Carlos González-Corralejo

The emergence of carbapenemase-producing Aeromonas species represents a growing concern due to their potential role as reservoirs and disseminators of antimicrobial resistance genes in aquatic and clinical environments. In this study, we describe the genomic characterization of a clinical Aeromonas caviae isolate harboring a plasmid-encoded KPC-type carbapenemase. This microorganism was isolated from a stool sample from a patient with acute gastroenteritis in May 2025. Whole-genome sequencing followed by bioinformatic analysis using ResFinder, PlasmidFinder, and MobileElementFinder revealed the presence of the blaKPC-2 gene located on an IncP-6 plasmid. The plasmid carried multiple insertion sequences and composite transposons, including IS26, ISKpn3, and IS6100, suggesting a highly mobile genetic platform. Comparative analysis indicates that the plasmid structure resembles previously reported KPC-harboring plasmids found in Enterobacterales, highlighting potential interspecies transfer events. To our knowledge, this is one of the few reports describing an IncP-6 plasmid carrying blaKPC-2 in Aeromonas caviae. These findings underscore the importance of environmental and clinical surveillance of carbapenemase-producing bacteria.

Respiratory syncytial virus (RSV) infection is one of the main causes of morbidity and mortality in infants under 6 months of age; however, it can cause respiratory infection at other stages of life. In the period 2018-2025, the number of cases has risen considerably, with positivity mainly concentrated in children under 24 months of age. The SARS-CoV2 pandemic caused modifications in affected population groups and seasonality. The percentage of RSV in children under 6 months of age in the period 2024-2025 was significantly lower than in the 2023-2024 season. In contrast, in the elderly population, especially those over 86 years of age, the percentage of positive cases has increased significantly. From 2022 onwards, the incidence of virus positivity shows a more stable and sustained pattern from October to April compared to previous years. The aim of this review is to assess the evolution of the type of patient diagnosed with RSV infection and to determine early whether the beginning of the vaccination campaign has reduced the incidence in the susceptible population. The availability of epidemiological information to guide decision-making is of great importance for evaluating the effectiveness of these measures and adopting changes in the use of vaccination in the general population.

Pneumonia is the leading cause of death from infection in the developed world. In recent years, researchers and healthcare professionals have worked extensively to reduce this burden. Prevention is better than cure, and significant advances have been made in areas such as vaccination and the prevention of nosocomial pneumonia in intensive care units. Comprehensive surveillance programmes and new diagnostic methods have been developed to assess trends in this disease and to identify the infectious agents involved. Clinical presentation can be challenging in elderly patients or those with certain comorbidities, prompting new studies in these populations to address these issues. Correct and early management of severe community-acquired pneumonia represents a major opportunity to reduce its associated mortality. Although fungal pathogens are an uncommon cause of lung infection, they are associated with high morbidity and mortality, highlighting the need for new approaches. Finally, new drugs are available for the treatment of pneumonia, and a thorough understanding of them is key to ensuring their correct use, particularly to combat multi-resistance. To provide an update on these points, a multidisciplinary team of Spanish experts convened at the Sixth Annual Meeting of Pneumonia Day, under the scientific sponsorship of GEIPC-SEIMC. This paper reflects the information shared at this meeting, offering the latest insights on these topics and supporting a holistic approach to pneumonia management.

Pneumonia is a multifaceted illness with a wide range of clinical manifestations, degree of severity and multiple potential causing microorganisms. Despite the intensive research of recent decades, community-acquired pneumonia remains the third-highest cause of mortality in developed countries and the first due to infections; and hospital-acquired pneumonia is the main cause of death from nosocomial infection in critically ill patients. Guidelines for management of this disease are available worldwide, but there are questions which generate controversy, and the latest advances make it difficult to stay them up to date. A multidisciplinary approach can overcome these limitations and can also aid to improve clinical results. Spanish medical societies involved in diagnosis and treatment of pneumonia have made a collaborative effort to actualize and integrate last expertise about this infection. The aim of this paper is to reflect this knowledge, communicated in Fifth Pneumonia Day in Spain. It reviews the most important questions about this disorder, such as microbiological diagnosis, advances in antibiotic and sequential therapy, management of beta-lactam allergic patient, preventive measures, management of unusual or multi-resistant microorganisms and adjuvant or advanced therapies in Intensive Care Unit.

Despite the well‐known hepatoprotective role of the epidermal growth factor receptor (EGFR) pathway upon acute damage, its specific actions during chronic liver disease, particularly cholestatic injury, remain ambiguous and unresolved. Here, we analyzed the consequences of inactivating EGFR signaling in the liver on the regenerative response following cholestatic injury. For that, transgenic mice overexpressing a dominant negative mutant human EGFR lacking tyrosine kinase activity (ΔEGFR) in albumin‐positive cells were submitted to liver damage induced by 3,5‐diethoxycarbonyl‐1,4‐dihydrocollidine (DDC), an experimental model resembling human primary sclerosing cholangitis. Our results show an early activation of EGFR after 1–2 days of a DDC‐supplemented diet, followed by a signaling switch‐off. Furthermore, ΔEGFR mice showed less liver damage and a more efficient regeneration following DDC injury. Analysis of the mechanisms driving this effect revealed an enhanced activation of mitogenic/survival signals, AKT and ERK1/2‐MAPKs, and changes in cell turnover consistent with a quicker resolution of damage in response to DDC. These changes were concomitant with profound differences in the profile of intrahepatic immune cells, consisting of a shift in the M1/M2 balance towards M2 polarity, and the Cd4/Cd8 ratio in favor of Cd4 lymphocytes, overall supporting an immune cell switch into a pro‐restorative phenotype. Interestingly, ΔEGFR livers also displayed an amplified ductular reaction, with increased expression of EPCAM and an increased number of CK19‐positive ductular structures in portal areas, demonstrating an overexpansion of ductular progenitor cells. In summary, our work supports the notion that hepatocyte‐specific EGFR activity acts as a key player in the crosstalk between parenchymal and non‐parenchymal hepatic cells, promoting the pro‐inflammatory response activated during cholestatic injury and therefore contributing to the pathogenesis of cholestatic liver disease. © 2022 The Pathological Society of Great Britain and Ireland.