Fiebre reumática aguda en adultos corriendo el año 2023, diagnóstico poco frecuente. A propósito de un caso clínico

La fiebre reumática aguda es una enfermedad con baja incidencia en nuestra región. Sus complicaciones conllevan una elevada morbi-mortalidad. El diagnóstico es un desafío en la actualidad, teniendo la clínica un rol preponderante; permitiéndonos mantener una alta sospecha a pesar de su baja incidencia. Se presenta el caso clínico de un paciente sexo masculino cuyo diagnóstico fue un reto para el equipo de salud.

Acute rheumatic fever is a disease with low incidence in our region. Its complications involve high morbidity and mortality. Its diagnosis is currently a challenge, with clinical presentation playing a predominant role, allowing us to maintain a high diagnostic suspicion despite its low incidence. The clinical case of a male patient is presented, whose diagnosis posed a challenge for the healthcare team.

A Febre reumática aguda é uma doença com baixa incidência em nossa região. Suas complicações envolvem alta morbidade e mortalidade. Seu diagnóstico é atualmente um desafio, com a apresentação clínica desempenhando um papel predominante, permitindo-nos manter uma alta suspeita diagnóstica apesar de sua baixa incidência. É apresentado o caso clínico de um paciente do sexo masculino, cujo diagnóstico representou um desafio para a equipe de saúde.

Machine Learning in FTIR Spectrum for the Identification of Antibiotic Resistance: A Demonstration with Different Species of Microorganisms.

Recent studies introduced the importance of using machine learning algorithms in research focused on the identification of antibiotic resistance. In this study, we highlight the importance of building solid machine learning foundations to differentiate antimicrobial resistance among microorganisms. Using advanced machine learning algorithms, we established a methodology capable of analyzing the FTIR structural profile of the samples of Streptococcus pyogenes and Streptococcus mutans (Gram-positive), as well as Escherichia coli and Klebsiella pneumoniae (Gram-negative), demonstrating cross-sectional applicability in this focus on different microorganisms. The analysis focuses on specific biomolecules-Carbohydrates, Fatty Acids, and Proteins-in FTIR spectra, providing a multidimensional database that transcends microbial variability. The results highlight the ability of the method to consistently identify resistance patterns, regardless of the Gram classification of the bacteria and the species involved, reinforcing the premise that the structural characteristics identified are universal among the microorganisms tested. By validating this approach in four distinct species, our study proves the versatility and precision of the methodology used, in addition to bringing support to the development of an innovative protocol for the rapid and safe identification of antimicrobial resistance. This advance is crucial for optimizing treatment strategies and avoiding the spread of resistance. This emphasizes the relevance of specialized machine learning bases in effectively differentiating between resistance profiles in Gram-negative and Gram-positive bacteria to be implemented in the identification of antibiotic resistance. The obtained result has a high potential to be applied to clinical procedures.

Interkingdom biofilm of Streptococcus pyogenes and Candida albicans: establishment of an in vitro model and dose-response validation of antimicrobials.

Although Streptococcus pyogenes and Candida albicans may colonize tonsillar tissues, the interaction between them in mixed biofilms has been poorly explored. This study established an interkingdom biofilm model of S. pyogenes and C. albicans and verified the dose-response validation of antimicrobials. Biofilms were formed on microplates, in the presence or absence of a conditioning layer of human saliva, using Brain Heart Infusion (BHI) broth or artificial saliva (AS) as a culture medium, and with variations in the microorganism inoculation sequence. Biofilms grown in AS showed higher mass than those grown in BHI broth, and an opposite trend was observed for metabolism. The number of S. pyogenes colonies was lower in AS. Amoxicillin and nystatin showed dose-dependent effects. The inoculation of the two species at the same time, without prior exposure to saliva, and using BHI broth would be the model of choice for future studies assessing the effects of antimicrobials on dual S. pyogenes/C. albicans biofilms.

Group A streptococcus isolated in Guyana with reduced susceptibility to ß-lactam antibiotics.

Introduction. Streptococcus pyogenes [group A streptococci (GAS)] is the causative agent of pharyngitis and various other syndromes involving cellulitis, streptococcal toxic shock syndrome (STSS), and necrotising fasciitis. Although the prevalence of GAS infections globally remains high, necessitating the widespread use of ß-lactam antibiotics, GAS have remained largely susceptible to these agents. However, there have been several reports of GAS with reduced susceptibility harbouring mutations in genes for penicillin-binding proteins (PBPs). The objectives of this study were to examine the in vitro ß-lactam susceptibility patterns of group A streptococci, determine the prevalence of drug resistance, and ascertain whether such resistance could be attributed to mutations in specific PBP genes. Methods. In this study, we sought to use Sanger sequencing to identify mutations in PBP genes of Streptococcus pyogenes isolated from patients that required inpatient and outpatient care that could confer reduced PBP affinity for penicillin and/or cephalosporin antibiotics. All isolates were screened for susceptibility to penicillin, amoxicillin, and cefazolin using E-test strips. Results. While there were no documented cases of reduced susceptibility to penicillin or amoxicillin, 13 isolates had reduced susceptibility to cefazolin. Examination of pbp1a by Sanger sequencing revealed several isolates with single amino acid substitutions, which could potentially reduce the affinity of PBP 1A for cefazolin and possibly other first-generation cephalosporins. Conclusion. Penicillin and penicillin-derived antibiotics remain effective treatment options for GAS infections, but active surveillance is needed to monitor for changes to susceptibility patterns against these and other antibiotics and understand the genetic mechanisms contributing to them.

Correlation between the results of cultures and the molecular BIOFIRE® joint infection panel in a cohort of pediatric patients with bone and joint infections in Bogotá, Colombia.

Introduction: Bone and Joint Infections (BJI) have high morbidity. Methicillin resistant Staphylococcus aureus (MRSA) has increased. Culture-based diagnosis has difficult to recovering fastidious bacteria and detecting polymicrobial infections, molecular methods offer a promising improvement for the diagnosis of BJI with reduced time to result. The aim of the study was to determine the correlation between culture results and the Biofire joint infection panel (BJIP) in a cohort of pediatric patients with BJI. Materials and methods: Descriptive study. Patients admitted with probable o confirmed BJI between July 1, 2019 and February 28, 2021 at HOMI. Blood cultures, synovial and bone fluid samples were taken. Samples were kept at -70 °C. On September 2022, the panel was performed. Results: 32 patients were included. The average age was 83m (RIQ: 32-145). 23 (71.8%) patients had a positive culture. The most frequent microorganism were S. aureus 19 (83%), 11/19 (57.9%) Staphylococci isolates were MRSA. 24/32 (75%) were positive by panel, 20 positive detections were concordant with culture, there were 6 additional isolates by panel (2 S. aureus, 2 S. pyogenes, 1 K. kingae and 1 C. albicans), three microorganisms were isolated in culture but not in the panel. (2 S. aureus and 1 S. agalactiae). Two patients with coinfection were detected. All MRSA were detected by culture and panel. In 26 (81.3%) patients the etiology was documented by any method. Conclusion: These results showed a moderate level of agreement between BJIP and culture (κ = 0.47). The panel allowed the detection of fastidious bacteria including K. kingae and polymicrobial samples. There was a very good level of agreement between the panel and culture for the MRSA detection (κ = 1).

Efficacy of Alum-Adjuvanted Peptide and Carbohydrate Conjugate Vaccine Candidates against Group A Streptococcus Pharyngeal Infection in a Non-Human Primate Model.

Vaccine development against group A Streptococcus (GAS) has gained traction in the last decade, fuelled by recognition of the significant worldwide burden of the disease. Several vaccine candidates are currently being evaluated in preclinical and early clinical studies. Here, we investigate two conjugate vaccine candidates that have shown promise in mouse models of infection. Two antigens, the J8 peptide from the conserved C-terminal end of the M protein, and the group A carbohydrate lacking N-acetylglucosamine side chain (ΔGAC) were each conjugated to arginine deiminase (ADI), an anchorless surface protein from GAS. Both conjugate vaccine candidates combined with alum adjuvant were tested in a non-human primate (NHP) model of pharyngeal infection. High antibody titres were detected against J8 and ADI antigens, while high background antibody titres in NHP sera hindered accurate quantification of ΔGAC-specific antibodies. The severity of pharyngitis and tonsillitis signs, as well as the level of GAS colonisation, showed no significant differences in NHPs immunised with either conjugate vaccine candidate compared to NHPs in the negative control group.

Streptococcus pyogenes Lineage ST62/emm87: The International Spread of This Potentially Invasive Lineage.

Streptococcus pyogenes is known to be associated with a variety of infections, from pharyngitis to necrotizing fasciitis (flesh-eating disease). S. pyogenes of the ST62/emm87 lineage is recognized as one of the most frequently isolated lineages of invasive infections caused by this bacterium, which may be involved in hospital outbreaks and cluster infections. Despite this, comparative genomic and phylogenomic studies have not yet been carried out for this lineage. Thus, its virulence and antimicrobial susceptibility profiles are mostly unknown, as are the genetic relationships and evolutionary traits involving this lineage. Previously, a strain of S. pyogenes ST62/emm87 (37-97) was characterized in our lab for its ability to generate antibiotic-persistent cells, and therapeutic failure in severe invasive infections caused by this bacterial species is well-reported in the scientific literature. In this work, we analyzed genomic and phylogenomic characteristics and evaluated the virulence and resistance profiles of ST62/emm87 S. pyogenes from Brazil and international sources. Here we show that strains that form this lineage (ST62/emm87) are internationally spread, involved in invasive outbreaks, and share important virulence profiles with the most common emm types of S. pyogenes, such as emm1, emm3, emm12, and emm69, which are associated with most invasive infections caused by this bacterial species in the USA and Europe. Accordingly, the continued increase of ST62/emm87 in severe S. pyogenes diseases should not be underestimated.

Epidemiología de la faringitis estreptocócica. Período enero de 2018 - diciembre de 2021 / Epidemiology of streptococcal pharyngitis. January 2018 - December 21

La faringoamigdalitis es uno de los motivos más frecuentes de consulta en pediatría. Aproximadamente un 70-80% de las faringoamigdalitis son de etiología viral. El 20-30% restante son de origen bacteriano. El agente causal más frecuente es Streptococcus pyogenes (estreptococo ß-hemolítico del grupo A). El rol de Streptococcus dysgalactiae subsp. equisimilis, (estreptococos ß-hemolíticos grupos C y G) fue claramente establecido como agente etiológico en la faringitis bacteriana, tanto en niños como en adultos. Se realizó un análisis descriptivo y retrospectivo entre enero 2018 y diciembre de 2021. Se evaluó la prevalencia de faringitis estreptocócica, la edad, el período estacional, los agentes etiológicos y la resistencia a macrólidos durante los períodos pre-COVID-19 (2018-2019) y COVID-19 (2020-2021). Se analizaron 11 396 muestras de exudados de fauces de pacientes con sospecha de faringitis bacteriana; las mismas se procesaron mediante el uso de técnicas microbiológicas convencionales. En el período estudiado el porcentaje de positividad de los cultivos de exudados de fauces se mantuvo constante. Al comparar los períodos pre-COVID-19 (2018-2019) y COVID-19 (2020-2021) se observó una disminución en el número de aislados de S. pyogenes con un aumento de S. dysgalactiae subsp. equisimilis, mientras que la resistencia a macrólidos encontrada fue superior en S. pyogenes y para S. dysgalactiae subsp. equisimilis se mantuvo constante. Es importante realizar el cultivo para la identificación del agente etiológico y determinar la sensibilidad antibióticapara continuar con la vigilancia epidemiológica de la resistencia a los macrólidos, porque representan una opción en pacientes alérgicos a ß-lactámicos (AU)

Pharyngotonsillitis is one of the most frequent reasons for consultation in children. Approximately 70-80% of pharyngotonsillitis are of viral etiology. The remaining 20-30% are bacterial in origin. The most frequent causative agent is Streptococcus pyogenes (group A ß-hemolytic streptococcus). Streptococcus dysgalactiae subsp. equisimilis (ß-hemolytic streptococcus groups C and G) was clearly established as an etiologic agent in bacterial pharyngitis in both children and adults. A descriptive and retrospective analysis was conducted between January 2018 and December 2021. The prevalence of streptococcal pharyngitis, age, seasonal period, etiologic agents, and macrolide resistance during the pre-COVID-19 (2018-2019) and COVID-19 (2020-2021) periods were evaluated. We analyzed 11 396 specimens of swabs from patients with suspected bacterial pharyngitis. Conventional microbiological techniques were used. In the study period, the percentage of positivity of swab cultures remained constant. When comparing the preCOVID-19 (2018-2019) and COVID-19 (2020-2021) periods, a decrease in the number of S. pyogenes isolates was observed with an increase in S. dysgalactiae subsp. equisimilis, while the resistance to macrolides found was higher for S. pyogenes and remained constant for S. dysgalactiae subsp. equisimilis. The identification of the etiologic agent and determination of antibiotic sensitivity are important for epidemiological surveillance of macrolide resistance, as they are a treatment option in patients who are allergic to ß-lactams (AU)

Antimicrobial and wound healing potential of naphthoquinones encapsulated in nanochitosan.

Introduction: The use of chitosan in pharmaceutical formulations is an advantageous approach due to this compound intrinsic biodegradability and biocompatibility, as well as ready availability and low polymer cost. Methods: Herein, the naphthoquinones 3- chloromethylene-menadione (NQ1) and 2,3-dichloro-1,4-naphthoquinone (NQ2) were nanoencapsulated into chitosan (CNP) by the ionotropic gelatinization technique and characterized by DLS, FTIR, SEM, TGA and DSC, and their release profiles evaluated. The antimicrobial and wound healing activities were investigated. Results and Discussion: Homogeneous chitosan nanocapsulses of about 193 nm and Z potential ranging from +30.6 to +33.1 mV loaded with NQ1 (CNP-NQ1) or NQ2 (CNPQNQ2). With nanoencapsulation efficiencies of ≥ 96%, the solubility of naphthoquinones in aqueous environments was improved, making them suitable for biological system applications. The encapsulated naphthoquinones displayed a controlled release of approximately 80% for CNP-NQ1 and 90% for CNP-NQ2 over an 8 h period at 36°C. Both CNP-NQ1 and CNP-NQ2 retained the already established free naphthoquinone antimicrobial activity against two Staphylococcus aureus strains, Staphylococcus epidermidis, Streptococcus pyogenes and Pseudomonas aeruginosa. Although presenting low toxicity to healthy human cells, only CNP-NQ1 displayed therapeutic indices above 100 for S. aureus and S. epidermidis and above 27 for S. pyogenes and P. aeruginosa, allowing for safe use in human tissues. Furthermore, CNP-NQ1 did not impair the migration of human fibroblast cells in scratch assays, adding promising wound healing properties to this formulation. These findings emphasize that CNP-NQ1 may be useful in protecting injured skin tissue from bacterial contamination, avoiding skin infections not only by reducing bacterial loads but also by accelerating the healing process until complete dermal tissue recovery.

Detección rápida de antígenos de Streptococcus pyogenes en pacientes de 0 a 14 años asistidos en dos servicios de urgencia pediátrica (14/2/2018-13/4/2018) / Rapid detection of Streptococcus pyogenes' antigens in patients of 0 to 14 years of age, assisted in two pediatric emergency wards (2/14/2018-4/13/2018) / Detecção rápida de antígenos de Streptococcus pyogenes em pacientes de 0 a 14 anos de idade assistidos por emergência pediátrica (14/2/2018-13/4/2018)

Introducción: las infecciones estreptocócicas pueden presentarse con fiebre, inflamación faringoamigdalina con o sin exudados, petequias en el paladar, adenitis cervical, exantema escarlatiniforme y / o dolor abdominal. Resulta útil en área de urgencia disponer de pruebas de detección rápida de antígenos de S. pyogenes (DRASP) de alta especificidad y sensibilidad algo menor. Objetivos: conocer la utilidad de un test de DRASP en 2 servicios de Urgencia Pediátrica, describiendo las características clínicas y epidemiológicas de los pacientes estudiados durante el período de la investigación y su correlación con el cultivo de exudado faríngeo mediante el cálculo de sensibilidad (S), especificidad (E), valor predictivo positivo (VPP) y valor predictivo negativo (VPN). Material y métodos: estudio prospectivo, observacional, transversal en dos servicios de emergencia pediátrica. Se incluyeron niños a los que se les realizó DRASP y exudado faríngeo (EF) entre el 14 de febrero y el 13 de abril de 2018. Se registró: sexo, edad, motivo de consulta, diagnóstico, tratamiento, destino, resultado del test y de cultivo faríngeo. Se calcularon S, E, VPP y VPN. Resultados: n=241 niños. Rango 8 meses - 14 años, media 6 años. Consultaron por fiebre 103 niños (42,7%); por odinofagia 48, por erupción 11 y 47 por otros síntomas. Al 95% de los niños se le otorgó el alta. DRASP negativos 87,6% (N: 211) y positivos 12,9% (N: 31). EF negativos 80,1% (n: 193) y positivos para SßHGA en 13,7% (n: 33). La sensibilidad de la prueba fue del 52% y su especificidad del 93%. El VPP 55% y el negativo 92%. El diagnóstico más frecuente fue faringitis viral 132 (54,7%). Conclusiones: el test se aplicó fundamentalmente a escolares febriles, algunos con odinofagia. Contribuye a diferenciar en forma rápida la etiología y habilita a no usar antibióticos en caso de resultado negativo. Estos resultados avalan el uso de DRASP en la urgencia pediátrica.

Introduction: streptococcal infections can show fever, pharyngotonsillar inflammation with or without swabs, palatal petechiae, cervical adenitis, scarlatiniform rash and/or abdominal pain. Rapid detection tests for S. pyogenes antigens (DRASP) with high specificity and somewhat lower sensitivity are a useful at the Emergency Ward. Objectives: know the usefulness of a DRASP test in 2 Pediatric Emergency, describe the clinical and epidemiological characteristics of the patients studied during the research period and its correlation with the culture of pharyngeal exudates by calculating sensitivity (S) , specificity (S), positive predictive value (PPV), and negative predictive value (NPV). Material and Methods: prospective, observational, cross-sectional study carried out in two pediatric emergency wards. We included children who underwent DRASP and pharyngeal swab (PS) between February 14 and April 13, 2018. The following data were recorded: sex, age, reason for consultation, diagnosis, treatment, destination, test results and throat cultures. S, S, PPV and NPV were calculated. Results: n=241 children. Range 8 months - 14 years, average 6 years. 103 children (42.7%) consulted due to fever; 48 due to sore throat, 11 due to rash and 47 due to other symptoms. 95% of children were discharged. DRASP negative 87.6% (N: 211) and positive 12.9% (N: 31). Negative EP 80.1% (n: 193) and positive for SßHGA in 13.7% (n: 33). The test sensitivity was 52% and specificity 93%. The PPV 55% and the negative 92%. The most frequent diagnosis was viral pharyngitis 132 (54.7%). Conclusions: the test was applied mainly to febrile schoolchildren, some with odynophagia. A quick etiology differentiation is helpful, since it prevents antibiotics from being used in the event of a negative result. These results support the use of DRASP in pediatric emergency wards.

Introdução: as infecções estreptocócicas manifestam-se com febre, inflamação faringotonsilar com ou sem exsudado, petéquias palatinas, adenite cervical, erupção cutânea escarlatiniforme e/ou dor abdominal. Nos serviços de emergência é útil realizar testes de detecção rápida para antígenos de S. pyogenes (DRASP) com alta especificidade e sensibilidade um pouco mais baixa Objetivos: conhecer a utilidade do teste DRASP em 2 Emergências Pediátricas, descrever as características clínicas e epidemiológicas dos pacientes estudados durante o período da pesquisa e sua correlação com a cultura de exsudatos faríngeos por meio do cálculo de sensibilidade (S) , especificidade (S), positivo valor preditivo (VPP) e valor preditivo negativo (VPN). Material e métodos: estudo prospectivo, observacional, transversal, realizado em duas unidades de emergência pediátrica. Foram incluídas crianças que realizaram DRASP e swab faríngeo (PS) entre 14 de fevereiro e 13 de abril de 2018. Foram registrados os seguintes dados: sexo, idade, motivo da consulta, diagnóstico, tratamento, destino, resultados de exames e culturas de garganta. S, S, VPP e VPN foram calculados. Resultados: n=241 crianças. Faixa 8 meses - 14 anos, média 6 anos. 103 crianças (42,7%) consultadas por febre; 48 por dor de garganta, 11 por erupção cutânea e 47 por outros sintomas. 95% das crianças receberam alta. DRASP negativo 87,6% (N: 211) e positivo 12,9% (N: 31). EP negativo 80,1% (n: 193) e positivo para SßHGA em 13,7% (n: 33). A sensibilidade do teste foi de 52% e a especificidade de 93%. O PPV 55% e o negativo 92%. O diagnóstico mais frequente foi faringite viral 132 (54,7%). Conclusões: o teste foi aplicado principalmente em escolares febris, alguns com odinofagia. A rápida diferenciação etiológica é útil, pois evita o uso de antibióticos em caso de resultado negativo. Esses resultados apoiam o uso do DRASP em enfermarias de emergência pediátrica.

Enfermedades invasoras por Streptococcus pyogenes en población pediátrica. Caracterización clínico-molecular 2014-2020 / Invasive diseases due to Streptococcus pyogenes in the pediatric population. Clinical-molecular characterization 2014-2020

INTRODUCCIÓN: Streptococcuspyogenes (EGA) es agente de enfermedad invasora (EI); su alta morbimortalidad exige vigilancia epidemiológica. OBJETIVO: Describir características clínicas y epidemiológicas de niños hospitalizados con EI por EGA en un centro de referencia de Uruguay del 1/1/2014 al 31/12/2020 incluyendo el estudio de los factores de virulencia encontrados en las cepas aisladas. MATERIALES Y MÉTODOS: Descriptivo y retrospectivo. Definición de caso: aislamiento de EGA. en sitios estériles. Variables: epidemiológicas, clínicas, laboratorio, tratamiento y evolución. Se tipificó por secuenciación del gen emm. Se obtuvieron perfiles cromosómicos por digestión del ADN con la enzima SmaI. Presencia de los genes que codifican SpeB, SpeA, SpeC y Ssa, y susceptibilidad a antimicrobianos. RESULTADOS: Tasa de admisiones: 3,98/10.000. Se incluyeron 22 pacientes; infección osteoarticular (n = 11), infección pleuropulmonar (n = 6), absceso no cutáneo (n = 4) y aislamiento en sangre (n = 1). Media de edad: 44 meses; 8 fueron graves, siendo su media de edad menor (16 meses) Todas los casos con neumonías fueron graves y un paciente falleció. Se secuenciaron 12 cepas: 5 emm1 (4 emm 1.29 y 1 emm 1) y 1 de cada uno de los siguientes: emm 6.4, emm 81, emm12, emm28, emm 22, emm 87, emm 11. Todas eran SpeB+. Perfiles de toxinas: SpeA+SpeC-Ssa-(5), SpeA-SpeC+Ssa-(4) SpeA-SpeC-Ssa-(2) y SpeA-SpeC+Ssa+ (2). CONCLUSIONES: Este estudio permite dar continuidad a un estudio previo. Se logró mayor tipificación de EGA. que puede contribuir a su conocimiento clínico molecular. No hubo registro de pacientes con diagnóstico de SST ni de fascitis necrosante, a diferencia de la serie anterior.

BACKGROUND: Streptococcus pyogenes (GAS) is an agent of invasive disease (ID); its high morbidity and mortality requires epidemiological surveillance. AIM: To describe the clinical and epidemiological characteristics of children hospitalized with ID due to GAS in a reference center in Uruguay from January 1-2014 to December 31-2020, including a study of virulence factors. METHODS: Descriptive and retrospective. Case definition: Isolation of GAS in sterile sites. Variables: epidemiological, clinical, laboratory, treatment and evolution. Strains were typified by sequencing of the emm gene. Chromosomal profiles were obtained by digestion of the DNA. with the Smal enzyme. Presence of SpeB, SpeA and SpeC genes and susceptibility to antibiotics were performed. RESULTS: Admissions rate: 3.98/10,000. 22 patients were included; osteoarticular infection (n = 11), pleuropulmonary infection (n = 6), non-cutaneous abscess (n = 4) and blood isolation (n = 1). Mean age: 44 months; 8 cases were severe, their mean age was lower (16 months). All pneumonia cases were severe and one patient died. Twelve strains were sequenced: 5 emm1 (4 emm1.29 and 1 emm1) and 1 of each: emm6.4, emm81, emm 12, emm28, emm 22, emm 87, emm 11. All were SpeB+. Toxin profiles: SpeA+SpeC-Ssa-(5), SpeA-SpeC+Ssa-(4) SpeA-SpeC-Ssa-(2) and SpeA-SpeC+Ssa+(2). CONCLUSIONS: This study allows to give continuity to a previous study. Greater typing of GAS was achieved, which may contribute to its molecular clinical knowledge. There was no record of patients diagnosed with TSS or necrotizing fascitis, unlike the previous series.

Cellular Growth Arrest and Efflux Pumps Are Associated With Antibiotic Persisters in Streptococcus pyogenes Induced in Biofilm-Like Environments.

Streptococcus pyogenes (group A Streptococcus-GAS) is an important pathogen for humans. GAS has been associated with severe and invasive diseases. Despite the fact that these bacteria remain universally susceptible to penicillin, therapeutic failures have been reported in some GAS infections. Many hypotheses have been proposed to explain these antibiotic-unresponsive infections; however, none of them have fully elucidated this phenomenon. In this study, we show that GAS strains have the ability to form antimicrobial persisters when inoculated on abiotic surfaces to form a film of bacterial agglomerates (biofilm-like environment). Our data suggest that efflux pumps were possibly involved in this phenomenon. In fact, gene expression assays by real-time qRT-PCR showed upregulation of some genes associated with efflux pumps in persisters arising in the presence of penicillin. Phenotypic reversion assay and whole-genome sequencing indicated that this event was due to non-inherited resistance mechanisms. The persister cells showed downregulation of genes associated with protein biosynthesis and cell growth, as demonstrated by gene expression assays. Moreover, the proteomic analysis revealed that susceptible cells express higher levels of ribosome proteins. It is remarkable that previous studies have reported the recovery of S. pyogenes viable cells from tissue biopsies of patients presented with GAS invasive infections and submitted to therapy with antibiotics. The persistence phenomenon described herein brings new insights into the origin of therapeutic failures in S. pyogenes infections. Multifactorial mechanisms involving protein synthesis inhibition, cell growth impairment and efflux pumps seem to play roles in the formation of antimicrobial persisters in S. pyogenes.

Antimicrobial Resistance among Beta-Hemolytic Streptococcus in Brazil: An Overview.

Streptococcus pyogenes, Streptococcus agalactiae and Streptococcus dysgalactiae subsp. equisimilis (SDSE) are the beta-hemolytic streptococci species with the most clinical relevance to humans. These species are responsible for several infections, ranging from mild to life-threatening diseases. Although resistance to recommended drugs has not been so critical as detected in other species, it has occurred in diverse regions. In Brazil, it is possible to observe an increasing macrolide and lincosamide resistance trend due to the spread of polyclonal strains. Macrolide-lincosamide-streptogramin B (MLS) resistance phenotypes have been prevalent among S. agalactiae and S. pyogenes, while M phenotype (resistance only to macrolides) has prevailed among SDSE resistant isolates. Fluoroquinolone resistance is rare in this country, reported only in S.agalactiae and S.pyogenes. This is due to nucleotide substitutions in gyrA and parC genes. Reduced penicillin susceptibility and vancomycin resistance, detected in other regions, have not yet been reported in Brazil. Tetracycline is not a therapeutical option, and resistance has occurred at high levels, especially among S.agalactiae. These findings highlight the need for continuous monitoring in order to track the occurrence of antimicrobial resistance among beta-hemolytic streptococci species circulating in this country.

Necrotizing Streptococcus pyogenes Infiltrating Conjunctiva and Tenon's Capsule: A Case Report.

We report a case of a patient with necrotizing infection of the conjunctiva and Tenon's capsule caused by Streptococcus pyogenes, a rare and atypical ophthalmologic condition. A 50-years-old male patient with acute red-eye, purulent discharge, and pain diagnosed with post-septal cellulitis presented with a yellowish and dense membrane covering the ocular surface with necrotic Tenon's capsule. Patient was hospitalized, and intravenous antibiotics were initiated (ceftriaxone and clindamycin). Topical antibiotics and corticosteroids were also administered, and the infection was eradicated in 2 weeks. Ancillary exams excluded rheumatologic involvement. Conjunctival culture confirmed Streptococcus pyogenes growth. Tenon's biopsy revealed unspecific acute inflammatory necrosis. This is an uncommon condition in daily ophthalmological clinic. Literature review reported 3 cases associated with previous ocular surgery.

In vitro antimicrobial activity of Caesalpinia coriaria (Jacq. ) Willd extracts on Streptococcus pyogenes and Candida albicans / Actividad antimicrobiana in vitro de extractos de Caesalpinia coriaria (Jacq. ) Willd sobre Streptococcus pyogenes y Candida albicans

Background: "Dividivi" Caesalpinia coriaria (Jacq.) Willd fruits are traditionally used by the Wayuú community in La Guajira (Colombia) to treat oral and skin cavity diseases caused by bacteria and fungi. Streptococcus pyogenes is a gram-positive cocci of group A (beta-hemolytic) that is the cause of pharyngeal disease, scarlet fever, cellulitis, erysipelas, or toxic shock-like syndrome. Alternatively, Candida albicans is a yeast-like fungus that is a normal flora of the digestive tract, vagina, or skin folds; it has been known to be the root cause of opportunistic diseases such as diaper rash, oral and esophagus thrush, or vulvovaginitis. Objective: This study evaluated the antimicrobial activity of methanolic and ethanolic extracts of C. coriaria (Jacq.) Willddry fruits on S. pyogenes ATCC 12384andC. albicans ATTC 14053. Method: C. coriaria extracts were obtained from the Soxhlet method using two solvents (methanol and ethanol 98%) prepared from pulverized fruits. A phytochemical test and an antimicrobial activity assay were performed using the obtained extracts and tested using S. pyogenes ATCC 12384 and C. albicans ATTC 14053 strains. Results: A phytochemical profile was performed, examining the presence of bioactive metabolites (tannins, alkaloids, glycosides, saponins, and anthraquinones) from each extract. Antimicrobial susceptibility tests showed that the ethanolic extract inhibited S. pyogenes ATCC 12384,causing inhibition halos of 14.1 ± 0.1 mm and a Minimum Inhibitory Concentration (MIC) of 172 mg/ml, and C. albicans test shows inhibition halos of 16.1 ± 0.2 mm and MIC of 212 mg/ml. Additionally, the methanolic extract inhibited S. pyogenes with inhibition halos of 15.2 ± 0.2 mm and MIC of 152 mg/ml; no inhibitory effect was observed on C. albicans.Conclusion: This study revealed that C. coriaria has an antimicrobial effect on the tested species opening the field of its possible use as a therapeutic agent

Introducción: Los frutos del "Dividivi" Caesalpinia coriaria (Jacq.) Willd son usados tradicionalmente por la comunidad indígena Wayuú en La Guajira (Colombia) para el tratamiento de enfermedades de la cavidad bucal y cutáneas ocasionadas por bacterias y hongos. Streptococcuspyogenes es un coco grampositivo del grupo A (beta-hemolítico) que es la causa de enfermedad faríngea, escarlatina, celulitis, erisipela o síndrome tipo shock tóxico. Candida albicans es un hongo levaduriforme que es flora normal del tracto digestivo, la vagina o los pliegues de la piel; se sabe que es la causa principal de enfermedades oportunistas como la dermatitis del pañal, aftas bucales y esofágicas, o vulvovaginitis. Objetivo: El objetivo de este estudio fue evaluar la actividad antimicrobiana de extractos metanólicos y etanólicos de frutos secos sobre microorganismos patógenos específicamente S. pyogenes ATCC 12384yC. albicansATTC 14053. Método: A partir de frutos polverizados de C. coriaria, usando el método Soxlet, se evaluaron dos solventes (metanol y etanol al 98%), los cuales, fueron usados para estudiar su actividad antimicrobiana evaluando su efecto en cepas de S. pyogenes ATCC 12384 y C. albicans ATTC 14053. Resultados: Mediante un perfil fitoquímico se determinó la presencia de grupos de metabolitos secundarios con compuestos bioactivos (taninos, alcaloides, glucósidos, saponinas, y antraquinonas). Las pruebas de sensibilidad antimicrobiana mostraron que el extracto etanólico tuvo un efecto inhibidor sobre S. pyogenesATCC 12384 con halos de inhibición de 14.1 ± 0.1 mm y una concentración mínima inhibitoria (CMI) de 172 mg/mL, y sobre C. albicans se presentaron halos de inhibición de 16.1 ± 0.2 mm y CMI de 212 mg/mL, mientras que el extracto metanólico tuvo un efecto inhibidor sobre S. pyogenes con halos de inhibición de 15.2 ± 0.2 mm y CMI de 152 mg/mL no se observó efecto inhibidor sobre C. albicans. Conclusión: Este estudio demostró que C. coriaria tiene efecto antimicrobiano en las especies evaluadas, abriendo un campo de investigación en la evaluación de su uso como agente terapéutico

Ectopic Spacer Acquisition in Streptococcus thermophilus CRISPR3 Array.

Streptococcus thermophilus relies heavily on two type II-A CRISPR-Cas systems, CRISPR1 and CRISPR3, to resist siphophage infections. One hallmark of these systems is the integration of a new spacer at the 5' end of the CRISPR arrays following phage infection. However, we have previously shown that ectopic acquisition of spacers can occur within the CRISPR1 array. Here, we present evidence of the acquisition of new spacers within the array of CRISPR3 of S. thermophilus. The analysis of randomly selected bacteriophage-insensitive mutants of the strain Uy01 obtained after phage infection, as well as the comparison with other S. thermophilus strains with similar CRISPR3 content, showed that a specific spacer within the array could be responsible for misguiding the adaptation complex. These results also indicate that while the vast majority of new spacers are added at the 5' end of the CRISPR array, ectopic spacer acquisition is a common feature of both CRISPR1 and CRISPR3 systems in S. thermophilus, and it can still provide phage resistance. Ectopic spacer acquisition also appears to have occurred naturally in some strains of Streptococcus pyogenes, suggesting that it is a general phenomenon, at least in type II-A systems.

Sensibilidad disminuida a los antibóticos Beta-Lactamicos en estreptococos Beta-Hemolíticos / Decreased sensitivity to beta-lactam antibiotics in beta-hemolytic streptococci

Últimamente, se están detectando mutaciones en las proteínas ligadoras de penicilina (PBP) de los estreptococos beta-hemolíticos que corresponden a sitios que en Streptococcus pneumoniae han determinado sensibilidad disminuida a los antibióticos beta-lactámicos. Primero, se describieron cepas con sensibilidad intermedia a penicilina en Streptococcus agalactiae (estreptococos del grupo B), luego en Streptococcus dysgalactiae subsp. equisimilis (mayormente grupos C y G) y, más recientemente, cepas con sensibilidad disminuida a aminopenicilinas y cefalosporinas de tercera generación en Streptococcus pyogenes (grupo A). El costo biológico de estas modificaciones nos permite pensar que los niveles de resistencia no han de ser tan elevados como para comprometer por ahora la efectividad clínica de los beta-lactámicos (AU)

Recently, mutations in penicillin-binding proteins (PBPs) of beta-hemolytic streptococci have been detected corresponding to sites that in Streptococcus pneumoniae have been determined to have decreased sensitivity to beta-lactam antibiotics. First, strains with intermediate sensitivity to penicillin were described in Streptococcus agalactiae (group B streptococci), subsequently in Streptococcus dysgalactiae subsp. equisimilis (mainly groups C and G) and, more recently, strains with decreased sensitivity to third-generation aminopenicillins and cephalosporins were found in Streptococcus pyogenes (group A). The biological cost of these modifications suggests that, for now, resistance levels are not high enough to compromise the clinical effectiveness of beta-lactams (AU)

Poliartritis séptica y fascitis necrotizante en un paciente inmunocompetente. Reporte de caso / Septic polyarthritis and necrotizing fascitis in an immunocompetent patient. Case report

La presentación de poliartritis séptica en un paciente inmunocompetente es infrecuente, aún más lo es la presentación de la mencionada junto con fascitis necrotizante en el contexto de infección por Streptococcus Pyogenes (SP). Se presenta el caso de un paciente masculino de 54 años, recluido, sin antecedentes médicos relevantes, inmunocompetente, quien debuta con un cuadro clínico de poliartritis séptica en rodilla bilateral y tobillo izquierdo. Recibe manejo con múltiples lavados y desbridamientos quirúrgicos, desarrolla fascitis necrotizante de la cara posterior de la pierna izquierda, recibe a su vez manejo quirúrgico para dicha condición (incluyendo aplicación de terapia de vacío), al igual que antibioticoterapia enfocada al manejo del germen aislado (Penicilina + vancomicina). Sin embargo, tras un mes de manejo conjunto con servicios de Cirugía Plástica, Dermatología, Ortopedia, así como vigilancia en Unidad de Cuidados Intensivos, termina con un desenlace fatal tras presentar falla multiorgánica. La infección por el SP puede resultar en una elevada morbilidad para él paciente e incluso un desenlace mortal secundario a un compromiso sistémico de muy difícil manejo. El diagnóstico oportuno, así como un tratamiento médico y quirúrgico agresivo pueden no ser suficientes para el control de la infección, incluso en pacientes sin compromiso inmunológico previo. Asimismo, un enfoque multidisciplinario debe corresponder al estándar de manejo con el fin de controlar aquellas condiciones predisponentes de infección. Este es el primer caso reportado en la literatura nacional en relación con estas dos fatales condiciones. Finalmente se pretende resaltar que a pesar de que esta infección suele comprometer infantes y pacientes inmunocomprometidos, no se debe obviar su diagnóstico en pacientes previamente sanos, especialmente en casos de infecciones de rápida diseminación y poca respuesta al manejo adecuado.

Septic polyarthritis in an immunocompetent patient is highly rare, even more when it coexists with necrotizing fasciitis caused by Streptococcus Pyogenes (SP). A 54 year old, immunocompetent male patient is presented herein. The patient had no relevant previous illness, before the installation of a septic arthritis of both knees and he's left ankle. He receives treatment with sequential surgical debridement, then develops necrotizing fasciitis of the posterior aspect of the left leg requiring adequate treatment for such condition (including Vacuum Assisted Closure), as well as antibiotic therapy for the specific infecting microorganism (Penicillin + Vancomycin). Nonetheless, after a month of surgical management between Plastic Surgery, Dermatology, Orthopaedics as well as surveillance in the Intensive Care Unit, the patient dies after multi organic failure. Infection caused by SP might entail high morbidity for a patient and even end with death of the aforementioned caused by a hard to manage systemic organic failure. The adequate diagnosis, as well as aggressive medical and surgical management could not be enough for controlling the infection, even in patients without previous immunological compromise. At the same time, a multidisciplinary approach must be the standard of treatment, aiming to control predisposing infectious conditions. This is the first case reported in national literature related to these two fatal conditions. Finally, one of the purposes of this report is to highlight that despite reports of this microorganism infecting infants and immunocompromised patients, it must not be obviated in healthy patients, especially in cases of rapidly spreading infection and scarce response to adequate management.

Evaluation of a rapid diagnostic test for the detection of Streptococcus pyogenes in invasive infections / Evaluación de una prueba diagnóstica rápida para la detección de Streptococcus pyogenes en infecciones invasivas

Abstract Invasive Streptococcus pyogenes diseases represent the most severe form of infection produced by this microorganism. Early diagnosis and treatment are important, due to its potential severity. Etiological confirmation of invasive infection is performed by culture, which takes between 18 and 48 h. We tested a rapid immunochromatographic assay directly from clinical samples from normally sterile sites and positive blood culture bottles when pos-itive cocci chains were observed by Gram staining. Eighty samples were analyzed. The rapid test was positive in 35 samples: in 34 of them S. pyogenes was confirmed by culture. The immunochromatographic method showed 97.1% sensitivity and 97.8% specificity. The strept A® immunochromatographic rapid test allows to obtain reliable results in less than 10min and is accessible to any microbiology laboratory. This study demonstrates the potential use of a rapid immunochromatographic method directly from clinical samples and positive blood cultures.

Resumen La enfermedad invasiva por Streptococcus pyogenes representa la forma más grave de infección producida por este microorganismo y requiere un rápido diagnóstico, a fin de instaurar un tratamiento adecuado. La confirmación etiológica de esta infección se realiza por cultivo, lo que puede llevar entre 18 y 48 h. En este estudio ensayamos una prueba inmunocromatográfica rápida directamente de muestras clínicas de sitios normalmente estériles y de botellas de hemocultivos positivos cuando la coloración de Gram evidenció cocos gram positivos en cadena. Se analizaron 80 muestras. La prueba rápida fue positiva en 35 muestras: en 34 de ellas se confirmó la presencia de S. pyogenes por cultivo. La sensibilidad y la especificidad de la prueba fueron del 97,1 y el 97,8%, respectivamente. La prueba inmunocromatográfica rápida monteBIO Strep A® permite obtener resultados confiables en menos de 10 min y es accesible para cualquier laboratorio de microbiología. Este estudio demuestra la utilidad de dicha prueba para ser practicada directamente en muestras clínicas y botellas de hemocultivos positivos.

Meningitis por Streptococcus pyogenes: informe de un caso pediátrico / Streptococcus pyogenes meningitis: a pediatric case report

La meningitis por estreptococo beta hemolítico, en particular del grupo A, o Streptococcus pyogenes, es una rara localización del grupo de infecciones invasivas por este microorganismo. Se presenta con frecuencia en niños sanos, sin factores predisponentes. Representa el 0,2-1 % de todas las meningitis. Generalmente, se instala por diseminación de la infección de un foco cercano. El agregado de clindamicina mejora la eficacia del tratamiento por su acción de inhibición de la síntesis proteica, que incluye la producción de toxina. La clindamicina incrementa la acción bactericida al actuar sobre el ribosoma bacteriano. La patogenia de la enfermedad no es clara; se propuso la asociación con exotoxinas. La coinfección con el virus influenza favorecería infecciones invasivas. Se presenta el caso de un niño de 6 años de edad previamente sano con diagnóstico de meningitis por estreptococo beta hemolítico del grupo A, localización poco frecuente en niños.

Beta hemolytic particularly of group A Streptococcus meningitis, is a rare site of the group of invasive infections caused by this microorganism. It occurs frequently in healthy children, without predisposing factors. It represents 0.2-1 % of all meningitis. It is usually installed by dissemination from a nearby focus. The addition of clindamycin improves the treatment efficacy by inhibition of bacterial protein synthesis, including toxin production. The pathogenesis of the disease is not clear, the association with exotoxins was proposed. Co-infection with the influenza virus would favor invasive infections. We present this case of a previously healthy 6-year-old boy with a diagnosis of beta hemolytic Streptococcus meningitis group A, a rare location in children.