Acute rheumatic fever and rheumatic heart disease

Conservation of C4BP-binding Sequence Patterns in Streptococcus pyogenes M and Enn Proteins

Antigenically sequence variable M proteins of the major bacterial pathogen Streptococcus pyogenes (Strep A) are responsible for recruiting human C4b-binding protein (C4BP) to the bacterial surface, which enables Strep A to evade destruction by the immune system. The most sequence divergent portion of M proteins, the hypervariable region (HVR), is responsible for binding C4BP. Structural evidence points to the conservation of two C4BP-binding sequence patterns (M2 and M22) in the HVR of numerous M proteins, with this conservation applicable to vaccine immunogen design. These two patterns, however, only partially explain C4BP-binding by Strep A. Here, we identified several M proteins that lack these patterns but still bind C4BP, and determined the structures of two, M68 and M87 HVRs, in complex with a C4BP fragment. Mutagenesis of these M proteins led to identification of amino acids that are crucial for C4BP-binding, enabling formulation of new C4BP-binding patterns. Mutagenesis was also carried out on M2 and M22 proteins to refine or generate experimentally grounded C4BP-binding patterns. The M22 pattern was the most prevalent among M proteins, followed by the M87 and M2 patterns, while the M68 pattern was rare. These patterns, except for M68, were also evident in numerous M-like Enn proteins. Binding of C4BP via these patterns to Enn proteins was verified. We conclude that C4BP-binding patterns occur frequently in Strep A strains of differing M types, being present in their M or Enn proteins, or frequently both, providing further impetus for their use as vaccine immunogens.

Manganese uptake by MtsABC contributes to the pathogenesis of human pathogen group A streptococcus by resisting host nutritional immune defenses

The interplay between host nutritional immune mechanisms and bacterial nutrient uptake systems has a major impact on the disease outcome. The host immune factor calprotectin (CP) limits the availability of essential transition metals, such as manganese (Mn) and zinc (Zn), to control the growth of invading pathogens. We previously demonstrated that the competition between CP and the human pathogen group A streptococcus (GAS) for Zn impacts GAS pathogenesis. However, the contribution of Mn sequestration by CP in GAS infection control and the role of GAS Mn acquisition systems in overcoming host-imposed Mn limitation remain unknown. Using a combination of in vitro and in vivo studies, we show that GAS-encoded mtsABC is a Mn uptake system that aids bacterial evasion of CP-imposed Mn scarcity and promotes GAS virulence. Mn deficiency caused by either the inactivation of mtsC or CP also impaired the protective function of GAS-encoded Mn-dependent superoxide dismutase. Our ex vivo studies using human saliva show that saliva is a Mn-scant body fluid, and Mn acquisition by MtsABC is critical for GAS survival in human saliva. Finally, animal infection studies using wild-type (WT) and CP-/- mice showed that MtsABC is critical for GAS virulence in WT mice but dispensable in mice lacking CP, indicating the direct interplay between MtsABC and CP in vivo. Together, our studies elucidate the role of the Mn import system in GAS evasion of host-imposed metal sequestration and underscore the translational potential of MtsABC as a therapeutic or prophylactic target.

Exploring the relationship between infectious agents and autoimmune diseases: a review

The relationship between infectious agents and autoimmune diseases is a complex issue. In recent years, increasing clinical cases have indicated that infectious agents play an important role in the development of autoimmune diseases. Molecular mimicry is currently widely regarded as the primary pathogenic mechanism of various autoimmune diseases in humans. Components of infectious agents can undergo molecular mimicry with components in patients' bodies, leading to the development of various autoimmune diseases. In this article, we provide a brief overview of current research of the current research status on the relationship between infectious agents and autoimmune diseases, and describe our current understanding of their mechanisms of action in order to better understand the pathogenesis, diagnosis, and treatment of autoimmune diseases.

Novel insights into the immune response to bacterial T cell superantigens

Bacterial T cell superantigens (SAgs) are a family of microbial exotoxins that function to activate large numbers of T cells simultaneously. SAgs activate T cells by direct binding and crosslinking of the lateral regions of MHC class II molecules on antigen-presenting cells with T cell receptors (TCRs) on T cells; these interactions alter the normal TCR-peptide-MHC class II architecture to activate T cells in a manner that is independent of the antigen specificity of the TCR. SAgs have well-recognized, central roles in human diseases such as toxic shock syndrome and scarlet fever through their quantitative effects on the T cell response; in addition, numerous other consequences of SAg-driven T cell activation are now being recognized, including direct roles in the pathogenesis of endocarditis, bloodstream infections, skin disease and pharyngitis. In this Review, we summarize the expanding family of bacterial SAgs and how these toxins can engage highly diverse adaptive immune receptors. We highlight recent findings regarding how SAg-driven manipulation of the adaptive immune response may operate in multiple human diseases, as well as contributing to the biology and life cycle of SAg-producing bacterial pathogens.

Prevalence of rheumatic heart disease diagnosed according to the echocardiographic criteria of the World Heart Federation in Africa: A systematic review and meta-analysis

Rheumatic heart disease (RHD) is a chronic complication arising from acute rheumatic fever (ARF), an autoimmune response triggered by group A streptococcal infection. It primarily affects children and young adults in developing countries. RHD continues to show substantial global heterogeneity. Socioeconomic factors lead the virtual disappearance of RHD in industrialized countries with the introduction of penicillin. By contrast, RHD is still endemic in Africa, Asia, South America, and developing communities of Australasia. We provide an estimate of the current prevalence of latent RHD in Africa using the echocardiographic diagnostic criteria of the World Heart Federation (WHF). Systematic review and meta-analysis of 21 studies reporting the prevalence of RHD, encompassing 40.639 patients. Estimated prevalence of RHD was 25.5 cases per 1000 population (P ≤0.02; 95 % CI, 18.1-32.9 per 1000): definite RHD 13.1 cases per 1000 population (95 % CI, 7.7-18.5 per 1000): and borderline 12,4 cases per 1000 population (95 % CI, 7.7-17.0 per 1000). The prevalence of definite RHD was a significantly higher in adults (M = 28.2, SD = 6.1) compared to children (M = 10.3, SD = 9.2), t(17) = 2.6, p = .0179. Prevalence of definite RHD in schools was 7,92 cases per 1000 population (95 % CI, 4,49-11,35 per 1000) and in community was 26,17 cases per 1000 population (95 % CI, 12,27-40,06 per 1000). This meta-analysis may have produced a better estimate of the prevalence of RHD in Africa using only studies performed according to the 2012 WHF, and clearly showed the high prevalence of RHD in the community and in adults.

"Hurts less, lasts longer"; a qualitative study on experiences of young people receiving high-dose subcutaneous injections of benzathine penicillin G to prevent rheumatic heart disease in New Zealand

BACKGROUND

Four-weekly intramuscular (IM) benzathine penicillin G (BPG) injections to prevent acute rheumatic fever (ARF) progression have remained unchanged since 1955. A Phase-I trial in healthy volunteers demonstrated the safety and tolerability of high-dose subcutaneous infusions of BPG which resulted in a much longer effective penicillin exposure, and fewer injections. Here we describe the experiences of young people living with ARF participating in a Phase-II trial of SubCutaneous Injections of BPG (SCIP).

METHODOLOGY

Participants (n = 20) attended a clinic in Wellington, New Zealand (NZ). After a physical examination, participants received 2% lignocaine followed by 13.8mL to 20.7mL of BPG (Bicillin-LA®; determined by weight), into the abdominal subcutaneous tissue. A Kaupapa Māori consistent methodology was used to explore experiences of SCIP, through semi-structured interviews and observations taken during/after the injection, and on days 28 and 70. All interviews were recorded, transcribed verbatim, and thematically analysed.

PRINCIPAL FINDINGS

Low levels of pain were reported on needle insertion, during and following the injection. Some participants experienced discomfort and bruising on days one and two post dose; however, the pain was reported to be less severe than their usual IM BPG. Participants were 'relieved' to only need injections quarterly and the majority (95%) reported a preference for SCIP over IM BPG.

CONCLUSIONS

Participants preferred SCIP over their usual regimen, reporting less pain and a preference for the longer time gap between treatments. Recommending SCIP as standard of care for most patients needing long-term prophylaxis has the potential to transform secondary prophylaxis of ARF/RHD in NZ and globally.

Outcome following acute and recurrent rheumatic fever

BACKGROUND

Rheumatic carditis is the leading cause of permanent disability caused by damage of the cardiac valve. This study aimed to determine the outcome and predictors of valve surgery in patients with acute rheumatic fever (ARF) and recurrent rheumatic fever (RRF).

METHODS

This was a retrospective study of patients diagnosed with ARF and RRF between 2006 and 2021. The predictors of valve surgery were analysed using multivariable Cox proportional regression.

RESULTS

The median age of patients with ARF and RRF (n=92) was 11 years (range 5-18). Seventeen patients (18%) were diagnosed with RRF. The most common presenting symptoms included clinical carditis (87%), heart failure (HF) (63%), fever (49%) and polyarthralgia (24%). Patients with moderate-to-severe rheumatic carditis (88%) were given prednisolone. After treatment, the severity of valvular regurgitation was reduced in 52 patients (59%). Twenty-three patients (25%) underwent valve surgery. The incidence of HF, RRF, severe mitral regurgitation on presentation, left ventricular enlargement and pulmonary hypertension was greater in the surgical group than in the non-surgical group. Recurrent rheumatic fever (hazard ratio 7.9, 95% CI 1.9-33.1), tricuspid regurgitation (TR) gradient ≥ 42 mmHg (HR 6.3, 95%CI 1.1-38.7) and left ventricular end-diastolic dimension (LVEDD) ≥6 cm (HR 8.7, 95% CI 2.1-35.9) were predictors of valve surgery (multivariable Cox proportional regression analysis).

CONCLUSION

Clinical carditis was the most common presenting symptom in patients with ARF and RRF. The majority of patients responded positively to prednisolone. These findings highlight the predictors of valve surgery following ARF, including RRF, TR gradient ≥ 42 mmHg and LVEDD ≥ 6 cm.Abbreviations: ARF: acute rheumatic fever; CRP: C-reactive protein; ESR: erythrocyte sedimentation rate; GAS: group A beta-haemolytic Streptococcus; HF: heart failure; HR: hazard ratio; LVEDD: left ventricular end-diastolic dimension; MR: mitral regurgitation; RHD: rheumatic heart disease; RRF: recurrent rheumatic fever; TR: tricuspid regurgitation.

Eliminate all risks: A call to reexamine the link between canine scabies and rheumatic heart disease

Rheumatic heart disease (RHD) and acute rheumatic fever (ARF) disproportionately affect individuals in low-resource settings. ARF is attributed to an immune response to Group A Streptococcus (GAS) following GAS pharyngitis and potentially GAS impetigo in which infection can be initiated by scabies infestation. The burden of ARF and RHD in Aboriginal and Torres Strait Islander people in Australia is among the highest globally. Following recent calls to include dog management programs in ARF and RHD prevention programs, we believe it is timely to assess the evidence for this, particularly since previous recommendations excluded resources to prevent zoonotic canine scabies. While phylogenetic analyses have suggested that the Sarcoptes mite is host specific, they have differed in interpretation of the strength of their findings regarding species cross-over and the need for canine scabies control to prevent human itch. Given that there is also indication from case reports that canine scabies leads to human itch, we propose that further investigation of the potential burden of zoonotic canine scabies and intervention trials of canine scabies prevention on the incidence of impetigo are warranted. Considering the devastating impacts of ARF and RHD, evidence is required to support policy to eliminate all risk factors.

A flow cytometry-based assay to determine the ability of anti-Streptococcus pyogenes antibodies to mediate monocytic phagocytosis in human sera

Streptococcus pyogenes, commonly referred to as Group A Streptococcus (Strep A), causes a spectrum of diseases, with the potential to progress into life-threatening illnesses and autoimmune complications. The escalating threat of antimicrobial resistance, stemming from the prevalent reliance on antibiotic therapies to manage Strep A infections, underscores the critical need for the development of disease control strategies centred around vaccination. Phagocytes play a critical role in controlling Strep A infections, and phagocytosis-replicating assays are essential for vaccine development. Traditionally, such assays have employed whole-blood killing or opsonophagocytic methods using HL-60 cells as neutrophil surrogates. However, assays mimicking Fcγ receptors- phagocytosis in clinical contexts are lacking. Therefore, here we introduce a flow cytometry-based method employing undifferentiated THP-1 cells as monocytic/macrophage model to swiftly evaluate the ability of human sera to induce phagocytosis of Strep A. We extensively characterize the assay's precision, linearity, and quantification limit, ensuring robustness. By testing human pooled serum, the assay proved to be suitable for the comparison of human sera's phagocytic capability against Strep A. This method offers a valuable complementary assay for clinical studies, addressing the gap in assessing FcγR-mediated phagocytosis. By facilitating efficient evaluation of Strep A -phagocyte interactions, it may contribute to elucidating the mechanisms required for the prevention of infections and inform the development of future vaccines and therapeutic advancements against Strep A infections.

Securing the supply of benzathine penicillin: a global perspective on risks and mitigation strategies to prevent future shortages

Benzathine benzylpenicillin is a globally indispensable medicine. As a long-lasting injectable penicillin, it serves as the primary treatment for syphilis, group A streptococcal infections, rheumatic fever and rheumatic heart disease. A competitive market and low profit margins, compounded by limited visibility of demand, have resulted in a decreased number of active pharmaceutical ingredient (API) manufacturers. By 2016, only three Chinese API manufacturers remained, continuing to supply to the global market today. Recurring global shortages, a consequence of supply and demand imbalances, indicate underlying market risks. Therefore, the need for mitigation strategies is imperative.

The role of deubiquitinases in cardiac disease

Deubiquitinases are a group of proteins that identify and digest monoubiquitin chains or polyubiquitin chains attached to substrate proteins, preventing the substrate protein from being degraded by the ubiquitin-proteasome system. Deubiquitinases regulate cellular autophagy, metabolism and oxidative stress by acting on different substrate proteins. Recent studies have revealed that deubiquitinases act as a critical regulator in various cardiac diseases, and control the onset and progression of cardiac disease through a board range of mechanism. This review summarizes the function of different deubiquitinases in cardiac disease, including cardiac hypertrophy, myocardial infarction and diabetes mellitus-related cardiac disease. Besides, this review briefly recapitulates the role of deubiquitinases modulators in cardiac disease, providing the potential therapeutic targets in the future.

Assessment and Treatment of Abnormal Involuntary Movements: A Clinically Focused Narrative Review

LEARNING OBJECTIVES

After participating in this CME activity, the psychiatrist should be better able to:• Categorize and describe different types of abnormal involuntary movements (AIMs).• Identify assessment tools and treatment options for AIMs.

ABSTRACT

Abnormal involuntary movements (AIMs) comprise a diverse group of movement disorders characterized by uncontrolled and unintended movements (e.g., tremors, tics, dystonia). AIMs can occur at any stage of life and pose significant challenges for clinicians. It is difficult to determine their underlying causes due to the complex neurobiological mechanisms involved. Therefore, it is crucial to quantify the severity and progression of AIMs using well-validated measurement scales, such as the Abnormal Involuntary Movement Scale (AIMS). By employing reliable assessment approaches, clinicians can objectively evaluate the motoric manifestations of AIMs and track them over time. Treatment of AIMs varies depending on their nature and etiology. While AIMs often respond to treatment, serious side effects can undermine treatment efficacy. In this clinically focused narrative review, we categorize different types of AIMs and discuss their neurobiological aspects. Further, we emphasize the importance of using well-validated measurement scales for accurate assessment and discuss available treatment modalities that target the specific AIMs manifestations. Additionally, we cover the need for comprehensive care to address the multifaceted nature of AIMs, accounting for their physical manifestations as well as their psychological, social, and functional toll on patients. By embracing a multidisciplinary approach, health care professionals can provide patient-centered care that promotes overall well-being and enhances the lives of patients coping with AIMs. Regular follow-up assessments are necessary to monitor treatment response, adjust medications when needed, and provide ongoing support for individuals affected by AIMs.

Application of Transthoracic Echocardiography for Cardiac Safety Evaluation in the Clinical Development Process of Vaccines Against Streptococcus pyogenes

Superficial infections with Streptococcus pyogenes (Strep A), pharyngitis and impetigo can induce acute rheumatic fever, an autoimmune sequela manifesting mostly with arthritis and rheumatic carditis. Valvular heart damage can persist or advance following repeated episodes of acute rheumatic fever, causing rheumatic heart disease. Acute rheumatic fever and rheumatic heart disease disproportionately affect children and young adults in developing countries and disadvantaged communities in developed countries. People living with rheumatic heart disease are at risk of experiencing potentially fatal complications such as heart failure, bacterial endocarditis or stroke. Transthoracic echocardiography plays a central role in diagnosing both rheumatic carditis and rheumatic heart disease. Despite the obvious medical need, no licensed Strep A vaccines are currently available, as their clinical development process faces several challenges, including concerns for cardiac safety. However, the development of Strep A vaccines has been recently relaunched by many vaccine developers. In this context, a reliable and consistent safety evaluation of Strep A vaccine candidates, including the use of transthoracic echocardiography for detecting cardiac adverse events, could greatly contribute to developing a safe and efficacious product in the near future. Here, we propose a framework for the consistent use of transthoracic echocardiography to proactively detect cardiac safety events in clinical trials of Strep A vaccine candidates.

Outcomes of rheumatic fever in Uganda: a prospective cohort study

BACKGROUND

Rheumatic heart disease is the largest contributor to cardiac-related mortality in children worldwide. Outcomes in endemic settings after its antecedent illness, acute rheumatic fever, are not well understood. We aimed to describe 3-5 year mortality, acute rheumatic fever recurrence, changes in carditis, and correlates of mortality after acute rheumatic fever.

METHODS

We conducted a prospective cohort study of Ugandan patients aged 4-23 years who were diagnosed with definite acute rheumatic fever using the modified 2015 Jones criteria from July 1, 2017, to March 31, 2020, enrolled at three rheumatic heart disease registry sites in Uganda (in Mbarara, Mulago, or Lira), and followed up for at least 1 year after diagnosis. Patients with congenital heart disease were excluded. Patients underwent annual review, most recently in August, 2022. We calculated rates of mortality and acute rheumatic fever recurrence, tabulated changes in carditis, performed Kaplan-Meier survival analyses, and used Cox regression models to identify correlates of mortality.

FINDINGS

Data were collected between Sept 1 and Sept 30, 2022. Of 182 patients diagnosed with definite acute rheumatic fever, 156 patients were included in the analysis. Of these 156 patients (77 [49%] male and 79 (51%) female; data on ethnicity not collected), 25 (16%) died, 21 (13%) had a cardiac-related death, and 17 (11%) had recurrent acute rheumatic fever over a median of 4·3 (IQR 3·0-4·8) years. 16 (24%) of the 25 deaths occurred within 1 year. Among 131 (84%) of 156 survivors, one had carditis progression by echo. Moderate-to-severe carditis (hazard ratio 12·7 [95% CI 3·9-40·9]) and prolonged PR interval (hazard ratio 4·4 [95% CI 1·7-11·2]) at acute rheumatic fever diagnosis were associated with increased cardiac-related mortality.

INTERPRETATION

These are the first contemporary data from sub-Saharan Africa on medium-term acute rheumatic fever outcomes. Mortality rates exceeded those reported elsewhere. Most decedents already had chronic carditis at initial acute rheumatic fever diagnosis, suggesting previous undiagnosed episodes that had already compounded into rheumatic heart disease. Our data highlight the large burden of undetected acute rheumatic fever in these settings and the need for improved awareness of and diagnostics for acute rheumatic fever to allow earlier detection.

FUNDING

Strauss Award at Cincinnati Children's Hospital, American Heart Association, and Wellcome Trust.

Fatal Myocarditis following COVID-19 mRNA Immunization: A Case Report and Differential Diagnosis Review

Carditis in childhood is a rare disease with several etiologies. We report a case of infant death due to pericarditis and myocarditis after the mRNA vaccine against COVID-19 (COVIDmRNAV). A 7-year-old male child received the first dose of the COVIDmRNAV and presented with monoarthritis and a fever non-responsive to oral antibiotics. The laboratory investigation showed signs of infection (leukocytosis, high levels of c-reactive protein). His condition rapidly deteriorated, and the patient died. The autopsy identified pericardial fibrin deposits, hemorrhagic areas in the myocardium, and normal valves. A diffuse intermyocardial inflammatory infiltrate composed of T CD8+ lymphocytes and histiocytes was identified. An antistreptolysin O (ASO) dosage showed high titers. The presence of arthritis, elevated ASO, and carditis fulfills the criteria for rheumatic fever. However, valve disease and Aschoff's nodules, present in 90% of rheumatic carditis cases, were absent in this case. The temporal correlation with mRNA vaccination prompted its inclusion as one of the etiologies. In cases of myocardial damage related to COVID-19mRNAV, it appears to be related to the expression of exosomes and lipid nanoparticles, leading to a cytokine storm. The potential effects of the COVID-19mRNAV must be considered in the pathogenesis of this disease, whether as an etiology or a contributing factor to a previously initiated myocardial injury.

Beyond the acute phase: a comprehensive literature review of long-term sequelae resulting from infectious diseases

Infectious diseases have consistently served as pivotal influences on numerous civilizations, inducing morbidity, mortality, and consequently redirecting the course of history. Their impact extends far beyond the acute phase, characterized by the majority of symptom presentations, to a multitude of adverse events and sequelae that follow viral, parasitic, fungal, or bacterial infections. In this context, myriad sequelae related to various infectious diseases have been identified, spanning short to long-term durations. Although these sequelae are known to affect thousands of individuals individually, a comprehensive evaluation of all potential long-term effects of infectious diseases has yet to be undertaken. We present a comprehensive literature review delineating the primary sequelae attributable to major infectious diseases, categorized by systems, symptoms, and duration. This compilation serves as a crucial resource, illuminating the long-term ramifications of infectious diseases for healthcare professionals worldwide. Moreover, this review highlights the substantial burden that these sequelae impose on global health and economies, a facet often overshadowed by the predominant focus on the acute phase. Patients are frequently discharged following the resolution of the acute phase, with minimal long-term follow-up to comprehend and address potential sequelae. This emphasizes the pressing need for sustained vigilance, thorough patient monitoring, strategic health management, and rigorous research to understand and mitigate the lasting economic and health impacts of infectious diseases more fully.

State transitions across the Strep A disease spectrum: scoping review and evidence gaps

The spectrum of diseases caused by Streptococcus pyogenes (Strep A) ranges from superficial to serious life-threatening invasive infections. We conducted a scoping review of published articles between 1980 and 2021 to synthesize evidence of state transitions across the Strep A disease spectrum. We identified 175 articles reporting 262 distinct observations of Strep A disease state transitions. Among the included articles, the transition from an invasive or toxin-mediated disease state to another disease state (i.e., to recurrent ARF, RHD or death) was described 115 times (43.9% of all included transition pairs) while the transition to and from locally invasive category was the lowest (n = 7; 0.02%). Transitions from well to any other state was most frequently reported (49%) whereas a relatively higher number of studies (n = 71) reported transition from invasive disease to death. Transitions from any disease state to locally invasive, Strep A pharyngitis to invasive disease, and chronic kidney disease to death were lacking. Transitions related to severe invasive diseases were more frequently reported than superficial ones. Most evidence originated from high-income countries and there is a critical need for new studies in low- and middle-income countries to infer the state transitions across the Strep A disease spectrum in these high-burden settings.

Cerebrospinal fluid findings in patients with obsessive-compulsive disorder, Tourette syndrome, and PANDAS: A systematic literature review

BACKGROUND

Obsessive-compulsive disorder (OCD) and Tourette syndrome (TS) are related mental disorders that share genetic, neurobiological, and phenomenological features. Pediatric autoimmune neuropsychiatric disorder associated with streptococcal infections (PANDAS) is a neuropsychiatric autoimmune disorder with symptoms of OCD and/or TS associated with streptococcal infections. Therefore, PANDAS represents a strong link between OCD, TS, and autoimmunity. Notably, cerebrospinal fluid (CSF) analyses can provide insight into the central nervous processes in OCD, TS, and PANDAS.

METHODS

A systematic literature search according to the PRISMA criteria was conducted to collect all CSF studies in patients with OCD, TS, and PANDAS. The total number of cases and the heterogeneity of the low number of studies were not sufficient for a meta-analysis to provide a high level of evidence. Nevertheless, meta-analytical statistics could be performed for glutamate, 5-hydroxyindoleacetic acid (degradation product of serotonin), homovanillic acid (degradation product of dopamine), 3-methoxy-4-hydroxyphenylglycol (major metabolite of noradrenaline), and corticotropin-releasing hormone (CRH) in OCD. A risk-of-bias assessment was implemented using the Cochrane ROBINS-E tool.

RESULTS

Meta-analytical testing identified elevated glutamate levels in the CSF of OCD patients compared with healthy controls, while no significant differences were found in other neurotransmitters or CRH. Single studies detected novel neuronal antibodies in OCD patients and elevated oligoclonal bands in TS patients. For TS and PANDAS groups, there was a dearth of data. Risk of bias assessment indicated a substantial risk of bias in most of the included studies.

CONCLUSIONS

This systematic review of available CSF data shows that too few studies are currently available for conclusions with good evidence. The existing data indicates glutamate alterations in OCD and possible immunological abnormalities in OCD and TS. More CSF studies avoiding sources of bias are needed.

Knowledge and Attitude of Rheumatic Fever and Rheumatic Heart Disease Among the Makkah City Population, Saudi Arabia

Background Rheumatic heart disease (RHD) is a prominent sequela of rheumatic fever (RF) and the most common cause of acquired valvular disease worldwide. Patients develop RHD as a result of autoimmune reactions caused by an untreated group A Streptococcus (GAS) throat infection, resulting in significant valvular destruction. Objectives The current study aimed to assess the knowledge and attitude of RF and RHD among the Makkah city population in Saudi Arabia. Methods An observational cross-sectional study was conducted on a convenience sample of 1364 adult participants from Makkah city in Saudi Arabia. Data were collected through an online survey that was disseminated on different electronic platforms. Then, the obtained data were analyzed using SPSS version 23 (IBM Corp., Armonk, New York, USA). Results A total of 1364 participants completed the questionnaire; female participants constituted 58.1% (n = 792) and those between 18 and 30 years old represented 57.6% of the sample (n = 785). Knowledge of rheumatic fever was classified as poor (31.9%, n = 435), fair (44.8%, n = 611), and good (23.3%, n = 318). Female participants were shown to have better knowledge than males (p = 0.034). The attitude toward rheumatic fever and rheumatic heart disease was classified as negative (27.9%, n = 380), neutral (49.1%, n = 670), and positive (23%, n = 314). Conclusions This study concludes that adults in Makkah city, Saudi Arabia, have poor knowledge about RF and RHD. There is a notable gap in their knowledge regarding the association between sore throat and RF, bacterial dermatitis and RF, the common age for RF, and the necessity of using antibiotics appropriately to prevent this disease. The study also revealed negative attitudes toward RF and RHD among Makkah citizens, but most of them recommended health education campaigns to increase public awareness about this important disease. The results of this study will assist in the development of awareness campaigns about RF and RHD. Finally, qualitative studies are recommended to fully understand what the population perceives about this morbidity.

Echocardiographic Screening of Rheumatic Heart Disease: Current Concepts and Challenges

The incidence of acute rheumatic fever (ARF), which most commonly affects children aged 5-15 years after group A Streptococcus (GAS) infection, ranges from 8 to 51 per 100 000 people worldwide. Rheumatic heart disease (RHD), which occurs when patients with ARF are inappropriately treated or not given regular prophylaxis, is the most common cause of non-congenital heart disease in children and young adults in low-income countries. Timely treatment of GAS infection can prevent ARF, and penicillin prophylaxis can prevent recurrence of ARF. Secondary prophylaxis with benzathine penicillin G has been shown to decrease the incidence of RHD and is a key aspect of RHD control. The most important factor determining the prognosis of RHD is the severity of cardiac involvement. Although approximately 70% of patients with carditis in the acute phase of the disease recover without sequelae, carditis is important because it is the only complication of ARF that causes sequelae. One-third of patients with ARF are asymptomatic. Patients with mild symptoms of recurrent ARF and silent RHD will develop severe morbidities within 5-10 years if they do not receive secondary preventive treatments. A new screening program should be established to prevent cardiac morbidities of ARF in moderate- and highrisk populations. In the present study, we examined the applicability of echocardiographic screening programs for RHD. Cite this article as: Topçu S, Uçar T. Echocardiographic screening of rheumatic heart disease: Current concepts and challenges. Turk Arch Pediatr. 2024;59(1):3-12.

Rheumatology Training for Undergraduate Medical Students in Uganda: A Need Assessment Survey

Objectives

Despite the rise in the common rheumatological and musculoskeletal disorders (RMDs) in Africa, rheumatology remains an under recognized field with limited training and exposure of medical students. We assessed the knowledge of undergraduate medical students in Uganda on RMDs occurring in our settings.

Methods

A descriptive cross-sectional study was conducted among clinical year medical students at 9 universities in Uganda offering undergraduate medical degrees in March and April 2022. A self-administered, semistructured questionnaire was used to collect data on sociodemographic characteristics and basic knowledge on RMDs online using KoboToolbox. Sufficient knowledge was defined as a score of ≥50% (pass mark for undergraduate students in Uganda). Multivariable logistic regression was performed using STATA 16 to determine factors associated with knowledge acquisition on RMDs.

Results

We enrolled 359 medical students from 9 medical training institutes across Uganda. Overall, 126 (35.1%) participants had sufficient knowledge and the overall mean score for all participants was 41.2%. Factors independently associated with sufficient knowledge were: being in fourth (adjusted odds ratio [aOR]: 2.6, 95% confidence interval [CI]: 1.49-4.64, P < .001) and fifth year (aOR: 2.2, 95% CI: 1.18-4.18, P = .013) compared to third year of study, awareness of the speciality of rheumatology (aOR: 4.0, 95% CI: 1.96-8.06, P < .001), formal classes on rheumatology (aOR: 2.0, 95% CI: 1.15-3.35, P = .012), prior bedside teaching on RMDs (aOR: 2.3, 95% CI: 1.49-3.69, P < .001), awareness of common RMDs (aOR: 3.2, 95% CI: 1.67-6.04, P < .001), and having seen a patient with an RMD (aOR: 1.8, 95% CI: 1.14-2.77, P < .01).

Conclusion

There was a significant knowledge gap among undergraduate medical students nationwide on rheumatology. There is an urgent need to increase exposure to RMDs for undergraduate medical students to address the rising burden of RMDs in Uganda.

Trends in Rheumatic Heart Disease-Related Mortality in the United States from 1999 to 2020

There is a lack of mortality data on rheumatic heart disease (RHD) in the United States (US). In light of this, a retrospective analysis was conducted to investigate the temporal, sex-based, racial, and regional trends in RHD-related mortality in the US, ranging from 1999 to 2020. The Center for Disease Control and Prevention Wide-Ranging Online Data for Epidemiologic Research (CDC-WONDER) dataset was analyzed, where crude and age-adjusted mortality rates (AAMR) were identified, along with annual percentage changes (APCs) determined by Joinpoint regression. Through the period of 1999 to 2020, there were 141,137 RHD-related deaths reported, with a marginal decline from 4.05/100,000 in 1999 to 3.12/100,000 in 2020. However, the recent rise in AAMR from 2017 to 2020 has created a source of concern (APC: 6.62 [95% CI, 3.19-8.72]). Similar trends were observed in the Black or African American race from 2017 to 2020 (APC: 10.58 [95% CI, 6.29-17.80]). Moreover, the highest percentage change from 2018 to 2020 was observed in residents of large metropolitan areas (APC: 7.6 [95% CI, 2.8-10.5]). A prominent disparity was observed among states, with values ranging from 1.74/100,000 in Louisiana to 5.27/100,000 in Vermont. States within the top 90th percentile of RHD-related deaths included Alaska, Minnesota, Washington, Wyoming, and Vermont. In conclusion, it is imperative to delve deeper into the evidently rising trends of RHD-related mortality and outline the possible sources of social determinants within US healthcare in order to provide equal and quality medical care throughout the nation.

Temporal Trends of Age-Adjusted Mortality Rates for Rheumatic Heart Disease in Brazil From 2000 to 2021

Background Rheumatic heart disease (RHD) is a chronic cardiovascular condition stemming from an infectious origin, posing a substantial health burden, particularly in economically disadvantaged regions. It starts with acute rheumatic fever (ARF), a complication following group A Streptococcus infection, leading to heart valve damage and, over time, structural heart abnormalities. RHD contributes to premature deaths, especially in low-middle-income countries. Although the incidence and prevalence have generally reduced globally due to antibiotics and improved healthcare, it remains a significant public health concern in Brazil, echoing its prevalence in many developing nations around the world. RHD stands as a poignant testament to the intersection of socio-economic disparities and healthcare challenges within Brazil's diverse population. In Brazil, despite advancements in healthcare, RHD continues to impact communities, highlighting the urgent need for enhanced prevention strategies, access to quality healthcare services, and heightened awareness to combat this preventable, yet persistent, cardiac condition. Understanding the epidemiological landscape and socio-cultural factors influencing RHD in Brazil is crucial for developing targeted interventions aimed at mitigating its burden on individuals, families, and the healthcare system at large. Thus, our study focuses on analyzing age-related mortality rates linked to ARF and chronic RHD (ARHD) in Brazil from 2000 to 2021, particularly examining gender disparities. Materials and methods This retrospective cohort study employed a descriptive time-series approach, utilizing comprehensive nationwide data from Brazil spanning from 2000 to 2021 to assess trends in diverse age groups, among both sexes, enabling a detailed analysis of temporal patterns. Mortality data, extracted and categorized meticulously, were subjected to Joinpoint statistical analyses enabling comparative assessments, with average annual percent change (AAPC) and annual percent change (APC) serving as key metrics to quantify and interpret trends over the analyzed period. Results The acute RHD (ARHD)-related mortality declined over the analyzed years supported by AAPC, with higher mortality reduction in females. The age-adjusted mortality rate for "males and females" decreased from 78 to 67 deaths/100,000 from 2000 to 2021. Female mortality dropped from 85 to 69/100,000, and male mortality decreased from 73 to 63/100,000 over the same period. For ARHD, male age groups (20-29, 60-69, 70-79, 80+) showed declining mortality, while the 30-59 age group exhibited an upward. Females AAMR for chronic RHD (CRHD) decreased across all age groups, with significant reductions in the 80 years and above age group from 2000-2002 (APC: -11.94*) and steadily from 2002 onwards (APC: -1.33). Conclusions Our study revealed an overall decline in mortality rates for both acute and CRHD across both sexes. Females consistently exhibited higher mortality rates and a more pronounced reduction compared to males in both acute and CRHD. In ARHD, males experience the highest mortality in the 50-59 age group, while females have a peak in the 40-49 age group. The 60-69 age group had the highest mortality in CRHD for both sexes. Conversely, the 20-29 age group displayed the lowest mortality in CRHD, and the 80-89 age group had the lowest mortality in ARHD.

Anti-Idiotypic mRNA Vaccine to Treat Autoimmune Disorders

The 80+ existing autoimmune disorders (ADs) affect billions with little prevention or treatment options, except for temporary symptomatic management, leading to enormous human suffering and a monumental financial burden. The autoantibodies formed in most ADs have been identified, allowing the development of novel anti-idiotypic antibodies to mute the autoantibodies using vaccines. Nucleoside vaccines have been successfully tested as antigen-specific immunotherapies (ASI), with mRNA technology offering multi-epitope targeting to mute multiple autoantibodies. This paper proposes using mRNA technology to produce anti-idiotypic antibodies with broad effectiveness in preventing and treating them. This paper delves into the state-of-the-art mRNA design strategies used to develop novel ASIs by selecting appropriate T cell and B cell epitopes to generate anti-idiotypic antibodies. The low cost and fast development of mRNA vaccines make this technology the most affordable for the global control of ADs.

Research opportunities for the primordial prevention of rheumatic fever and rheumatic heart disease-streptococcal vaccine development: a national heart, lung and blood institute workshop report

Streptococcus pyogenes, also known as group A streptococcus (StrepA), is a bacterium that causes a range of human diseases, including pharyngitis, impetigo, invasive infections, and post-infection immune sequelae such as rheumatic fever and rheumatic heart disease. StrepA infections cause some of the highest burden of disease and death in mostly young populations in low-resource settings. Despite decades of effort, there is still no licensed StrepA vaccine, which if developed, could be a cost-effective way to reduce the incidence of disease. Several challenges, including technical and regulatory hurdles, safety concerns and a lack of investment have hindered StrepA vaccine development. Barriers to developing a StrepA vaccine must be overcome in the future by prioritising key areas of research including greater understanding of StrepA immunobiology and autoimmunity risk, better animal models that mimic human disease, expanding the StrepA vaccine pipeline and supporting vaccine clinical trials. The development of a StrepA vaccine is a complex and challenging process that requires significant resources and investment. Given the global burden of StrepA infections and the potential for a vaccine to save lives and livelihoods, StrepA vaccine development is an area of research that deserves considerable support. This report summarises the findings of the Primordial Prevention Working Group-VAX, which was convened in November 2021 by the National Heart, Lung, and Blood Institute. The focus of this report is to identify research gaps within the current StrepA vaccine landscape and find opportunities and develop priorities to promote the rapid and successful advancement of StrepA vaccines.

The Group A Streptococcal Vaccine Candidate VAX-A1 Protects against Group B Streptococcus Infection via Cross-Reactive IgG Targeting Virulence Factor C5a Peptidase

Group B Streptococcus (Streptococcus agalactiae or GBS) is the leading infectious cause of neonatal mortality, causing roughly 150,000 infant deaths and stillbirths annually across the globe. Approximately 20% of pregnant women are asymptomatically colonized by GBS, which is a major risk factor for severe fetal and neonatal infections as well as preterm birth, low birth weight, and neurodevelopmental abnormalities. Current clinical interventions for GBS infection are limited to antibiotics, and no vaccine is available. We previously described VAX-A1 as a highly effective conjugate vaccine against group A Streptococcus that is formulated with three antigens, SpyAD, streptolysin O, and C5a peptidase (ScpA). ScpA is a surface-expressed, well-characterized GAS virulence factor that shares nearly identical sequences with the lesser studied GBS homolog ScpB. Here, we show that GBS C5a peptidase ScpB cleaves human complement factor C5a and contributes to disease severity in the murine models of pneumonia and sepsis. Furthermore, antibodies elicited by GAS C5a peptidase bind to GBS in an ScpB-dependent manner, and VAX-A1 immunization protects mice against lethal GBS heterologous challenge. These findings support the contribution of ScpB to GBS virulence and underscore the importance of choosing vaccine antigens; a universal GAS vaccine such as VAX-A1 whose formulation includes GAS C5a peptidase may have additional benefits through some measure of cross-protection against GBS infections.

Identification of an immunodominant region on a group A Streptococcus T-antigen reveals temperature-dependent motion in pili

Group A Streptococcus (GAS) is a globally important pathogen causing a broad range of human diseases. GAS pili are elongated proteins with a backbone comprised repeating T-antigen subunits, which extend from the cell surface and have important roles in adhesion and establishing infection. No GAS vaccines are currently available, but T-antigen-based candidates are in pre-clinical development. This study investigated antibody-T-antigen interactions to gain molecular insight into functional antibody responses to GAS pili. Large, chimeric mouse/human Fab-phage libraries generated from mice vaccinated with the complete T18.1 pilus were screened against recombinant T18.1, a representative two-domain T-antigen. Of the two Fab identified for further characterization, one (designated E3) was cross-reactive and also recognized T3.2 and T13, while the other (H3) was type-specific reacting with only T18.1/T18.2 within a T-antigen panel representative of the major GAS T-types. The epitopes for the two Fab, determined by x-ray crystallography and peptide tiling, overlapped and mapped to the N-terminal region of the T18.1 N-domain. This region is predicted to be buried in the polymerized pilus by the C-domain of the next T-antigen subunit. However, flow cytometry and opsonophagocytic assays showed that these epitopes were accessible in the polymerized pilus at 37°C, though not at lower temperature. This suggests that there is motion within the pilus at physiological temperature, with structural analysis of a covalently linked T18.1 dimer indicating "knee-joint" like bending occurs between T-antigen subunits to expose this immunodominant region. This temperature dependent, mechanistic flexing provides new insight into how antibodies interact with T-antigens during infection.

The burden of rheumatic heart disease in the Middle East and North Africa region, 1990-2019

BACKGROUND

Rheumatic heart disease (RHD) is a treatable and preventable condition resulting from acute rheumatic fever.

AIM

To report the prevalence, mortality and disability-adjusted life-years (DALY) due to RHD in the Middle East and North Africa (MENA) region from 1990 to 2019, by sex, age group, country and sociodemographic index (SDI).

METHODS

Information on the prevalence, mortality and DALY associated with RHD were obtained from the Global Burden of Disease Study 2019. Data were gathered for all countries in the MENA region over the period 1990-2019. These data included counts and age-standardized rates per 100,000, accompanied by 95% uncertainty intervals (UIs).

RESULTS

The MENA region had an age-standardized point prevalence of 388.9 per 100,000 in 2019, which was 5.4% higher than in 1990. The annual incidence rate was 1.6, which was 63.4% lower than in 1990. There were 379.4 thousand DALY attributable to RHD in 2019, with an age-standardized rate of 67.1, which was 61.3% lower than in 1990. In 2019, an estimated 7.4 thousand deaths were due to RHD, and the age-standardized death rate was 63.4% lower in 2019 than in 1990. DALY rates rose steadily with increasing age in both males and females. The SDI correlated negatively with the rate of DALY for RHD throughout the study period.

CONCLUSION

The burden of RHD in MENA declined from 1990 to 2019, demonstrating the importance of regularly updating health data and identifying risk factors, and developing effective guidelines on prevention.

A Review of Cardiac Surgical Procedures and Their Outcomes for Paediatric Rheumatic Heart Disease in Western Australia

INTRODUCTION

Surgical intervention is an important treatment modality for advanced rheumatic heart disease (RHD). This study aimed to describe patient characteristics and outcomes from cardiac surgery for RHD in patients referred to the only tertiary paediatric hospital in Western Australia.

METHODS

An analysis of patient characteristics and cardiac surgery outcomes in patients with RHD was undertaken, using data from clinical cardiac databases, medical notes, and correspondence from rural outreach clinics.

RESULTS

29 patients (59% female, 97% Aboriginal, Māori or Pacific Islander) underwent 41 valve interventions over 34 cardiac surgeries for RHD between 2000-2018. Median age at first surgery was 12.2 (range 4-16) years. Severe mitral regurgitation (MR) was the most common indication for primary surgery (62%), followed by mixed mitral regurgitation/aortic regurgitation (21%) and severe aortic regurgitation (17%). Mitral valve repair was the most common valve intervention (56%). Two patients had mitral valve replacement (MVR) at first operation, two patients had MVR at second operation and two had MVR at third operation. There was no early mortality. One patient required early (<30 days) reoperation for aortic valve repair failure. Two patients had late reoperations at 3.3 and 6.1 months after the first procedure for MR. Four (14%) patients experienced documented ARF recurrences. Late mortality occurred in 3 (10%) patients, all due to cardiac causes. On last follow-up echocardiogram 5 patients (17%) had moderate MR and none had severe MR.

CONCLUSIONS

This is the first study to describe characteristics and outcomes in WA paediatric patients having surgery for RHD. Outcomes are comparable to similar studies, with favourable long-term survival.

Evaluating the implementation of a dynamic digital application to enable community-based decentralisation of rheumatic heart disease case management in Uganda: protocol for a hybrid type III effectiveness-implementation study

INTRODUCTION

Rheumatic heart disease (RHD) affects over 39 million people worldwide, the majority in low-income and middle-income countries. Secondary antibiotic prophylaxis (SAP), given every 3-4 weeks can improve outcomes, provided more than 80% of doses are received. Poor adherence is strongly correlated with the distance travelled to receive prophylaxis. Decentralising RHD care has the potential to bridge these gaps and at least maintain or potentially increase RHD prophylaxis uptake. A package of implementation strategies was developed with the aim of reducing barriers to optimum SAP uptake.

METHODS AND ANALYSIS

A hybrid implementation-effectiveness study type III was designed to evaluate the effectiveness of a package of implementation strategies including a digital, cloud-based application to support decentralised RHD care, integrated into the public healthcare system in Uganda. Our overarching hypothesis is that secondary prophylaxis adherence can be maintained or improved via a decentralisation strategy, compared with the centralised delivery strategy, by increasing retention in care. To evaluate this, eligible patients with RHD irrespective of their age enrolled at Lira and Gulu hospital registry sites will be consented for decentralised care at their nearest participating health centre. We estimated a sample size of 150-200 registrants. The primary outcome will be adherence to secondary prophylaxis while detailed implementation measures will be collected to understand barriers and facilitators to decentralisation, digital application tool adoption and ultimately its use and scale-up in the public healthcare system.

ETHICS AND DISSEMINATION

This study was approved by the Institutional Review Board (IRB) at Cincinnati Children's Hospital Medical Center (IRB 2021-0160) and Makerere University School of Medicine Research Ethics Committee (Mak-SOMREC-2021-61). Participation will be voluntary and informed consent or assent (>8 but <18) will be obtained prior to participation. At completion, study findings will be communicated to the public, key stakeholders and submitted for publication.

Analysis and comparison of the trends in burden of rheumatic heart disease in China and worldwide from 1990 to 2019

OBJECTIVES

This study aimed to describe the temporal trends in age and gender burdens of rheumatic heart disease (RHD) in China from 1990 to 2019, including incidence, prevalence, mortality, and disability-adjusted life years (DALYs), and to compare them with the global burden of the disease.

METHODS

Using open data from the Global Burden of Disease (GBD) database from 1990 to 2019, this study analyzed the characteristics of RHD burden in China and worldwide, including changes in incidence, prevalence, mortality, and DALYs. Joinpoint was used to calculate the average annual percentage change (AAPC) and the corresponding 95% confidence interval (95% CI) to reflect the trends in the burden of RHD. A comprehensive comparative analysis of the differences in RHD burden between China and the rest of the world was conducted from multiple dimensions, including age, gender, and time periods.

RESULTS

From 1990 to 2019, the age-standardized incidence rate (ASIR) of RHD in China decreased from 29.62/100,000 to 23.95/100,000, while the global ASIR increased from 32.69/100,000 to 37.40/100,000. The age-standardized prevalence rate (ASPR) in China decreased from 446.15/100,000 to 390.24/100,000, while the global ASPR increased from 451.56/100,000 to 513.68/100,000. The age-standardized rates of mortality (ASMR) in China decreased from 18.11/100,000 to 4.04/100,000, while the global ASMR decreased from 8.94/100,000 to 3.85/100,000. The age-standardized DALY rate (ASDR) in China decreased from 431.45/100,000 to 93.73/100,000, while the global ASDR decreased from 283.30/100,000 to 132.88/100,000. The AAPC of ASIR, ASPR, ASMR, and ASDR in China was - 0.73%, -0.47%, -5.10%, and - 5.21%, respectively, while the AAPC of the global burden of RHD was 0.48%, 0.45%, -2.87%, and - 2.58%, respectively. The effects of age and gender on the burden of RHD were different. ASIR generally decreased with increasing age, while ASPR increased first and then decreased. ASMR and ASDR increased with increasing age. Women had higher incidence and mortality rates of RHD than men.

CONCLUSION

From 1990 to 2019, the incidence, prevalence, mortality, and DALYs of RHD in China decreased, indicating a relative reduction in the burden of RHD in China. The burden of RHD is age-related, with a higher prevalence observed in the younger population, a peak incidence among young adults, and a higher mortality rate among the elderly population. Women are more susceptible to RHD and have a higher risk of mortality than men. Given China's large population and aging population, RHD remains a significant public health challenge in China.

Research priorities for the primordial prevention of acute rheumatic fever and rheumatic heart disease by modifying the social determinants of health

The social determinants of health (SDH), such as access to income, education, housing and healthcare, strongly shape the occurrence of acute rheumatic fever (ARF) and rheumatic heart disease (RHD) at the household, community and national levels. The SDH are systemic factors that privilege some more than others and result in poverty and inequitable access to resources to support health and well-being. Primordial prevention is the modification of SDH to improve health and reduce the risk of disease acquisition and the subsequent progression to RHD. Modifying these determinants using primordial prevention strategies can reduce the risk of exposure to Group A Streptococcus, a causative agent of throat and skin infections, thereby lowering the risk of initiating ARF and its subsequent progression to RHD.This report summarises the findings of the Primordial Prevention Working Group-SDH, which was convened in November 2021 by the National Heart, Lung, and Blood Institute to assess how SDH influence the risk of developing RHD. Working group members identified a series of knowledge gaps and proposed research priorities, while recognising that community engagement and partnerships with those with lived experience will be integral to the success of these activities. Specifically, members emphasised the need for: (1) global analysis of disease incidence, prevalence and SDH characteristics concurrently to inform policy and interventions, (2) global assessment of legacy primordial prevention programmes to help inform the co-design of interventions alongside affected communities, (3) research to develop, implement and evaluate scalable primordial prevention interventions in diverse settings and (4) research to improve access to and equity of services across the RHD continuum. Addressing SDH, through the implementation of primordial prevention strategies, could have broader implications, not only improving RHD-related health outcomes but also impacting other neglected diseases in low-resource settings.

Research priorities for the secondary prevention and management of acute rheumatic fever and rheumatic heart disease: a National Heart, Lung, and Blood Institute workshop report

Secondary prevention of acute rheumatic fever (ARF) and rheumatic heart disease (RHD) involves continuous antimicrobial prophylaxis among affected individuals and is recognised as a cornerstone of public health programmes that address these conditions. However, several important scientific issues around the secondary prevention paradigm remain unresolved. This report details research priorities for secondary prevention that were developed as part of a workshop convened by the US National Heart, Lung, and Blood Institute in November 2021. These span basic, translational, clinical and population science research disciplines and are built on four pillars. First, we need a better understanding of RHD epidemiology to guide programmes, policies, and clinical and public health practice. Second, we need better strategies to find and diagnose people affected by ARF and RHD. Third, we urgently need better tools to manage acute RF and slow the progression of RHD. Fourth, new and existing technologies for these conditions need to be better integrated into healthcare systems. We intend for this document to be a reference point for research organisations and research sponsors interested in contributing to the growing scientific community focused on RHD prevention and control.

Development and User Testing of a Dynamic Tool for Rheumatic Heart Disease Management

OBJECTIVE

Most rheumatic heart disease (RHD) registries are static and centralized, collecting epidemiological and clinical data without providing tools to improve care. We developed a dynamic cloud-based RHD case management application with the goal of improving care for patients with RHD in Uganda.

METHODS

The Active Community Case Management Tool (ACT) was designed to improve community-based case management for chronic disease, with RHD as the first test case. Global and local partner consultation informed selection of critical data fields and prioritization of application functionality. Multiple stages of review and revision culminated in user testing of the application at the Uganda Heart Institute.

RESULTS

Global and local partners provided feedback of the application via survey and interview. The application was well received, and top considerations included avenues to import existing patient data, considering a minimum data entry form, and performing a situation assessment to tailor ACT to the health system setup for each new country. Test users completed a postuse survey. Responses were favorable regarding ease of use, desire to use the application in regular practice, and ability of the application to improve RHD care in Uganda. Concerns included appropriate technical skills and supports and potential disruption of workflow.

CONCLUSION

Creating the ACT application was a dynamic process, incorporating iterative feedback from local and global partners. Results of the user testing will help refine and optimize the application. The ACT application showed potential for utility and integration into existing care models in Uganda.

Left ventricular remodelling in rheumatic heart disease - trends over time and implications for follow-up in childhood

BACKGROUND

Rheumatic heart disease (RHD) is the most common form of acquired heart disease worldwide. In RHD, volume loading from mitral regurgitation leads to left ventricular (LV) dilatation, increased wall stress, and ultimately LV dysfunction. Improved understanding of LV dynamics may contribute to refined timing of intervention. We aimed to characterize and compare left ventricular remodelling between rheumatic heart disease (RHD) severity groups by way of serial echocardiographic assessment of volumes and function in children.

METHODS

Children with RHD referred to Perth Children's Hospital (formally Princess Margaret Hospital) (1987-2020) were reviewed. Patients with longitudinal pre-operative echocardiograms at diagnosis, approximately 12 months and at most recent follow-up, were included and stratified into RHD severity groups. Left ventricular (LV) echocardiographic parameters were assessed. Adjusted linear mixed effect models were used to compare interval changes.

RESULTS

146 patients (median age 10 years, IQR 6-14 years) with available longitudinal echocardiograms were analysed. Eighty-five (58.2%) patients had mild, 33 (22.6%) moderate and 28 (19.2%) severe RHD at diagnosis. Mean duration of follow-up was 4.6 years from the initial diagnosis. Severe RHD patients had significantly increased end-systolic volumes (ESV) and end-diastolic volumes (EDV) compared to mild/moderate groups at diagnosis (severe versus mild EDV mean difference 27.05 ml/m2, p < 0.001, severe versus moderate EDV mean difference 14.95 ml/m2, p = 0.006). Mild and moderate groups experienced no significant progression of changes in volume measures. In severe RHD, LV dilatation worsened over time. All groups had preserved cardiac function.

CONCLUSIONS

In mild and moderate RHD, the lack of progression of valvular regurgitation and ventricular dimensions suggest a stable longer-term course. Significant LV remodelling occurred at baseline in severe RHD with progression of LV dilatation over time. LV function was preserved across all groups. Our findings may guide clinicians in deciding the frequency and timing of follow-up and may be of clinical utility during further reiterations of the Australia and New Zealand RHD Guidelines.

Health Related Quality of Life and Associated Factors Among Adult Patients with Rheumatic Heart Disease Patients in Ethiopia

Background

Quality of life (QOL) is defined as "individuals" perceptions of their position in life. Rheumatic heart disease (RHD) is a consequence of severe, single, or recurrent bouts of acute rheumatic fever. To improve overall patient outcomes, there is currently a greater emphasis on assessing the QOL of these patients. The purpose of this study is to assess the QOL of adult RHD patients who had followed up at St Peter and Tikur Anbessa Hospital, Ethiopia.

Methods

An institutional-based cross-sectional study done at St Peter and Tikur Anbessa Hospital, Ethiopia from March 1-June 30/2021 in adult RHD patients. The sample size was 297. Socio-demographic and clinical data were collected using a structured questionnaire. The Amharic version of Short form-36 (SF-36) was used to assess the QOL. A logistic regression model was used to identify associated factors.

Results

The study included 297 patients. The majority are female (71%), and half of them are aged between 18-30 years of age. Of the patiends, 81.1% had no comorbidity, and 15.8% had interventions. RHD affects all domains and summary scores of short form 36 QOL parameters compared to normative values. Age, marital status, place of residence, presence of comorbidity, number of medications, and whether an intervention was done are associated with the QOL of these patients.

Conclusion

RHD patients had poor QOL assessed by SF-36. It affects all domains and summary score of short form 36 QOL parameters. Old age, divorce, living in rural areas, associated comorbid conditions, and no intervention done are associated with poor QOL. Identification and treating comorbid conditions and intervention may improve QOL.

Spatiotemporal trends in global burden of rheumatic heart disease and associated risk factors from 1990 to 2019

BACKGROUND

The aim of this study was to estimate the burden of rheumatic heart disease (RHD) and its trends in different countries, regions, genders and age groups globally.

METHODS

Data were obtained from the Global Burden of Disease 2019 study. Age-standardized rates (ASRs) and the estimated annual percentage changes (EAPCs) in the ASRs were used to describe the burden of disease and its trends. Pearson's correlation was used to evaluate the correlation between sociodemographic index (SDI) values and the observed trends.

RESULTS

In 2019, the ASRs of the incidence, prevalence, mortality and disability-adjusted life years (DALYs) of RHD were 37.39/105 (95%UI, 28.59/105 to 46.74/105), 513.68/105 (95%UI, 405.01/105 to 636.25/105), 3.85/105 (95%UI, 4.29/105 to 3.29/105) and 132.88/105 (95%UI, 115.02/105 to 150.34/105), respectively. From 1990 to 2019, the incidence and prevalence of RHD showed upward trends and the mortality and DALYs showed downward trends. Countries or regions in Africa, South America and South Asia had a greater burden of RHD. The burden of RHD was greater in women, where as men showed more obvious increasing trends in the incidence and prevalence. The incidence of RHD was highest in adolescents, and the prevalence was highest in young and middle-aged. The mortality and DALYs rate associated with RHD increased with age. The EAPCs in the ASRs were negatively correlated with the SDI value.

CONCLUSION

Although the ASRs of mortality and DALYs attributable to RHD are decreasing globally, RHD remains an important public health problem that needs to be addressed urgently, especially in certain low- and middle-income countries and regions.

A conserved 3D pattern in a Streptococcus pyogenes M protein immunogen elicits M-type crossreactivity

Coiled coil-forming M proteins of the widespread and potentially deadly bacterial pathogen Streptococcus pyogenes (strep A) are immunodominant targets of opsonizing antibodies. However, antigenic sequence variability of M proteins into >220 M types, as defined by their hypervariable regions (HVRs), is considered to limit M proteins as vaccine immunogens because of type specificity in the antibody response. Surprisingly, a multi-HVR immunogen in clinical vaccine trials was shown to elicit M-type crossreactivity. The basis for this crossreactivity is unknown but may be due in part to antibody recognition of a 3D pattern conserved in many M protein HVRs that confers binding to human complement C4b-binding protein (C4BP). To test this hypothesis, we investigated whether a single M protein immunogen carrying the 3D pattern would elicit crossreactivity against other M types carrying the 3D pattern. We found that a 34-amino acid sequence of S. pyogenes M2 protein bearing the 3D pattern retained full C4BP-binding capacity when fused to a coiled coil-stabilizing sequence from the protein GCN4. We show that this immunogen, called M2G, elicited cross-reactive antibodies against a number of M types that carry the 3D pattern but not against those that lack the 3D pattern. We further show that the M2G antiserum-recognized M proteins displayed natively on the strep A surface and promoted the opsonophagocytic killing of strep A strains expressing these M proteins. As C4BP binding is a conserved virulence trait of strep A, we propose that targeting the 3D pattern may prove advantageous in vaccine design.

Serum endocan levels in children with rheumatic aortic insufficiency: can it differentiate bicuspid aortic valve disease from rheumatic heart disease?

AIM

In this study, it was aimed to examine the serum endocan levels in patients with rheumatic aortic regurgitation and to investigate whether it has a value in differentiating it from aortic regurgitation due to bicuspid aortic valve.

METHODS

Blood samples were collected from patients with rheumatic aortic regurgitation (Group 1), incidentally diagnosed patients with borderline or definite rheumatic aortic regurgitation (Group 2), children with bicuspid aortic valve accompanied by aortic regurgitation (Group 3) and healthy children (Group 4) of similar age.

RESULTS

There were 12 children in Group 1, 13 in Group 2, 25 in Group 3, and 25 in Group 4. Groups were similar in terms of age (p = 0.291). There was no statistically significant difference between median serum endocan levels of Group 1 and Group 2 (p = 0.624), and Group 3 and Group 4 (p = 0.443). Despite that, the median serum endocan levels of Group 1 and Group 2 were significantly higher than that of both Group 3 and Group 4 (p = 0.000 for all).

CONCLUSIONS

Our results indicate that serum endocan level can be used to differentiate rheumatic aortic regurgitation from non-rheumatic aortic regurgitation. It is thought that the prognostic role of this marker should be confirmed in long-term, prospective studies with larger samples.

Three-dimensional transoesophageal echocardiography: how to use and when to use-a clinical consensus statement from the European Association of Cardiovascular Imaging of the European Society of Cardiology

Three-dimensional transoesophageal echocardiography (3D TOE) has been rapidly developed in the last 15 years. Currently, 3D TOE is particularly useful as an additional imaging modality for the cardiac echocardiographers in the echo-lab, for cardiac interventionalists as a tool to guide complex catheter-based procedures cardiac, for surgeons to plan surgical strategies, and for cardiac anaesthesiologists and/or cardiologists, to assess intra-operative results. The authors of this document believe that acquiring 3D data set should become a 'standard part' of the TOE examination. This document provides (i) a basic understanding of the physic of 3D TOE technology which enables the echocardiographer to obtain new skills necessary to acquire, manipulate, and interpret 3D data sets, (ii) a description of valvular pathologies, and (iii) a description of non-valvular pathologies in which 3D TOE has shown to be a diagnostic tool particularly valuable. This document has a new format: instead of figures randomly positioned through the text, it has been organized in tables which include figures. We believe that this arrangement makes easier the lecture by clinical cardiologists and practising echocardiographers.

Myocardial fibrosis in rheumatic heart disease: emerging concepts and clinical implications

Rheumatic heart disease (RHD) remains a significant cardiovascular burden in the world even though it is no longer common in affluent countries. Centuries of history surrounding this disease provide us with a thorough understanding of its pathophysiology. Infections in the throat, skin, or mucosa are the gateway for Group A Streptococcus (GAS) to penetrate our immune system. A significant inflammatory response to the heart is caused by an immunologic cascade triggered by GAS antigen cross-reactivity. This exaggerated immune response is primarily responsible for cardiac dysfunction. Recurrent inflammatory processes damage all layers of the heart, including the endocardium, myocardium, and pericardium. A vicious immunological cycle involving inflammatory mediators, angiotensin II, and TGF-β promotes extracellular matrix remodeling, resulting in myocardial fibrosis. Myocardial fibrosis appears to be a prevalent occurrence in patients with RHD. The presence of myocardial fibrosis, which causes left ventricular dysfunction in RHD, might be utilized to determine options for treatment and might also be used to predict the outcome of interventions in patients with RHD. This emerging concept of myocardial fibrosis needs to be explored comprehensively in order to be optimally utilized in the treatment of RHD.

Molecular Mimicry Mapping in Streptococcus pneumoniae: Cues for Autoimmune Disorders and Implications for Immune Defense Activation

Streptococcus pneumoniae contributes to a range of infections, including meningitis, pneumonia, otitis media, and sepsis. Infections by this bacterium have been associated with the phenomenon of molecular mimicry, which, in turn, may contribute to the induction of autoimmunity. In this study, we utilized a bioinformatics approach to investigate the potential for S. pneumoniae to incite autoimmunity via molecular mimicry. We identified 13 S. pneumoniae proteins that have significant sequence similarity to human proteins, with 11 of them linked to autoimmune disorders such as psoriasis, rheumatoid arthritis, and diabetes. Using in silico tools, we predicted the sequence as well as the structural homology among these proteins. Database mining was conducted to establish links between these proteins and autoimmune disorders. The antigenic, non-allergenic, and immunogenic sequence mimics were employed to design and validate an immune response via vaccine construct design. Mimic-based vaccine construct can prove effective for immunization against the S. pneumoniae infections. Immune response simulation and binding affinity was assessed through the docking of construct C8 to human leukocyte antigen (HLA) molecules and TLR4 receptor, with promising results. Additionally, these mimics were mapped as conserved regions on their respective proteins, suggesting their functional importance in S. pneumoniae pathogenesis. This study highlights the potential for S. pneumoniae to trigger autoimmunity via molecular mimicry and the possibility of vaccine design using these mimics for triggering defense response.

The rise and fall of acute rheumatic fever and rheumatic heart disease: a mini review

Introduction

The incidences of acute rheumatic fever (ARF) and rheumatic heart disease (RHD), which were leading causes of death in children in the 1920s, have decreased substantially. Considering the recent resurgence of scarlet fever and increased incidence of streptococcal pharyngitis in children, an investigation of the current status of ARF and RHD may be worthwhile.

Objective

To summarize the prevalence trends, pathogenic factors, and prevention strategies for ARF and RHD in children.

Methods

A selective search of literature published between January 1920 and February 2023 was done in PubMed, using the terms "acute rheumatic fever", "rheumatic heart disease", "group A Streptococcus", "pharyngitis", "pharyngeal tonsillitis", "scarlet fever", "impetigo", "obstructive sleep apnea syndrome" and "child".

Results

Overcrowded homes and inadequate sanitation led to recurrent group A streptococcal infection, and the causal relationship between group A streptococcal infection and ARF/RHD was well established. Streptococcal infectious diseases, such as group A streptococcal pharyngeal tonsillitis, SF, impetigo, and obstructive sleep apnea syndrome, were associated with the occurrence of ARF and RHD. ARF and RHD were still prevalent in young people of developing countries and economically poor populations of high-income countries. Universal disease registration systems were critical to locating disease outbreaks, tracking disease transmission, and identifying high-risk populations. Four-level prevention strategies were effective in reducing the incidence and mortality of ARF and RHD.

Conclusions

Registry and preventive measures for ARF and RHD should be strengthened in areas of dense population; poor sanitation; resurgence of SF; and high incidence of streptococcal pharyngitis, impetigo, and obstructive sleep apnea syndrome.

The microbiome and rheumatic heart disease: current knowledge and future perspectives

Rheumatic heart disease (RHD) is a cardiovascular disease caused by an autoimmune response to group A Streptococcus (GAS) infection resulting in the damage of heart valves. RHD is the most commonly acquired heart disease among children and young adults with a global burden of over 40 million cases accounting for 306,000 deaths annually. Inflammation in the heart valves caused due to molecular mimicry between the GAS antigens and host cardiac proteins is facilitated by cytokines, cross-reactive antibodies and CD4⁺ T cells. The complex interaction between genetic and environmental factors linked with erratic events leads to the loss of immunological tolerance and autoimmunity in RHD. Despite extensive research on the etiopathogenesis of RHD, the precise mechanism underpinning the initiation of acute rheumatic fever (ARF) to the progression of RHD still remains elusive. Mounting evidences support the contribution of the human microbiome in the development of several immune-mediated diseases including rheumatoid arthritis, juvenile idiopathic arthritis, Kawasaki disease, inflammatory bowel disease and type 1 diabetes. The microbiome and their metabolites could play a crucial role in the integrity of the epithelial barrier, development of the immune system, inflammation and differentiation of T cell subsets. Consequently, microbiome dysbiosis might result in autoimmunity by molecular mimicry, epitope spreading and bystander activation. This review discusses various aspects of the interaction between the microbiome and the immune system in order to reveal causative links relating dysbiosis and autoimmune diseases with special emphasis on RHD.

The global burden and trends of four major types of heart disease, 1990-2019: a systematic analysis for the Global Burden of Disease Study 2019

OBJECTIVES

The global burden of heart disease is severe and increasing in the coming years. This study aims to analyze the global burden of heart disease.

STUDY DESIGN

Rheumatic heart disease (RHD), ischemic heart disease (IHD), hypertensive heart disease (HHD), and non-rheumatic valvular heart disease (NRVHD) were selected and analyzed from the Global Burden of Disease Study 2019.

METHODS

The prevalence, deaths, disability-adjusted life years and their corresponding age-standardized rates were obtained from the Global Burden of Disease Study 2019. In addition, estimated annual percentage change was calculated to better assess epidemiological trends. In addition, we performed an age-period-cohort analysis using the Nordpred package in R program to predict death trends over the next 20 years.

RESULTS

Globally, the prevalence of four heart diseases (RHD, IHD, HHD, and NRVHD) increased by 70.5%, 103.5%, 137.9%, and 110.0% compared with 1990, respectively. The deaths cases of RHD decreased by 15.6%, whereas IHD, HHD, and NRVHD increased by 60.4%, 76.6%, and 110.6%. Compared with absolute values, their corresponding age-standardized rates only showed a slight increase trend or even decreased in some areas with high sociodemographic index. In the next 20 years, the absolute values of deaths will continue to increase, whereas their age-standardized rates of deaths will flatten out.

CONCLUSIONS

Globally, the absolute values of heart disease have increased over the past 30 years and will continue to increase over the next 20 years. Targeted prevention and control strategies and measures need to be developed and improved to reduce this burden.

Positive impact of training rural health workers in identification and prevention of acute rheumatic fever in eastern Uganda

BACKGROUND

Diagnosis of acute rheumatic fever (ARF) is mainly clinical. Delayed or missed diagnosis and failure to administer appropriate and timely treatment of ARF leads to rheumatic heart disease (RHD), which could necessitate expensive treatments such as open-heart surgery. Implementation of preventative guidelines depends on availability of trained healthcare workers. As part of the routine support supervision, the Uganda Heart Institute sent out a team to rural eastern Uganda to evaluate health workers' knowledge level regarding management of ARF.

METHODS

Health workers from selected health facilities in Tororo district, eastern Uganda, were assessed for their knowledge on the clinical features and role of benzathine penicillin G (BPG) in the treatment and prevention of ARF recurrence. Using the RHD Action Needs assessment tool, we generated and administered a pre-test, then conducted training and re-administered a post-test. Eight months later, health workers were again assessed for knowledge retention and change in practices. Statistical analysis was done using Stata version 15.

RESULTS

During the initial phase, 34 of the 109 (31%) health workers passed the pre-test, indicating familiarity with clinical features of ARF. The level of knowledge of BPG use in ARF was very poor in all the health units [25/109 (22.6%)] but improved after training to 80%, as shown by the chi-squared test ( χ2 = 0.000). However, retention of this knowledge waned after eight months and was not significantly different compared to pre-training (χ2 ≥ 0.2).

CONCLUSIONS

A critical knowledge gap is evident among health workers, both in awareness and treatment of ARF, and calls for repetitive training as a priority strategy in prevention.

American Heart Association's Children's Strategically Focused Research Network Experience

The American Heart Association's Strategically Focused Children's Research Network started in July 2017 with 4 unique programs at Children's National Hospital in Washington, DC; Duke University in Durham, North Carolina; University of Utah in Salt Lake City, Utah; and Lurie Children's Hospital/Northwestern University in Chicago, Illinois. The overarching goal of the Children's National center was to develop evidence-based strategies to strengthen the health system response to rheumatic heart disease through synergistic basic, clinical, and population science research. The overall goals of the Duke center were to determine risk factors for obesity and response to treatment including those that might work on a larger scale in communities across the country. The integrating theme of the Utah center focused on leveraging big data-science approaches to improve the quality of care and outcomes for children with congenital heart defects, within the context of the patient and their family. The overarching hypothesis of the Northwestern center is that the early course of change in cardiovascular health, from birth onward, reflects factors that result in either subsequent development of cardiovascular risk or preservation of lifetime favorable cardiovascular health. All 4 centers exceeded the original goals of research productivity, fellow training, and collaboration. This article describes details of these accomplishments and highlights challenges, especially around the COVID-19 pandemic.

A Case Report: Acute Rheumatic Fever or Something More?

Acute rheumatic fever (ARF) is an autoimmune response that may occur after a group A Streptococcus (GAS) infection. Subcutaneous nodules are considered a rare manifestation of acute rheumatic fever with an incidence of 0%-10%. We present a case study of a 13-year-old girl who presented to us with subcutaneous nodules and articular involvement described as a non-migratory polyarticular joint pain involving the small joints of the hands, wrist, elbows, knees, and ankles for three months with poor response to the non-steroidal anti-inflammatory drug (NSAID) Ibuprofen. Accompanied with the presence of carditis, the patient fulfilled three major and two minor criteria of the revised Jones criteria 2015. Therefore, a diagnosis of acute rheumatic fever was made. The child was asymptomatic on subsequent visits, and although the subcutaneous nodules subsided, she will continue to receive penicillin every month for five years. We describe the successful diagnosis and management of a patient with ARF.