitivity to PCR may explain why the direct fluorescent antibody test for T. pallidum is not widely available for clinical use. Immunohistochemical staining for T. pallidum also depends on the availability of specific antibodies, and the method is only applicable for histopathological examination of biopsy and autopsy specimens necessitating an invasive specimen collection approach. With recent advances in molecular diagnostics, PCR is considered to be the most reliable, versatile and practical for laboratories to implement. In addition to being an objective and sensitive test for direct detection of Treponema pallidum subsp. pallidum DNA in skin and mucous membrane lesions, the resulting PCR amplicons from selected gene targets can be further characterized for antimicrobial (macrolide) susceptibility testing, strain typing and identification of T. pallidum subspecies.

Diverses méthodes, telles que la microscopie, le test d'infectivité du lapin et la réaction en chaîne de la polymérase (PCR), permettent de déceler le Treponema pallidum sous-espèce pallidum et/ou son acide nucléique. Même s'il est très sensible, le test d'infectivité du lapin n'est plus utilisé dans la plupart des laboratoires pour déceler le T. pallidum. En effet, des raisons éthiques liées à la nécessité d'inoculer le T. pallidum vivant à l'animal, l'intervention exigeante sur le plan technique et la longue attente avant d'obtenir les résultats le rendent peu pratique pour un usage diagnostique régulier. Dans les laboratoires des cliniques ou des hôpitaux, la microscopie à fond noir et la microscopie à contraste de phase contribuent toujours à déceler le T. pallidum dans les lésions génitales, cutanées ou muqueuses près du chevet du patient, mais elles sont de moins en moins offertes. Le test d'immunofluorescence directe est peu utilisé pour diagnostiquer le T. pallidum en milieu clinique, peut-être en raison de l'absence d'anticorps anti-T. pallidum fiables et spécifiques et de sa faible sensibilité par rapport au PCR. La coloration immunohistochimique du T. pallidum dépend également de la présence d'anticorps spécifiques, et la méthode est applicable seulement à l'examen histopathologique des prélèvements invasifs de biopsies et d'autopsies. Étant donné les progrès récents des diagnostics moléculaires, la PCR est considérée comme le test le plus fiable, le plus polyvalent et le plus pratique à utiliser en laboratoire. Le PCR est objectif et spécifique pour la détection directe de l'ADN du Treponema pallidum sous-espèce pallidum dans les lésions de la peau et des muqueuses ; ses amplicons provenant de cibles géniques précises peuvent être caractérisés en vue de tests de susceptibilité antimicrobienne (aux macrolides), du typage des souches et du dépistage des sousespèces de T. pallidum.

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.

La syphilis, causée par la bactérie Treponema pallidum sous-espèce pallidum, est une infection connue depuis l'antiquité. Elle a été signalée pour la première fois en Europe, à la fin du XVe siècle. Les infections peuvent être transmises sexuellement, par une mère infectée à son fœtus ou par des transfusions sanguines. Il est difficile de diagnostiquer la syphilis en laboratoire. Puisque cet organisme ne peut pas être mis en culture, la sérologie est la principale méthode diagnostique. Parmi les problèmes liés aux diagnostics sérologiques, soulignons qu'il faut du temps pour que les anticorps fassent leur apparition après l'infection et que les tests de dépistage sérologique doivent s'associer à plusieurs tests de confirmation secondaires qui peuvent produire des résultats complexes devant être interprétés par des experts dans le domaine. Habituellement, la syphilis était dépistée au moyen du test rapide de la réagine plasmatique ou du test Veneral Disease Research Laboratory et était confirmée par les tests tréponémiques comme le MHA-TP, le TP-PA ou le FTA-Abs. Cette tendance s'inverse actuellement, car la plupart des laboratoires du Canada dépistent la syphilis au moyen d'épreuves immunoenzymatiques tréponémiques et confirment le statut de l'infection au moyen du test rapide de la réagine plasmatique ou du test Veneral Disease Reseach Laboratory. Cette approche est souvent désignée par le terme algorithme inversé. Ce chapitre analyse les directives sur les types de prélèvements et la collecte des échantillons, les tests tréponémiques et non tréponémiques utilisés au Canada, le statut actuel des tests sérologiques de la syphilis au Canada, la complexité du diagnostic sérologique d'infection par la syphilis et les algorithmes des tests sérologiques. Tant l'algorithme habituel que l'algorithme inversé sont recommandés, et l'algorithme utilisé devrait tenir compte à la fois de l'épidémiologie locale de la maladie, du volume de tests, de l'exécution des tests proposés et des ressources disponibles.

HCV antigen testing for the diagnosis of hepatitis C infection: a cost-efficient algorithm.

BACKGROUND: In North America, diagnosis of active hepatitis C virus (HCV) infection is currently performed using RNA testing which is highly sensitive and specific but is associated with three major limitations: lability of RNA molecules, higher costs, and longer turn-around time as compared with commercially-available HCV core antigen testing. In the current study, a new HCV core antigen assay product was evaluated for the diagnosis of HCV infection and its cost reducing potential. METHODS: Ninety plasma specimens positive for HCV RNA along with 25 negative HCV specimens were used for HCV antigen assay. Twenty-four specimens positive for a panel of agents were used for possible cross-reactivity. Sixty-four HCV antibody-positive specimens with negative HCV RNA and indeterminate HCV immunoblot results were also employed. RESULTS: In the first group, 78/90 (86.6%) tested positive for HCV antigen with regression analysis showing no significant deviation from linearity. None of the prenatal specimens tested positive for HCV antigen. Non-specific reactions were not observed. In the HCV antibody-indeterminate group, only 2/64 (3.1%) were antigen positive. In the last group, none of the HCV antibody very-low-positive specimens tested positive for HCV antigen. Both inter- and intra-run reproducibility of 100% were noted. The cost analysis showed a minimum of 52.13% reduction in costs associated with qualitative RNA testing. CONCLUSIONS: Considering the complexity of HCV infection diagnosis and the significant cost and turn-around time burden it imposes on clinical laboratories, HCV antigen testing seems an attractive adjunct to the current battery of laboratory diagnosis that demands more attention.

Post-COVID mRNA-vaccine IgG4 shift: worrisome?

COVID-19 vaccines play a key role in ending the pandemic. Unraveling the immunological phenomena involved in offering protective immunity is the cornerstone of achieving such success. This perspective evaluates the possible mechanisms and implications of IgG4 production in response to mRNA-based COVID-19 vaccines.

Emergency Department Co-testing for Human Immunodeficiency Virus When Testing for Gonorrhea and Chlamydia: A Readily Available, Missed Opportunity for Targeted HIV Testing in Emergency Departments.

OBJECTIVES: Conducting human immunodeficiency virus (HIV) testing in emergency departments (EDs) can be an effective approach to testing and reaching populations at highest risk of contracting HIV. METHODS: All gonorrhea and chlamydia (G/C) and HIV tests ordered in the Cleveland Clinic Health System's 14 EDs were included in the analysis. Data were collected from electronic health records. Descriptive statistics, with medians and means, were computed. RESULTS: From January 1, 2019, to December 31, 2021, we reviewed ED visits for the purpose of sexually transmitted infection (STI) screening, with an emphasis on G/C screening. In October 2019, both HIV rapid testing and G/C testing began across all 14 Cleveland Clinic EDs. The overall rate of co-testing for HIV when obtaining a G/C test for STI evaluation increased overall to around 30% for our health system EDs, with some individual EDs approaching 60%. CONCLUSIONS: The approach the Cleveland Clinic implemented is an effective way to test for HIV in the ED. Local health departments and stakeholders in HIV communities should support and collaborate with EDs in their jurisdictions to accelerate HIV testing initiatives by using an HIV plus G/C co-testing metric.

Local transmission of imported endemic syphilis, Canada, 2011.

Endemic (nonvenereal) syphilis is relatively common in nonindustrialized regions of the world. We describe a case of local transmission in Canada and review tools available for confirming a diagnosis. Improved molecular tools and global clinical awareness are needed to recognize cases of endemic syphilis imported to areas where it is not normally seen.

ICOS ligand expression is essential for allergic airway hyperresponsiveness.

Inducible co-stimulator ligand (ICOSL) is a rather newly defined co-stimulatory molecule, which, through interaction with ICOS expressed on T cells, plays an important role in T-cell activation, differentiation and function. T(h)2-type immune responses are critical for the development and maintenance of allergic responses including asthma. Using knockout (KO) mice, we have assessed the role of ICOSL in allergic airway inflammation and responsiveness using a standard mouse asthma model induced by ovalbumin (OVA) sensitization and challenge. Our data show that OVA-treated ICOSL KO mice exhibit significantly less lung eosinophilic infiltration, histopathology, mucus production and virtually no airway hyperresponsiveness in contrast to wild-type (Wt) counterparts. Serum antibody analysis showed that antigen-specific IgG1, IgG2a and IgE titers in ICOSL KO mice were significantly lower than those of Wt controls. Also, CD4(+) T cells isolated from ICOSL KO mice produced less T(h)2 cytokines (IL-4, IL-5, IL-10 and IL-13) but more T(h)1 (IFN-γ) and IL-17 than their Wt controls. Taken together, we conclude that ICOSL plays an important role in predisposing individuals to allergic airway hyperresponsiveness by enhancing IgE antibody class switching and T(h)2 cytokine production and diminishing the T(h)17 response and airway eosinophilia.