Project description:Rheumatic heart disease (RHD) continues to affect developing countries with low income, due to the lack of resources and effective diagnostic techniques. Understanding the genetic basis of progression from its prequel disease state, acute rheumatic fever (ARF), would aid in developing predictive biomarkers and improving patient care. To gain system-wide molecular insights into possible causes for progression, we collected blood transcriptomes from ARF (5) and RHD (5) patients. Using an integrated transcriptome and network analysis, we identified a subnetwork comprising the most significantly differentially expressed genes and most perturbed pathways in RHD as compared to ARF. For example, the chemokine signaling pathway was seen to be upregulated while tryptophan metabolism was found to be downregulated in RHD. The subnetworks of variation between the two conditions provide unbiased molecular-level insights into the host processes that may be associated with the progression of ARF to RHD, which has the potential to inform future diagnostics and therapeutic strategies. We also found significantly raised neutrophil/lymphocyte ratio in both ARF and RHD cohorts. Activated neutrophils and inhibited NK cell gene signatures reflected the drivers of the inflammatory process being common to both the disease conditions.
Project description:BackgroundRheumatic heart disease (RHD) remains a major health concern for Aboriginal Australians. A key component of RHD control is prevention of recurrent acute rheumatic fever (ARF) using long-term secondary prophylaxis with intramuscular benzathine penicillin (BPG). This is the most important and cost-effective step in RHD control. However, there are significant challenges to effective implementation of secondary prophylaxis programs. This project aimed to increase understanding and improve quality of RHD care through development and implementation of a continuous quality improvement (CQI) strategy.MethodsWe used a CQI strategy to promote implementation of national best-practice ARF/RHD management guidelines at primary health care level in Indigenous communities of the Northern Territory (NT), Australia, 2008-2010. Participatory action research methods were employed to identify system barriers to delivery of high quality care. This entailed facilitated discussion with primary care staff aided by a system assessment tool (SAT). Participants were encouraged to develop and implement strategies to overcome identified barriers, including better record-keeping, triage systems and strategies for patient follow-up. To assess performance, clinical records were audited at baseline, then annually for two years. Key performance indicators included proportion of people receiving adequate secondary prophylaxis (≥80% of scheduled 4-weekly penicillin injections) and quality of documentation.ResultsSix health centres participated, servicing approximately 154 people with ARF/RHD. Improvements occurred in indicators of service delivery including proportion of people receiving ≥40% of their scheduled BPG (increasing from 81/116 [70%] at baseline to 84/103 [82%] in year three, p = 0.04), proportion of people reviewed by a doctor within the past two years (112/154 [73%] and 134/156 [86%], p = 0.003), and proportion of people who received influenza vaccination (57/154 [37%] to 86/156 [55%], p = 0.001). However, the proportion receiving ≥80% of scheduled BPG did not change. Documentation in medical files improved: ARF episode documentation increased from 31/55 (56%) to 50/62 (81%) (p = 0.004), and RHD risk category documentation from 87/154 (56%) to 103/145 (76%) (p < 0.001). Large differences in performance were noted between health centres, reflected to some extent in SAT scores.ConclusionsA CQI process using a systems approach and participatory action research methodology can significantly improve delivery of ARF/RHD care.
Project description:Nearly a century after rheumatic fever (RF) and rheumatic heart disease (RHD) was eradicated from the developed world, the disease remains endemic in many low- and middle-income countries (LMICs), with grim health and socioeconomic impacts. The neglect of RHD which persisted for a semi-centennial was further driven by competing infectious diseases, particularly the human immunodeficiency virus (HIV) pandemic. However, over the last two-decades, slowly at first but with building momentum, there has been a resurgence of interest in RF/RHD. In this narrative review, we present the advances that have been made in the RF/RHD continuum over the past two decades since the re-awakening of interest, with a more concise focus on the last decade's achievements. Such primary advances include understanding the genetic predisposition to RHD, group A Streptococcus (GAS) vaccine development, and improved diagnostic strategies for GAS pharyngitis. Echocardiographic screening for RHD has been a major advance which has unearthed the prevailing high burden of RHD and the recent demonstration of benefit of secondary antibiotic prophylaxis on halting progression of latent RHD is a major step forward. Multiple befitting advances in tertiary management of RHD have also been realized. Finally, we summarize the research gaps and provide illumination on profitable future directions towards global eradication of RHD.
Project description:BackgroundIn Victoria, Australia, children with Pacific Islander ('Pacific') ethnicities are overrepresented in acute rheumatic fever (ARF) and rheumatic heart disease (RHD). In June 2023, ARF and RHD became notifiable in Victoria. To inform public health and clinical practice, we described young Pacific patients' and their caregivers' understandings and experiences of ARF/RHD, and identified possible ways to improve the delivery of clinical care.MethodsWe established a project reference group including local Pacific people to guide this research. Pacific patients who attended an ARF/RHD clinic at The Royal Children's Hospital, Melbourne, were invited to participate, as were their caregivers. A Samoan researcher conducted qualitative 'talanoa' (conversational) interviews with patients and caregivers. A second researcher conducted semi-structured interviews with treating clinicians and other stakeholders. Interview transcripts underwent thematic analysis guided by the Tuilaepa Youth Mentoring Services Pacific Youth Wellbeing Framework.ResultsWe interviewed 27 participants. This included nine patients and nine caregivers, all of whom were Samoan. These 18 participants expressed a desire to learn more about ARF/RHD and connect with other affected people. While some shared their experiences of having well-liked and trusted healthcare providers, patients often struggled to have two-way clinical conversations. The need to support clinicians working with high-risk populations to improve their awareness of ARF was identified. Receiving treatment on time was a top priority for affected families, despite injection pain, inconvenience and financial costs. The need to support continuity of care for young adult patients was raised by participants.ConclusionsPacific people living with ARF/RHD and their families require additional support to receive high quality management in Victoria. Introducing a patient register and a specialist RHD nurse would enhance access to treatment, as would removing cost barriers, improving clinical awareness of ARF/RHD and creating Victoria-specific patient resources.
Project description:Background & objectivesRheumatic fever (RF) and rheumatic heart disease (RHD) are the autoimmune sequelae caused by Group A Streptococcus. RHD still remains a major concern in the developing countries due to its poor diagnosis, lack of vaccines and social awareness among population. This study was aimed to identify the plausible early- and late-stage disease markers associated with RF/RHD.MethodsA total of 84 patients with confirmed pharyngitis (n=18), RF (n=23) and RHD (n=43) were included in the comparative analysis of different factors involved in host-pathogen interaction during RF/RHD pathogenesis.ResultsThis study revealed high titre of serum antistreptolysin O (ASO) antibody in pharyngitis compared to RF and RHD patients, whereas procollagen type 1 C-peptide (PICP) level was elevated in RHD which showed an inverse correlation with serum ASO titre. The significant elevation of serum anti-peptide associated with RF (PARF) antibody in RF patients was correlated as a probable stage-specific determinant. In addition, pro-inflammatory cytokine profile revealed high levels of interleukin-12 (IL-12)/IL-23p40, IL-17A in RF, whereas IL-6 concentration was higher in RHD compared to healthy controls.Interpretation & conclusionsThe overall assessment of the factors/ disease markers involved in host-pathogen interaction in RF/RHD may be suggestive of plausible disease marker in different groups of patients. Further studies with larger sample need to be done to better understand RF/RHD pathogenesis.
Project description:BackgroundAcute rheumatic fever (ARF) is a serious sequela of Group A Streptococcus (GAS) infection associated with significant global mortality. Pathogenesis remains poorly understood, with the current prevailing hypothesis based on molecular mimicry and the notion that antibodies generated in response to GAS infection cross-react with cardiac proteins such as myosin. Contemporary investigations of the broader autoantibody response in ARF are needed to both inform pathogenesis models and identify new biomarkers for the disease.MethodsThis study has utilised a multi-platform approach to profile circulating autoantibodies in ARF. Sera from patients with ARF, matched healthy controls and patients with uncomplicated GAS pharyngitis were initially analysed for autoreactivity using high content protein arrays (Protoarray, 9000 autoantigens), and further explored using a second protein array platform (HuProt Array, 16,000 autoantigens) and 2-D gel electrophoresis of heart tissue combined with mass spectrometry. Selected autoantigens were orthogonally validated using conventional immunoassays with sera from an ARF case-control study (n=79 cases and n=89 matched healthy controls) and a related study of GAS pharyngitis (n=39) conducted in New Zealand.ResultsGlobal analysis of the protein array data showed an increase in total autoantigen reactivity in ARF patients compared with controls, as well as marked heterogeneity in the autoantibody profiles between ARF patients. Autoantigens previously implicated in ARF pathogenesis, such as myosin and collagens were detected, as were novel candidates. Disease pathway analysis revealed several autoantigens within pathways linked to arthritic and myocardial disease. Orthogonal validation of three novel autoantigens (PTPN2, DMD and ANXA6) showed significant elevation of serum antibodies in ARF (p < 0.05), and further highlighted heterogeneity with patients reactive to different combinations of the three antigens.ConclusionsThe broad yet heterogenous elevation of autoantibodies observed suggests epitope spreading, and an expansion of the autoantibody repertoire, likely plays a key role in ARF pathogenesis and disease progression. Multiple autoantigens may be needed as diagnostic biomarkers to capture this heterogeneity.
Project description:BackgroundAcute rheumatic fever is a systemic inflammatory condition caused by beta-hemolytic streptococcal infection. Its prevalence in high-income countries has fallen significantly as a result of widespread antibiotic use and improved living conditions.Case summaryWe report the case of an 18-year-old, otherwise healthy, Irish woman who presented to an Irish hospital with fever and general malaise on a background of recurrent pharyngitis. Her condition rapidly deteriorated in the hospital and she developed septic shock requiring intensive care admission for organ support. Investigations confirmed pancarditis secondary to acute rheumatic fever, which was ultimately treated with antibiotics and corticosteroids.DiscussionThis case highlights that acute rheumatic fever can present with multiple nonspecific symptoms, in unexpected populations, including in the developed world. Early diagnosis and treatment initiation of antimicrobial therapy and corticosteroids is imperative for optimal overall outcomes in rheumatic heart disease.
Project description:Acute rheumatic fever (ARF) is a multiorgan inflammatory disorder that results from the body's autoimmune response to pharyngitis or a skin infection caused by Streptococcus pyogenes (Strep A). Acute rheumatic fever mainly affects those in low- and middle-income nations, as well as in indigenous populations in wealthy nations, where initial Strep A infections may go undetected. A single episode of ARF puts a person at increased risk of developing long-term cardiac damage known as rheumatic heart disease. We present case definitions for both definite and possible ARF, including initial and recurrent episodes, according to the 2015 Jones Criteria, and we discuss current tests available to aid in the diagnosis. We outline the considerations specific to ARF surveillance methodology, including discussion on where and how to conduct active or passive surveillance (eg, early childhood centers/schools, households, primary healthcare, administrative database review), participant eligibility, and the surveillance population. Additional considerations for ARF surveillance, including implications for secondary prophylaxis and follow-up, ARF registers, community engagement, and the impact of surveillance, are addressed. Finally, the core elements of case report forms for ARF, monitoring and audit requirements, quality control and assurance, and the ethics of conducting surveillance are discussed.