Clinical and Microbiological Analysis of Hospital-Acquired Pneumonia Among Patients With Ischemic Stroke: A Retrospective Outlook

Role of the gut microbiota in complications after ischemic stroke

Ischemic stroke (IS) is a serious central nervous system disease. Post-IS complications, such as post-stroke cognitive impairment (PSCI), post-stroke depression (PSD), hemorrhagic transformation (HT), gastrointestinal dysfunction, cardiovascular events, and post-stroke infection (PSI), result in neurological deficits. The microbiota-gut-brain axis (MGBA) facilitates bidirectional signal transduction and communication between the intestines and the brain. Recent studies have reported alterations in gut microbiota diversity post-IS, suggesting the involvement of gut microbiota in post-IS complications through various mechanisms such as bacterial translocation, immune regulation, and production of gut bacterial metabolites, thereby affecting disease prognosis. In this review, to provide insights into the prevention and treatment of post-IS complications and improvement of the long-term prognosis of IS, we summarize the interaction between the gut microbiota and IS, along with the effects of the gut microbiota on post-IS complications.

Clinical and Etiological Exploration of Ventilator-Associated Pneumonia in the Intensive Care Unit of a Developing Country

Background Ventilator-associated pneumonia (VAP) is a critical concern in the intensive care unit (ICU), with significant implications for patient outcomes. This retrospective cross-sectional study aimed to determine the prevalence of VAP in an ICU of a developing country, identify the predominant etiological factors, assess patient outcomes, and underscore the need for tailored interventions in high-risk patient groups. Methods This retrospective cross-sectional study included 589 ICU patients who underwent ventilator-assisted breathing for over 48 hours. Among them, 151 developed VAP. The diagnosis was made on clinical, laboratory, and radiological findings, and tracheal aspirate cultures. Exclusions included pediatric patients, less than 48 hours of ventilation, and pre-existing lung infections. Patient data encompassed gender, age, comorbidities, outcomes, admission reasons, isolated microorganisms, and clinical findings. Results 151 patients out of the 589 developed VAP. The age of the patients ranged between 31 to 69 years and the mean age was 45.43 ± 8.92 years. Clinical diagnoses upon ICU admission varied, including sepsis, trauma, stroke, and metabolic disorders. Chest X-rays commonly revealed atelectasis (19.2%), consolidation (21.9%), pleural effusion (11.9%), and lobar pneumonia (45.7%). Tracheal aspirate cultures predominantly isolated multidrug-resistant gram-negative rods, with methicillin-resistant gram-positive cocci and fungal pneumonia prevalent in neutropenic sepsis cases. Notably, only 54 (35.8%) of patients survived, with significantly poorer outcomes observed in sepsis, neutropenic sepsis, and stroke cases compared to trauma and post-operative admissions. Conclusion Multidrug-resistant organisms and the spread of nosocomial infections are the predominant causes of VAP in the ICU. This emphasizes the urgent need for multifaceted interventions to prevent and manage VAP effectively. Developing and implementing targeted strategies, considering the unique challenges faced in resource-constrained healthcare settings can aid in decreasing the mortality associated with it.

Distribution of bacteria and risk factors in patients with multidrug-resistant pneumonia in a single center rehabilitation ward

Stroke patients may have dysphagia and frequent aspiration increasing exposure to antibiotics and the chance of multidrug-resistant (MDR) bacteria infection. This study investigated clinical risk factors and related antibiotic use of MDR bacteria infection in stroke patients in the rehabilitation ward, hoping that it can help prevent and reduce the condition of MDR bacteria. A retrospective cohort study was conducted using the database of stroke patients with pneumonia admitted to the rehabilitation ward from January 1, 2020, to June 30, 2022. The selected stroke patients were divided into the MDR and non-MDR groups. Analyze the infection bacteria of the 2 groups. Forward logistic regression was applied to identify possible independent MDR bacteria infection risk factors. A total of 323 patients were included. The top 3 common MDR pathogens were Pseudomonas aeruginosa, Klebsiella pneumoniae, and Acinetobacter baumannii. Almost all Pseudomonas aeruginosa and Acinetobacter baumannii are resistant to ertapenem. National Institute of Health stroke scale at admission was associated with MDR bacteria infection pneumonia (OR [odds ratio] = 1.078, 95%CI [1.017, 1.142]). Long-term tracheotomy (OR = 2.695, 95%CI [1.232, 5.897]), hypoalbuminemia (OR = 473, 95%CI [1.318, 4.642]), and bilateral cerebral hemisphere stroke (OR = 4.021, 95%CI [2.009, 8.048]) were significant clinical risk factors of MDR pneumonia after stroke. The detection rate of MDR bacteria has increased. Understanding the distribution and drug resistance of MDR bacteria in stroke patients with pneumonia in the neurological rehabilitation ward and the related susceptibility of MDR bacteria infection is necessary. This way, the treatment plan can be adjusted more timely, avoiding the abuse of antibiotics.

Dynamic Process of Secondary Pulmonary Infection in Mice With Intracerebral Hemorrhage

Stroke is a common central nervous system disease in clinical practice. Stroke patients often have infectious complications, such as pneumonia and infections of the urinary tract and gastrointestinal tract. Although it has been shown that translocation of the host gut microbiota to the lungs and immune dysfunction plays a vital role in the development of infection after ischemic stroke, the occurrence and mechanism of pulmonary infection at different time points after hemorrhagic cerebral remain unclear. In this study, the changes in the immune system and intestinal barrier function in mice during disease development were investigated at 1 day (M 1 d), 3 days (M 3 d) and 7 days (M 7 d) following hemorrhagic stroke to clarify the mechanism of secondary pulmonary infection. The experimental results revealed that after hemorrhagic stroke, model mice showed increased brain damage from day 1 to 3, followed by a trend of brain recovery from day 3 to 7 . After hemorrhagic stroke, the immune system was disturbed in model mice. Significant immunosuppression of the peripheral immune system was observed in the M 3 d group but improved in the M 7 d group. Staining of lung tissues with hematoxylin and eosin (H&E) and for inflammatory factors revealed considerable disease and immune disorders in the M 7 d group. Stroke seriously impaired intestinal barrier function in mice and significantly changed the small intestine structure. From 1 to 7 d after stroke, intestinal permeability was increased, whereas the levels of markers for intestinal tight junctions, mucus and immunoglobulin A were decreased. Analysis based on 16S rRNA suggested that the microflora in the lung and ileum was significantly altered after stroke. The composition of microflora in lung and ileum tissue was similar in the M 7d group, suggesting that intestinal bacteria had migrated to lung tissue and caused lung infection at this time point after hemorrhagic stroke. In stroke mice, the aggravation of intestinal barrier dysfunction and immune disorders after intracerebral hemorrhage, promoted the migration of enteric bacteria, and increased the risk of pneumonia poststroke. Our findings reveal the dynamic process of infection after hemorrhagic stroke and provide clues for the optimal timing of intervention for secondary pulmonary infection in stroke patients.