An Aminoglycoside-Sparing Regimen with Double Beta-Lactam to Successfully Treat Granulicatella adiacens Prosthetic Aortic Valve Endocarditis-Time to Change Paradigm?

(1) Background: Granulicatella adiacens is a former nutritionally variant streptococci (NVS). NVS infective endocarditis (IE) is generally characterized by a higher rate of morbidity and mortality, partially due to difficulties in choosing the most adequate microbiological culture method and the most effective treatment strategy, and partially due to higher rates of complications, such as heart failure, peripheral septic embolism, and peri-valvular abscess, as well as a higher rate of valve replacement. Depending on the affected valve (native valve endocarditisNVE, or prosthetic valve endocarditisPVE), the American Heart Association (AHA) 2015 treatment guidelines (GLs) suggest penicillin G, ampicillin, or ceftriaxone plus gentamicin (2 weeks for NVE and up to 6 weeks for PVE), while vancomycin alone may be a reasonable alternative in patients who are intolerant of ß-lactam therapy. The European Society of Cardiology (ESC) 2023 GLs recommend treating NVE with penicillin G, ceftriaxone, or vancomycin for 6 weeks, suggesting combined with an aminoglycoside (AG) for at least the first 2 weeks only for PVE; likewise, the same recommendations for IE due to Enterococcus faecalis. (2) Methods: Starting from the case of a 51-year-old man with G. adiacens aortic bio-prosthesis IE who was successfully treated with aortic valve replacement combined with double beta-lactams, an AG-sparing regimen, we performed microbiology tests in order to validate this potential treatment change. (3) Results: As for E. faecalis IE, we found that the combination of ampicillin plus cephalosporines (like ceftriaxone or ceftobiprole) showed a synergistic effect in vitro, probably due to wider binding to penicillin-binding proteins (PBPs), thus contributing to enhanced bacterial killing and good clinical outcome, as well as avoiding the risk of nephrotoxicity due to AG association therapy. (4) Conclusions: Further studies are required to confirm this hypothesis, but double beta-lactams and an adequate sourcecontrol could be a choice in treating G. adiacens IE.

Case series of infective endocarditis caused by Granulicatella species.

BACKGROUND: Nutritionally variant streptococci (NVS) are Gram-positive cocci characterized by their dependence on pyridoxal or cysteine supplementation for growth in standard blood culture media. They are responsible for severe infections in immunocompetent and immunosuppressed hosts, including infective endocarditis (IE). NVS have been divided into two different genera, Granulicatella and Abiotrophia. METHODS: We report four cases of IE caused by Granulicatella species, including clinical presentation, echocardiographic characteristics, treatments received, and outcomes. We also performed a literature search for previously reported cases of IE caused by Granulicatella species to better characterize this condition. RESULTS: A total of 29 cases of Granulicatella endocarditis were analyzed, including the four newly reported cases. The aortic (44%) and mitral (38%) valves were those most commonly affected. Multivalvular involvement was observed in 13% of cases. The mean vegetation length was 16mm. Complications were frequent, including heart failure (30%), embolism (30%), and perivalvular abscess (11%). The most frequent antibiotic regimen (85%) was penicillin or one of its derivatives plus gentamicin. The mortality rate was 17%. CONCLUSIONS: Endocarditis due to Granulicatella species is a rare and severe condition. Complications are frequent despite the use of appropriate antibiotic regimens.

Microbiología clínica: nuevos desafíos / Clinical microbiology: mew challenges

Si partimos de que la microbiología es una ciencia fundante, podemos estar de acuerdo también en la necesidad de la continua actualización de sus contenidos y su vinculación con la odontología. Nuevas técnicas de diagnóstico permiten, no solo poder identificar características especiales de cada microorganismo y su reubicación en la taxonomía general, sino también habilitan a reconocer a aquellos ­hasta el momento­ desconocidos en la cotidianeidad de la práctica profesional y que revisten importancia por sus afecciones sistémicas ya que pueden transformar, en algunos casos, a que el paciente sea considerado de riesgo. En este trabajo, se abordan tres ejemplares bacterianos seleccionados por su complejidad en la identificación y por la magnitud de las lesiones que producen. Granulicatella spp., Kingela kingae y Bilophila wadsworthia afectan no solo adultos sino también pacientes pediátricos, siendo afectados por patologías severas. Se describen cuadros clínicos que afectan tejido óseo, corazón, cerebro, hígado, bazo, riñón y las manifestaciones orales a las cuales pueden asociarse grupos microbianos que agravan el pronóstico. Aplicar la tecnología adecuadamente, no solo a procedimientos odontológicos, sino también para diagnóstico (PCR ­ MALDI ­ TOF) facilita la detección e identificación con mayor celeridad de estos agentes microbianos, evitando la rotación farmacológica, la resistencia microbiana y la automedicación (AU)

Considering microbiology as a key science in the approach of infectious processes, we understand the need for a continuous update of its contents and its link with dentistry. The incorporation of new technological approaches, such as molecular methods or mass spectrometry, allow us not only to identify special characteristics of the microorganism and its relocation in taxonomy, but also to know those microorganisms until now unknown in professional´s life everyday practice and that are important for their systemic implications, modifying in some cases, the risk assessment of the patient. Three bacterial specimens are developed in this work, due to their complexity in the identification and the magnitude of the lesions they produce, Granulicatella spp., Kingela kingae and Bilophila wadsworthia. These affects both adult and paediatric patients, describing several clinical conditions that affect bone tissue, heart, brain, liver, spleen, kidney and oral manifestations to which these microbial groups can be associated, aggravating the prognosis. Applying new technology, not only to dental procedures but also to diagnosis, facilitates the detection and identification with greater speed of these microbial agents, avoiding pharmacological rotation, microbial resistance and self-medication (AU)