RESUMEN
The long-acting lipoglycopeptides (LGPs) dalbavancin and oritavancin are semisynthetic antimicrobials with broad and potent activity against Gram-positive bacterial pathogens. While they are approved by the Food and Drug Administration for acute bacterial skin and soft tissue infections, their pharmacological properties suggest a potential role of these agents for the treatment of deep-seated and severe infections, such as bloodstream and bone and joint infections. The use of these antimicrobials is particularly appealing when prolonged therapy, early discharge, and avoidance of long-term intravascular catheter access are desirable or when multidrug-resistant bacteria are suspected. This review describes the current evidence for the use of oritavancin and dalbavancin in the treatment of invasive infections, as well as the hurdles that are preventing their optimal use. Moreover, this review discusses the current knowledge gaps that need to be filled to understand the potential role of LGPs in highly needed clinical scenarios and the ongoing clinical studies that aim to address these voids in the upcoming years.
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Antiinfecciosos , Infecciones por Bacterias Grampositivas , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Antiinfecciosos/farmacología , Antiinfecciosos/uso terapéutico , Glicopéptidos/química , Glicopéptidos/farmacología , Glicopéptidos/uso terapéutico , Infecciones por Bacterias Grampositivas/tratamiento farmacológico , Humanos , Lipoglucopéptidos/uso terapéutico , Teicoplanina/farmacología , Teicoplanina/uso terapéuticoRESUMEN
Antistaphylococcal penicillins and cefazolin remain the primary treatments for infections with methicillin-susceptible Staphylococcus aureus (MSSA). The cefazolin inoculum effect (CzIE) causes the cefazolin MIC to be elevated in proportion to the number of bacteria in the inoculum. The objective of this multicenter study was to evaluate the prevalence of the CzIE in North American MSSA isolates. Clinical MSSA isolates from six microbiology laboratories in the United States and one microbiology laboratory in Canada were screened for the CzIE by broth microdilution at a standard inoculum (~5 × 105 CFU/mL) and a high inoculum (~5 × 107 CFU/mL). Genome sequencing was performed to further characterize the MSSA isolates. The CzIE was present in 57/305 (18.6%) MSSA isolates, ranging from 0% to 27.9% across study sites. More of the CzIE-positive isolates (29.8%) had standard inoculum cefazolin MICs of 1.0 µg/mL than the CzIE-negative isolates did (3.2%) (P < 0.0001). Conversely, more CzIE-negative isolates (39.5%) had standard inoculum MICs of 0.25 µg/mL than the CzIE positive isolates did (5.3%) (P < 0.0001). The most common BlaZ ß-lactamase types found in the CzIE-positive strains were type C (53.7%) and type A (44.4%). ST8 and ST30 were the most common sequence types among CzIE-positive isolates and correlated with BlaZ type C and A, respectively. The CzIE was present in up to a quarter of clinical MSSA isolates from North American clinical laboratories. Further studies to determine the impact of the presence of the CzIE on clinical outcomes are needed.
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Bacteriemia , Infecciones Estafilocócicas , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Bacteriemia/microbiología , Cefazolina/farmacología , Humanos , Meticilina , América del Norte , Prevalencia , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/genéticaRESUMEN
The cefazolin inoculum effect (CzIE) has been associated with therapeutic failures and mortality in invasive methicillin-susceptible Staphylococcus aureus (MSSA) infections. A diagnostic test to detect the CzIE is not currently available. We developed a rapid (â¼3 h) CzIE colorimetric test to detect staphylococcal-ß-lactamase (BlaZ) activity in supernatants after ampicillin induction. The test was validated using 689 bloodstream MSSA isolates recovered from Latin America and the United States. The cefazolin MIC determination at a high inoculum (107 CFU/ml) was used as a reference standard (cutoff ≥16 µg/ml). All isolates underwent genome sequencing. A total of 257 (37.3%) of MSSA isolates exhibited the CzIE by the reference standard method. The overall sensitivity and specificity of the colorimetric test was 82.5% and 88.9%, respectively. Sensitivity in MSSA isolates harboring type A BlaZ (the most efficient enzyme against cefazolin) was 92.7% with a specificity of 87.8%. The performance of the test was lower against type B and C enzymes (sensitivities of 53.3% and 72.3%, respectively). When the reference value was set to ≥32 µg/ml, the sensitivity for isolates carrying type A enzymes was 98.2%. Specificity was 100% for MSSA lacking blaZ The overall negative predictive value ranged from 81.4% to 95.6% in Latin American countries using published prevalence rates of the CzIE. MSSA isolates from the United States were genetically diverse, with no distinguishing genomic differences from Latin American MSSA, distributed among 18 sequence types. A novel test can readily identify most MSSA isolates exhibiting the CzIE, particularly those carrying type A BlaZ. In contrast to the MIC determination using high inoculum, the rapid test is inexpensive, feasible, and easy to perform. After minor validation steps, it could be incorporated into the routine clinical laboratory workflow.
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Cefazolina , Infecciones Estafilocócicas , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Cefazolina/farmacología , Pruebas Diagnósticas de Rutina , Humanos , América Latina , Meticilina , Pruebas de Sensibilidad Microbiana , Infecciones Estafilocócicas/diagnóstico , Infecciones Estafilocócicas/tratamiento farmacológico , Staphylococcus aureus/genéticaRESUMEN
Cefazolin has become a prominent therapy for methicillin-susceptible Staphylococcus aureus (MSSA) infections. However, an important concern is the cefazolin inoculum effect (CzIE), a phenomenon mediated by staphylococcal ß-lactamases. Four variants of staphylococcal ß-lactamases have been described based on serological methodologies and limited sequence information. Here, we sought to reassess the classification of staphylococcal ß-lactamases and their correlation with the CzIE. We included a large collection of 690 contemporary bloodstream MSSA isolates recovered from Latin America, a region with a high prevalence of the CzIE. We determined cefazolin MICs at standard and high inoculums by broth microdilution. Whole-genome sequencing was performed to classify the ß-lactamase in each isolate based on the predicted full sequence of BlaZ. We used the classical schemes for ß-lactamase classification and compared it to BlaZ allotypes found in unique sequences using the genomic information. Phylogenetic analyses were performed based on the BlaZ and core-genome sequences. The overall prevalence of the CzIE was 40%. Among 641 genomes, type C was the most predominant ß-lactamase (37%), followed by type A (33%). We found 29 allotypes and 43 different substitutions in BlaZ. A single allotype, designated BlaZ-2, showed a robust and statistically significant association with the CzIE. Two other allotypes (BlaZ-3 and BlaZ-5) were associated with a lack of the CzIE. Three amino acid substitutions (A9V, E112A, and G145E) showed statistically significant association with the CzIE (P = <0.01). CC30 was the predominant clone among isolates displaying the CzIE. Thus, we provide a novel approach to the classification of the staphylococcal ß-lactamases with the potential to more accurately identify MSSA strains exhibiting the CzIE.
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Antibacterianos/farmacología , Cefazolina/farmacología , Farmacorresistencia Bacteriana/genética , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/genética , beta-Lactamasas/clasificación , Bacteriemia/epidemiología , Bacteriemia/microbiología , Humanos , América Latina/epidemiología , Pruebas de Sensibilidad Microbiana , Epidemiología Molecular , Filogenia , Prevalencia , Infecciones Estafilocócicas/epidemiología , Staphylococcus aureus/enzimología , Secuenciación Completa del Genoma , beta-Lactamasas/genéticaRESUMEN
BACKGROUND: Lactococcus garvieae is an unusual cause of infective endocarditis (IE). No current diagnostic and therapeutic guidelines are available to treat IE caused by these organisms. Based on a case report, we provide a review of the literature of IE caused by L. garvieae and highlight diagnostic and treatment challenges of these infections and implications for management. CASE PRESENTATION: A 50-year-old Asian male with mitral prosthetic valve presented to the hospital with intracranial haemorrhage, which was successfully treated. Three weeks later, he complained of generalized malaise. Further work up revealed blood cultures positive for Gram-positive cocci identified as L. garvieae by MALDI-TOF. An echocardiogram confirmed the diagnosis of IE. Susceptibility testing showed resistance only to clindamycin. Vancomycin plus gentamicin were started as empirical therapy and, subsequently, the combination of ceftriaxone plus gentamicin was used after susceptibility studies were available. After two weeks of combination therapy, ceftriaxone was continued as monotherapy for six additional weeks with good outcome. CONCLUSIONS: Twenty-five cases of IE by Lactococcus garvieae have been reported in the literature. Compared to other Gram-positive cocci, L. garvieae affects more frequently patients with prosthetic valves. IE presents in a subacute manner and the case fatality rate can be as high as 16%, comparable to that of streptococcal IE (15.7%). Reliable methods for identification of L. garvieae include MALDI-TOF, 16S RNA PCR, API 32 strep kit and BD Automated Phoenix System. Recommended antimicrobials for L. garvieae IE are ampicillin, amoxicillin, ceftriaxone or vancomycin in monotherapy or in combination with gentamicin.
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Endocarditis Bacteriana/diagnóstico , Infecciones por Bacterias Grampositivas/diagnóstico , Lactococcus/aislamiento & purificación , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Ceftriaxona/farmacología , Ceftriaxona/uso terapéutico , Quimioterapia Combinada , Ecocardiografía , Endocarditis Bacteriana/tratamiento farmacológico , Endocarditis Bacteriana/microbiología , Gentamicinas/farmacología , Gentamicinas/uso terapéutico , Infecciones por Bacterias Grampositivas/tratamiento farmacológico , Infecciones por Bacterias Grampositivas/microbiología , Prótesis Valvulares Cardíacas , Humanos , Lactococcus/química , Lactococcus/efectos de los fármacos , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Vancomicina/farmacología , Vancomicina/uso terapéuticoRESUMEN
The cefazolin inoculum effect (CzIE) has been associated with poor clinical outcomes in patients with MSSA infections. We aimed to investigate the point prevalence of the CzIE among nasal colonizing MSSA isolates from ICU patients in a multicenter study in Colombia (2019-2023). Patients underwent nasal swabs to assess for S. aureus colonization on admission to the ICU and some individuals had follow-up swabs. We performed cefazolin MIC by broth-microdilution using standard and high-inoculum and developed a modified nitrocefin-based rapid test to detect the CzIE. Whole genome sequencing was carried out to characterize BlaZ types and allotypes, phylogenomics and Agr-typing. All swabs were subjected to 16S-rRNA metabarcoding sequencing to evaluate microbiome characteristics associated with the CzIE. A total of 352 patients were included; 46/352 (13%) patients were colonized with S. aureus; 22% (10/46) and 78% (36/46) with MRSA and MSSA, respectively. Among 36 patients that contributed with 43 MSSA colonizing isolates, 21/36 (58%) had MSSA exhibiting the CzIE. BlaZ type A and BlaZ-2 were the predominant type and allotype in 56% and 52%, respectively. MSSA belonging to CC30 were highly associated with the CzIE and SNP analyses supported transmission of MSSA exhibiting the CzIE among some patients of the same unit. The modified nitrocefin rapid test had 100%, 94.4% and 97.7% sensitivity, specificity and accuracy, respectively. We found a high prevalence point prevalence of the CzIE in MSSA colonizing the nares of critically-ill patients in Colombia. A modified rapid test was highly accurate in detecting the CzIE in this patient population.
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Carbapenem-resistant Klebsiella pneumoniae (CRKp) is an urgent public health threat. Worldwide dissemination of CRKp has been largely attributed to clonal group (CG) 258. However, recent evidence indicates the global emergence of a CRKp CG307 lineage. Houston, TX, is the first large city in the United States with detected cocirculation of both CRKp CG307 and CG258. We sought to characterize the genomic and clinical factors contributing to the parallel endemic spread of CG258 and CG307. CRKp isolates were collected as part of the prospective, Consortium on Resistance against Carbapenems in Klebsiella and other Enterobacterales 2 (CRACKLE-2) study. Hybrid short-read and long-read genome assemblies were generated from 119 CRKp isolates (95 originated from Houston hospitals). A comprehensive characterization of phylogenies, gene transfer, and plasmid content with pan-genome analysis was performed on all CRKp isolates. Plasmid mating experiments were performed with CG307 and CG258 isolates of interest. Dissection of the accessory genomes suggested independent evolution and limited horizontal gene transfer between CG307 and CG258 lineages. CG307 contained a diverse repertoire of mobile genetic elements, which were shared with other non-CG258 K. pneumoniae isolates. Three unique clades of Houston CG307 isolates clustered distinctly from other global CG307 isolates, indicating potential selective adaptation of particular CG307 lineages to their respective geographical niches. CG307 strains were often isolated from the urine of hospitalized patients, likely serving as important reservoirs for genes encoding carbapenemases and extended-spectrum ß-lactamases. Our findings suggest parallel cocirculation of high-risk lineages with potentially divergent evolution. IMPORTANCE The prevalence of carbapenem-resistant Klebsiella pneumoniae (CRKp) infections in nosocomial settings remains a public health challenge. High-risk clones such as clonal group 258 (CG258) are particularly concerning due to their association with blaKPC carriage, which can severely complicate antimicrobial treatments. There is a recent emergence of clonal group 307 (CG307) worldwide with little understanding of how this successful clone has been able to adapt while cocirculating with CG258. We provide the first evidence of potentially divergent evolution between CG258 and CG307 with limited sharing of adaptive genes. Houston, TX, is home to the largest medical center in the world, with a large influx of domestic and international patients. Thus, our unique geographical setting, where two pandemic strains of CRKp are circulating, provides an indication of how differential accessory genome content can drive stable, endemic populations of CRKp. Pan-genomic analyses such as these can reveal unique signatures of successful CRKp dissemination, such as the CG307-associated plasmid (pCG307_HTX), and provide invaluable insights into the surveillance of local carbapenem-resistant Enterobacterales (CRE) epidemiology.
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Enterobacteriaceae Resistentes a los Carbapenémicos , Infecciones por Klebsiella , Enterobacteriaceae Resistentes a los Carbapenémicos/genética , Carbapenémicos/farmacología , Humanos , Infecciones por Klebsiella/epidemiología , Klebsiella pneumoniae , Estudios ProspectivosRESUMEN
Stomach cancer (SC) incidence and mortality are relevant public health issues worldwide. In Colombia, screening for preneoplastic lesions (PNL) and the presence of H. pylori is not routinely performed. Therefore, the aim of this study was to evaluate OLGA-OLGIM staging and the interobserver agreement in gastritis and preneoplastic lesions in patients with gastroduodenal symptoms from Colombia. A cross-sectional study was conducted in 272 patients with gastroduodenal symptoms. Gastric biopsies were taken following the Updated Sydney System with the OLGA-OLGIM classification, and the results were evaluated by two pathologists. Chronic gastritis and PNL were reported in 76% and 24% of the patients, respectively. Furthermore, 25% of the patients with PNL displayed gastric atrophy (GA) and 75% intestinal metaplasia (IM). Agreement in the histopathological reading for IM was good, whereas for OLGA was variable, and for the H. pylori quantity was poor. OLGA-OLGIM stages 0-II were the most frequent (96%), while stage III (4%) and SC (4%) were the least frequent. Age and coffee consumption were associated with a higher prevalence of PNL. This work determined that 4% of the population is at high risk of developing SC and would benefit from follow-up studies. Reinforcement of training programs to improve the agreement in histopathology readings is required.
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Gastritis Atrófica , Gastritis , Infecciones por Helicobacter , Helicobacter pylori , Lesiones Precancerosas , Neoplasias Gástricas , Estudios Transversales , Gastritis/diagnóstico , Gastritis Atrófica/complicaciones , Gastritis Atrófica/diagnóstico , Gastritis Atrófica/patología , Infecciones por Helicobacter/complicaciones , Infecciones por Helicobacter/diagnóstico , Humanos , Metaplasia , Variaciones Dependientes del Observador , Lesiones Precancerosas/diagnóstico , Lesiones Precancerosas/patología , Factores de Riesgo , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/patologíaRESUMEN
A 19-year-old patient who mistakenly received two doses of influenza vaccine 10 days before presentation, was admitted with malaise, weakness, and a purpuric non-blanching rash most prominent on the ankles followed by abdominal pain and hematochezia 72h later. The diagnosis of influenza vaccine-related Henoch-Schonlein vasculitis was made. This complication, although rare, is the most common vasculitis related to immunization.
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Vasculitis por IgA/etiología , Vacunas contra la Influenza/efectos adversos , Glucocorticoides/uso terapéutico , Humanos , Vasculitis por IgA/tratamiento farmacológico , Masculino , Metilprednisolona/uso terapéutico , Prednisona/uso terapéutico , Vacunación/efectos adversos , Adulto JovenRESUMEN
Aim: To determine the frequency of Helicobacter pylori and sociodemographic factors, life habits, and personal and family history of gastroduodenal diseases in patients who required and were taken to GI endoscopy (symptomatic or by screening) in seven endoscopy units in three Antioquia subregions. Materials and methods: A cross-sectional study conducted between 2016 and 2018 included 272 participants. Sociodemographic factors, life habits, and personal and family history were related to H. pylori infection. Descriptive statistics and bivariate analysis were performed to establish the association between the variables, and multivariate analysis (binomial regression) was used to adjust the prevalence ratios of the associated factors. A p-value ≤ 0.05 was considered statistically significant. Results: The frequency of H. pylori infection was 55.9%, with differences by subregion (Valle de Aburrá metropolitan area: 54.3%, Oriente: 64%, and Urabá: 79.2%). Factors associated with H. pylori infection were male sex (adjusted prevalence ratio [APR] = 1.26; 95% confidence interval [CI] = 1.04-1.52), age 18-55 years (APR = 1.62; CI 95% = 1.22-2.16), absence of drinking water (APR = 1.40; 95% CI: 1.15-1.72) and educational level below university (APR = 1.73; 95% CI% = 1.26-2.38). Conclusion: The frequency of H. pylori was higher than in other recent studies because different diagnostic tests were used for its detection, and differences were found in the frequency of infection by region, which is explained by the heterogeneity in the populations analyzed. This study suggests the need to improve the population's living conditions to reduce H. pylori and direct measures of primary prevention of the infection, especially in family groups, men, individuals between 18 and 55 years old without drinking water, and with an educational level lower than university.
Objetivo: determinar la frecuencia de Helicobacter pylori y la presencia de factores sociodemográficos, hábitos de vida y antecedentes personales y familiares de enfermedades gastroduodenales en pacientes que requirieron y fueron llevados a endoscopia digestiva (sintomáticos o por tamización) en siete unidades de endoscopia de tres subregiones de Antioquia. Materiales y métodos: estudio transversal realizado entre 2016 y 2018 que incluyó a 272 participantes. Los factores sociodemográficos, hábitos de vida, antecedentes personales y familiares se relacionaron con la infección por H. pylori. Se realizó estadística descriptiva y análisis bivariado para establecer la asociación entre las variables y el análisis multivariado (regresión binomial) para ajustar las razones de prevalencia de los factores asociados. Un valor p ≤ 0,05 se consideró estadísticamente significativo. Resultados: la frecuencia de infección por H. pylori fue de 55,9%, con diferencias por subregión (área metropolitana del Valle de Aburrá: 54,3%, oriente: 64% y Urabá: 79,2%). Los factores asociados a la infección por H. pylori fueron sexo masculino (razón de prevalencia ajustada [RPA] = 1,26; intervalo de confianza [IC] del 95% = 1,04-1,52), edad de 18-55 años (RPA = 1,62; IC 95% = 1,22-2,16), ausencia de agua potable (RPA = 1,40; IC 95%: 1,15-1,72) y nivel educativo inferior al universitario (RPA = 1,73; IC 95% = 1,26-2,38). Conclusión: la frecuencia de H. pylori fue mayor que en otros estudios recientes porque se emplearon diferentes pruebas diagnósticas para su detección y se demostraron diferencias en la frecuencia de la infección por región, lo cual se explica por la heterogeneidad en las poblaciones analizadas. Este estudio sugiere la necesidad de mejorar las condiciones de vida de la población para reducir la infección por H. pylori y dirigir medidas de prevención primaria de la infección especialmente en los grupos familiares, en hombres, individuos entre 18 y 55 años, sin agua potable y con un nivel educativo inferior al universitario.
RESUMEN
ABSTRACT A 19-year-old patient who mistakenly received two doses of influenza vaccine 10 days before presentation, was admitted with malaise, weakness, and a purpuric non-blanching rash most prominent on the ankles followed by abdominal pain and hematochezia 72 h later. The diagnosis of influenza vaccine-related Henoch-Schonlein vasculitis was made. This complication, although rare, is the most common vasculitis related to immunization.