Surviving Postpartum Group A Streptococcus Sepsis Complicated by Multiorgan System Failure: A Complex Case Presentation

Postpartum group A streptococcal (GAS) sepsis is a rare obstetric complication with severe clinical implications and high morbidity and mortality, presenting diagnostic and management challenges. This report analyzes a complex case of postpartum GAS sepsis, highlighting the importance of understanding the pathophysiology and clinical trajectories of this often fatal pathogen. A comprehensive analysis was conducted on a patient with postpartum GAS sepsis. Literature review and case comparisons informed the study's context. Medical history, clinical presentation, diagnostic procedures, interventions, and outcomes were reviewed and documented. The patient presented on postpartum day 5 with abdominal pain and vaginal bleeding. Her condition rapidly deteriorated, requiring aggressive interventions and systemic support. Blood cultures confirmed GAS bacteremia. She developed toxic shock syndrome, cardiomyopathy with acute cardiac failure, and seizures secondary to subdural empyema. Multidisciplinary care facilitated eventual clinical recovery. Obstacles in achieving treatment balance were evident, underscoring the systemic nature of GAS infection and the significance of interdisciplinary collaboration. This case underscores the complex pathophysiology of postpartum GAS sepsis and the importance of prompt treatment initiation, aggressive intervention, and a multidisciplinary approach to management. The study contributes to the understanding of disease progression and clinical management in severe peripartum infections, reaffirming the need for further research to improve outcomes.

Group A Streptococcus interactions with the host across time and space

Group A Streptococcus (GAS) has a fantastically wide tissue tropism in humans, manifesting as different diseases depending on the strain's virulence factor repertoire and the tissue involved. Activation of immune cells and pro-inflammatory signaling has historically been considered an exclusively host-protective response that a pathogen would seek to avoid. However, recent advances in human and animal models suggest that in some tissues, GAS will activate and manipulate specific pro-inflammatory pathways to promote growth, nutrient acquisition, persistence, recurrent infection, competition with other microbial species, dissemination, and transmission. This review discusses molecular interactions between the host and pathogen to summarize how infection varies across tissue and stages of inflammation. A need for inflammation for GAS survival during common, mild infections may drive selection for mechanisms that cause pathological and excess inflammation severe diseases such as toxic shock syndrome, necrotizing fasciitis, and rheumatic heart disease.

A Longitudinal Study of Group A Streptococcal Colonization and Pharyngitis in US Children

BACKGROUND

Group A streptococci (GAS) are a major cause of pharyngitis in children. Recently, there were severe GAS outbreaks. The aims of this study were to assess pharyngeal colonization prevalence in healthy children, to assess different diagnostic definitions for GAS pharyngitis and to estimate incidence rates for these infections.

METHODS

A 2-year longitudinal study was conducted in healthy children in the United States. Pharyngeal swabs were cultured every 3 months for GAS colonization. Serum antistreptolysin O, antideoxyribonuclease B (DNaseB) and antistreptococcal C5a peptidase (SCP) antibody titers were assessed at baseline. When participants developed a sore throat, pharyngeal swabs were collected for rapid antigen detection test (RADT) and culture, and antibody titers were determined in serum samples. A range of case definitions were used for GAS pharyngitis.

RESULTS

A total of 422 children 3-12 years old were enrolled (140, 141 and 141 were 3-5, 6-9 and 10-12 years of age, respectively). The overall prevalence of GAS colonization during the study was 48%. Baseline antistreptolysin O, anti-DNaseB and anti-SCP antibody titers were higher for children older than 5 years. The incidence of GAS pharyngitis per 100 person-years was 15.9 for RADT/culture-proven and 4.6 for serologically confirmed pharyngitis.

CONCLUSIONS

GAS throat colonization and pharyngitis were frequent in children 3-12 years old. The case definition employed impacted the measured incidence of GAS pharyngitis, with higher rates detected using RADT/culture-based definitions. These data suggest that case definition is important and that young children are exposed to GAS, which may inform plans for vaccine development and implementation.

Diagnostic Accuracy of Group A Streptococcus Rapid Antigen Detection Test on Middle Ear Fluid in Children With Acute Otitis Media With Spontaneous Perforation: A Prospective Multicenter Evaluation

Group A Streptococcus is one of the leading causes of otorrhea. The performance of rapid antigen tests in 256 children with otorrhea showed excellent sensitivity, 97.3% (95% confidence interval: 90.7%-99.7%), and specificity, 100% (95% confidence interval: 98.0%-100%). In a period of increasing invasive and noninvasive group A Streptococcus infections, an early diagnosis could be useful.

Group A Streptococcus Pneumonia in a Previously Healthy Individual: Is It Still a Thing?

Group A streptococcus (GAS) is known to cause many different kinds of infections, including invasive pneumonia in rare cases. When it is the causative agent, it is associated with a more severe disease course, but it can often be adequately treated if caught early enough. We hereby present the case of a 32-year-old male with no past medical history who presented with fever, hemoptysis, and tachycardia. Laboratory results showed leukocytosis, hyponatremia, mild transaminitis, and elevated creatine kinase. Initial imaging findings and clinical presentation were concerning for tuberculosis (TB) vs. community-acquired pneumonia (CAP), as it yielded a consolidation in the right upper lobe. The patient had no obvious risk factor except for imprisonment two years prior to symptoms onset. Empirical antibiotics and steroids were started. Quantiferon and acid-fast bacteria (AFB) were negative, but sputum and blood cultures were positive for Streptococcus pyogenes, ruling out TB. Antibiotic therapy was narrowed down. The patient responded well to therapy, with subsequent resolution of symptoms. The current body of knowledge regarding respiratory infections caused by GAS is limited by multiple factors, including its relative rarity and the diversity of how it can present, especially in a developed country. Its mimicry characteristics of other clinical entities, such as TB, can be deceiving, which can delay appropriate treatment if it occurs in settings where the diagnostic tools are not readily available. By sharing more cases and atypical presentations of this disease, the clinical presentations of this pathogen can be more fully understood, and it can be more rapidly identified and treated.

Streptococcus pyogenes Infection-Induced Primary Peritonitis in a Healthy Adult Female: A Very Rare Causative Agent

A 44-year-old woman with an unremarkable medical history presented to another hospital complaining of lower abdominal pain and nausea. The clinical presentation was consistent with an acute abdomen, raising suspicion of gastrointestinal tract perforation. However, imaging studies failed to provide evidence of perforation. Subsequently, the patient was diagnosed with peritonitis of unknown origin and promptly administered broad-spectrum antibiotics in a fasting state. Although the patient initially exhibited unstable symptoms, hemodynamics, and serology, she gradually improved over three days, with values approaching normal levels. On the sixth day of hospitalization, a follow-up abdominal computed tomography scan revealed pleural effusions, extensive ascites, and intra-abdominal stranding. The thickened wall of the small intestine and intra-abdominal stranding that were suggestive of peritonitis were further exacerbated. On the seventh day of hospitalization, aerobic and anaerobic blood cultures revealed the presence of Gram-positive cocci, later confirmed to be Streptococcus pyogenes, leading to the diagnosis of S. pyogenes infection-induced primary peritonitis. The source of infection was identified as a 10 mm hydrosalpinx in the left fallopian tube, suggesting the possibility of retrograde infection. The patient ultimately made a complete recovery without relapse and has been doing well since. This case report highlights a unique and rare occurrence of primary peritonitis caused by group A Streptococcus associated with infection from a hydrosalpinx in an otherwise healthy and young female patient. The diagnosis of primary spontaneous bacterial peritonitis in such an individual presents an uncommon clinical manifestation, emphasizing the importance of considering atypical sources of peritoneal infection in clinical practice.

Atypical Case Presentation of Toxic Shock Syndrome

Toxic shock syndrome is a rare and life-threatening condition that is typically caused by group A Streptococcus or Staphylococcus aureus. It classically presents with fever, hypotension, sunburn-like rash, and multi-organ system failure. We describe a case of a 70-year-old male with this condition who had an atypical presentation of left chest wall pain and left shoulder pain after two mechanical falls along with hemodynamic stability. The patient rapidly deteriorated on his second hospital floor day, resulting in a higher complexity of care and management in the intensive care unit (ICU). Despite a number of resuscitative measures, therapies, and multidisciplinary care, the patient unfortunately passed away within 24 hours of his ICU care.

Non-contrast Enhancing Group A Streptococcus Subdural Empyema: An Illustrative Case Report of a Potential Radiographic Pitfall

Subdural empyemas (SDEs) are an uncommon complication of intracranial infection, typically presenting as a hypodense collection with peripheral contrast enhancement. Herein, we report two rare cases of SDE without contrast enhancement, both secondary to group A streptococcus. The first is a 27-year-old previously healthy female, at 27 weeks of gestational age who presented with fever, headache, neurological decline, and blood cultures positive for gram-positive cocci. The second case is a previously healthy 48-year-old male who presented with left-sided otalgia, fever, headache, and precipitous decline in altered mental status and hemiplegia. Computed tomography (CT) and magnetic resonance imaging (MRI) in both cases showed a subdural collection without contrast enhancement and without diffusion restriction. Despite appearances similar to subdural effusion, because of a heightened suspicion due to clinical decline, both were taken to surgery for irrigation and debridement which confirmed SDE. Both patients were treated with six weeks of intravenous antibiotics and eventually recovered without neurological deficits. SDEs are uncommon but clinically significant phenomena. These two cases demonstrate that SDEs in rare circumstances may present as non-enhancing subdural collections. Missing the diagnosis of SDE can have significant consequences to patient morbidity and mortality and as such, it not be excluded based on radiographic findings alone.

Group A Streptococcus Necrotizing Lymphadenitis: A Case Report

Necrotizing lymphadenitis (NL) is a rare entity that can occur as a complication of bacterial cervical lymphadenitis (CL) and is characterized by unilateral or bilateral cervical lymphadenopathy. NL most commonly presents in females and most reports have been in Japan. In this case, we present a 37-year-old male with no significant past medical history who presented with an unusual presentation and clinical course of NL. Initial workup for Epstein-Barr Virus (EBV) and other infectious etiology was negative. Yet, aspiration later revealed Group A Streptococcus. When the patient's pain and swelling did not subside with the initial antibiotic and supportive treatment, the patient underwent a repeat aspiration and biopsy that revealed a necrotic mass or lymph node. NL is uncommon and rarely due to infectious etiology. However, this marks a case in which a Group A Streptococcus was shown to be associated with subsequent necrotic lymph nodes and should allow practitioners to further consider an infectious etiology in the differential diagnosis of NL.

Group A Streptococcus Infections: Their Mechanisms, Epidemiology, and Current Scope of Vaccines

Group A streptococci (GAS) are gram-positive, cocci-shaped bacteria that cause a wide variety of infections and are a cause of significant health burden, particularly in lower- and middle-income nations. The GAS genome contains a number of virulence factors such as the M-protein, hyaluronic acid, C5a peptidase, etc. Despite its significant health burden across the globe, a proper vaccine against GAS infections is not yet available. Various candidates for an effective GAS vaccine are currently being researched. These are based on various parts of the streptococcal genome. These include candidates based on the N-terminal region of the M protein, the conserved C-terminal region of the M protein, and other parts of the streptococcal genome. The development of a vaccine against GAS infections is hampered by certain challenges, such as extensive genetic heterogeneity and high protein sequence variation. This review paper sheds light on the various virulence factors of GAS, their epidemiology, the different vaccine candidates currently being researched, and the challenges associated with M-protein and non-M-protein-based vaccines. This review also sheds light on the current scenario regarding the status of vaccine development against GAS-related infections.

Acute rheumatic fever in adult patients

Acute rheumatic fever (ARF) is considered as a disorder of children, and attacks in adults are usually a recurrence of disease acquired in the child's life. Although the incidence of ARF in children has a decreasing trend in developed countries, resurgent and sporadic epidemics still occur in adults. The first attacks of ARF in adult patients without a childhood history can lead to a diagnostic dilemma. A medical record review in adults at least 18 years of age with an arthralgia complaint fulfilling 2015 revised Jones criteria was performed from January 1, 2000 to December 31, 2019. Eleven ARF patients were identified, including 8 with initial attacks (6 females aged 26-42 years, 33.9 ± 5.3) and 3 pre-existing valvular heart disease with recurrent attacks (2 females aged 38-52 years, 45.0 ± 7.0). In addition to febrile pharyngitis and migratory polyarthritis in initial attacks, pericarditis was encountered in 1, valvulitis in 2, prolong PR interval in 3 and skin involvement in 2 patients with erythema marginatum and IgA vasculitis. All responded to antibiotics and nonsteroidal anti-inflammatory drugs therapy with normalized clinical and laboratory abnormalities, no new-onset carditis, and no recurrent disease during a long-term follow-up (3.8-19.8 years, 12.7 ± 5.4). A sporadic occurrence of adult ARF is observed in southern Taiwan. This disease should be considered by physicians for the differential diagnosis of febrile pharyngitis with arthritis and/or carditis in adults, even in areas with a low incidence of ARF.

Descending Mediastinitis in a Child: Diagnostic Challenges and a Different Treatment Approach

In children, spontaneous mediastinitis is a rare, severe and commonly misdiagnosed disease. Although standard of care treatment frequently involves surgery, we report a case of mediastinitis in a five-year-old child, successfully treated with 4 weeks of intravenous antibiotics. Ultrasound imaging was used to monitor patient response to conservative treatment while reducing radiation exposure.

A Case of Co-occurrence of COVID-19 and Group A Streptococcal Pharyngitis

Coronavirus disease 2019 (COVID-19) has swept the world with over hundred million of cases and millions of deaths. Upper respiratory tract symptoms including acute pharyngitis are the common symptoms of COVID-19, with a reported incidence of about 5%-17.4%. Group A Streptococcus (GAS) pharyngitis is a common cause of bacterial pharyngitis, with highest incidence between age 5 and 15, and it can still occur in adults with peak incidence at age 40. Herein, we report a case of co-occurrence of GAS and COVID-19 in a middle-aged man who presented with fever, sore throat, cough, and runny nose. To the best of our knowledge, we are the first to report this unique co-occurrence. Our case report aimed to raise the awareness among physician particularly in ambulatory and emergency department of not to have a singular focus on COVID-19 and forget to screen patient with acute pharyngitis for GAS.

Acute Rheumatic Fever: A Review of Essential Cutaneous and Histological Findings

Acute rheumatic fever (ARF) is an autoimmune response that may occur after infection with group A Streptococcus. Clinical manifestations are protean, making the syndrome difficult to recognize in the 21st century. Secondary prophylaxis with benzathine penicillin is given for 10 years after an episode of ARF to prevent recurrence and reduce the risk of rheumatic heart disease. This case highlights the importance of providing a detailed clinical history to the dermatopathologist when considering ARF in the differential diagnosis.

Prevalence, Clinical Features and Antibiotic Susceptibility of Group A Streptococcal Skin Infections in School Children in Urban Western and Northern Uganda

BACKGROUND

Group A Streptococcus (GAS) skin infections can lead to invasive sepsis, poststreptococcal glomerulonephritis, and potentially rheumatic heart disease (RHD). Within a study to identify predisposing factors of RHD in Ugandan schoolchildren, we determined the prevalence of skin infections and assessed the clinical features and antibiotic susceptibility of GAS skin infection.

METHODS

Cross-sectional study conducted at 3 urban primary schools in Western and Northern Uganda in March 2017. A dermatologist rendered clinical diagnoses and obtained a skin swab specimen from lesions with signs of bacterial infection. Beta-hemolytic colonies underwent Lancefield grouping, species identification by polymerase chain reaction and antimicrobial susceptibility testing.

RESULTS

From 3265 schoolchildren, we observed 32% with ≥1 fungal, 1.8% with ≥1 bacterial, 0.9% with ≥1 viral, and 0.2% with ≥1 ectoparasitic infection. Of 79, 25 (32%) specimens were GAS-positive, of which one-third demonstrated tetracycline resistance. Of 17 impetigo cases, 13 (76%) were located on the leg/foot and 3 (18%) on the head/neck. Prevalence of GAS skin infection was 0.8% (25 of 3265). In Northern Uganda, where subclinical definite RHD prevalence is 1.1%, GAS skin infection prevalence was 1.2% (4 of 343) and 0.9% (3 of 352).

CONCLUSION

This study identifies tetracycline-resistant GAS in Ugandan communities, suggests modified skin examination of exposed anatomic locations may be appropriate for population-based GAS skin infection studies, and underscores need for clear case definitions of GAS skin infection. Future studies are needed to evaluate the role of GAS skin infection in development of RHD in Ugandan communities.

Integrating the prevention and control of rheumatic heart disease into country health systems: a systematic review protocol

INTRODUCTION

Rheumatic heart disease (RHD) is a preventable chronic condition affecting the valves of the heart. RHD prevention and care programmes have historically originated in more developed countries, implemented in a targeted (or vertical) manner and evaluated using non-controlled approaches. Taking a broad view of the integration of RHD activities within the whole system is critical for health planning in low-income regions with a high burden of RHD and less robust health systems. Therefore, we propose to conduct a systematic review to assess RHD programme models in order to gain a better understanding of the extent of integration within relevant health systems.

METHODS AND ANALYSIS

A predefined search strategy will be used to search for relevant articles published in English from January 1990 to December 2017. Electronic databases PubMed, Scopus, Web of Science, Africa Wide, CINAHL, Cochrane Central Register of Controlled Trials, Google Scholar and Global Index Medicus will be searched, as well as reference lists of relevant articles published. A standardised data extraction form will be used to obtain information for analysis from the included studies. The quality, reliability and risk of bias of included studies will be assessed using design-specific criteria. Programme integration will be analysed according to stewardship and governance, financing, planning, service delivery, monitoring and evaluation, and demand generation. Programme inputs, outputs and impact will also be described.

ETHICS AND DISSEMINATION

No ethical approval is required. Findings will be disseminated in a peer-review journal in accordance with the Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines.

PROSPERO REGISTRATION NUMBER

CRD42017076307.

Exhaustion of the immune system by Group A Streptococcus necrotizing fasciitis: the occurrence of late secondary infections in a retrospective study

Background

Necrotizing fasciitis is a potentially lethal condition for which early and adequate treatment with surgical debridement and broad-spectrum intravenous antibiotics are essential for survival. It is hypothesized that Group A Streptococcus (GAS) necrotizing fasciitis causes exhaustion of the immune system, making these patients more susceptible for late secondary infections.

Methods

A retrospective study was conducted of all patients with necrotizing fasciitis between 2002 and 2016. Patients with necrotizing fasciitis based on macroscopic findings, positive Gram staining, culture or fresh frozen section of fascia biopsies were included. Patients with necrotizing fasciitis were divided into two groups based on the presence of GAS. Of both groups, clinical course, outcome and occurrence of late secondary infections were analyzed. For the occurrence of secondary infections, pneumonia was chosen as reference for late secondary infections.

Results

Eighty-one patients with necrotizing fasciitis were included of which 38 (47%) had GAS necrotizing fasciitis and 43 (53%) had non-GAS necrotizing fasciitis. Patients with GAS necrotizing fasciitis were younger (50 vs. 61 years, p=0.023) and more often classified as ASA I (45% vs. 14%, p=0.002) compared with patients with non-GAS necrotizing fasciitis. In-hospital mortality rate for necrotizing fasciitis was 32%. Patients with comorbidities were more likely to die of necrotizing fasciitis compared with patients without comorbidities (OR 7.41, 95% CI 1.58 to 34.63). Twelve patients (39%) with GAS necrotizing fasciitis developed pneumonia compared with four patients (13%) with non-GAS necrotizing fasciitis (p=0.017; OR 4.42, 95% CI 1.124 to 15.79). Median time from diagnosis to development of pneumonia in patients with GAS necrotizing fasciitis was 10 days (IQR 9).

Conclusion

Patients with GAS necrotizing fasciitis have an increased risk to develop late secondary infections during initial treatment for necrotizing fasciitis compared with patients with necrotizing fasciitis without involvement of GAS. This suggests exhaustion of the immune system after severe GAS infection.

Level of evidence

III.

Polyspecific Intravenous Immunoglobulin in Clindamycin-treated Patients With Streptococcal Toxic Shock Syndrome: A Systematic Review and Meta-analysis

We evaluated the effect of intravenous immunoglobulin (IVIG) on mortality in clindamycin-treated streptococcal toxic shock syndrome using a meta-analysis. In association with IVIG, mortality fell from 33.7% to 15.7% with remarkable consistency across the single randomized and four nonrandomized studies.

Postpartum Invasive Group A Streptococcus Infection: Case Report and Mini-review

The overall incidence of postpartum invasive group A streptococcal (GAS) disease is low in the United States. However, postpartum women are much more likely to develop GAS disease than nonpregnant women. Additionally, postpartum GAS has the potential to develop into a severe disease and a delay in diagnosis can have deadly consequences. This case describes a patient with invasive postpartum endometritis in the setting of diastases of the pubic symphysis. Sepsis secondary to the endometritis develops along with bilateral pneumonia. This case characterizes some of the typical and atypical symptoms a patient with invasive postpartum GAS can present with. Further, it outlines the timely identification of the disease and its appropriate treatment to prevent a potentially disastrous outcome.

Cardiac Myosin Epitopes Recognized by Autoantibody in Acute and Convalescent Rheumatic Fever

BACKGROUND

Acute rheumatic fever (ARF) is an autoimmune disorder associated with Streptococcus pyogenes infection. A prevailing hypothesis to account for this disease is that epitopes of self-antigens, such as cardiac myosin react to antibodies against S. pyogenes. The goal of our study was to confirm disease epitopes of cardiac myosin, identify immunodominant epitopes and to monitor the epitope response pattern in acute and convalescent rheumatic fever.

METHODS

Enzyme-linked immunosorbant assays were used to determine epitopes immunodominant in acute disease and to track the immune response longitudinally to document any changes in the epitope pattern in convalescent sera. Multiplex fluorescence immunoassay was used to correlate anti-streptolysin O (ASO) and anti-human cardiac myosin antibodies.

RESULTS

Disease-specific epitopes in rheumatic fever were identified as S2-1, 4 and 8. Epitopes S2-1, 4, 8 and 9 were found to be immunodominant in acute sera and S2-1, 8, 9, 29 and 30 in the convalescent sera. Frequency analysis showed that 50% of the ARF subjects responded to S2-8. S2-8 responders tended to maintain their epitope pattern throughout the convalescent period, whereas the S2-8 nonresponders tended to spread their responses to other epitopes later in the immune response. There was a significant correlation between anti-cardiac myosin and ASO titers. In addition, S2-8 responders showed elevated ASO titers compared with S2-8 non responders.

CONCLUSION

Our studies confirm the existence of S2-1, 4 and 8 as disease-specific epitopes. We provide evidence that cardiac myosin S2-8 responders remain epitope stable in convalescence, whereas S2-8 nonresponders shift to neoepitopes. Multiplex data indicated a correlation between elevated ASO and anti-human cardiac myosin antibody titers. Mapping of cardiac myosin epitopes recognized in rheumatic fever sera may identify immunophenotypes of rheumatic fever.

Streptococcal pharyngitis in schoolchildren in Bamako, Mali

BACKGROUND

Group A streptococcus (GAS) pharyngitis is associated with high rates of rheumatic heart disease in developing countries. We sought to identify guidelines for empiric treatment of pharyngitis in low-resource settings. To inform the design of GAS vaccines, we determined the emm types associated with pharyngitis among African schoolchildren.

METHODS

Surveillance for pharyngitis was conducted among children 5-16 years of age attending schools in Bamako, Mali. Students were encouraged to visit a study clinician when they had a sore throat. Enrollees underwent evaluation and throat swab for isolation of GAS. Strains were emm typed by standard methods.

RESULTS

GAS was isolated from 449 (25.5%) of the 1,759 sore throat episodes. Painful cervical adenopathy was identified in 403 children (89.8%) with GAS infection and was absent in 369 uninfected children (28.2%). Emm type was determined in 396 (88.2%) of the 449 culture-positive children; 70 types were represented and 14 types accounted for 49% of isolates. Based on the proportion of the 449 isolates bearing emm types included in the 30-valent vaccine (31.0%) plus nonvaccine types previously shown to react to vaccine-induced bactericidal antibodies (44.1%), the vaccine could protect against almost 75% of GAS infections among Bamako schoolchildren.

CONCLUSIONS

Two promising strategies could reduce rheumatic heart disease in low-resource settings. Administering antibiotics to children with sore throat and tender cervical adenopathy could treat most GAS-positive children while reducing use of unnecessary antibiotics for uninfected children. Broad coverage against M types associated with pharyngitis in Bamako schoolchildren might be achieved with the 30-valent GAS vaccine under development.

Group A streptococcal bacteremia without a source is associated with less severe disease in children

We analyzed characteristics of 86 Group A streptococcal bacteremia cases at Boston Children's Hospital from 1992 to 2012. Twenty-three percent of children had severe disease, using intensive care unit admission (18), disability (7) or death (2) as indicators. Children with bacteremia without a source (30% of cases) were less likely to have severe disease than children with focal infections in adjusted models.

Exploration of the host haemostatic system by group A streptococcus: implications in searching for novel antimicrobial therapies

The haemostatic system is heavily involved in the host response to infection. A number of host haemostatic factors, notably plasminogen and fibrinogen have been reported to bind and interact with various bacterial proteins. This review summarises the roles of host haemostatic factors such as plasminogen, factor V and fibrinogen in host defence against group A streptococcus infection and discusses the potential of targeting the host haemostatic system for therapeutic intervention against infectious diseases.

Ongoing purifying selection on intergenic spacers in group A streptococcus

Bacterial intergenic spacers are non-coding genomic regions enriched with cis-regulatory elements for gene expression. A population genetics approach was used to investigate the evolutionary force shaping the genetic diversity of intergenic spacers among 13 genomes of group A streptococcus (GAS). Analysis of 590 genes and their linked 5' intergenic spacers showed reduced nucleotide diversity in spacers compared to synonymous nucleotide diversity in protein-coding regions, suggestive of past purifying selection on spacers. Certain spacers showed elevated nucleotide diversity indicative of past homologous recombination with divergent genotypes. In addition, analysis of the difference between mean nucleotide difference and number of segregating sites showed evidence of an excess of rare variants both at nonsynonymous sites in genes and at sites in spacers, which is evidence that there are numerous slightly deleterious variants in GAS populations with potential effects on both protein sequences and gene expression.

Purulent pericarditis caused by group a streptococcus

Purulent pericarditis is a rare disease that is most often caused by organisms such as Staphylococcus aureus, Streptococcus pneumoniae, viridans streptococci, Haemophilus influenzae, and anaerobic bacteria. We present an unusual case of purulent pericarditis caused by Streptococcus pyogenes, Lancefield group A streptococcus (GAS), and we provide a review of the literature.

Characterization of a community cluster of group a streptococcal invasive disease in Maui, Hawaii

A community cluster of severe group A streptococcal skin infections occurred in Maui, Hawaii with 3 fatal cases of necrotizing fasciitis in 2002. emm types 1, 12, 58, 74, 85 and 109 were identified from 8 patients. emm types 74 and 109 have not been previously described in the United States according to the Centers for Disease Control and Prevention database. The identification of uncommon emm types suggested that group A streptococcal sero-types in Hawaii are different from those in the continental United States and can result in serious disease.