Differentiating lung neuroendocrine neoplasms from tumor-like infection using CT in patients with ectopic ACTH syndrome.

OBJECTIVES: Pulmonary neuroendocrine neoplasms (NENs) are the most frequent cause of ectopic adrenocorticotropic hormone syndrome (EAS); lung infection is common in EAS. An imaging finding of infection in EAS patients can mimic NENs. This retrospective study investigated EAS-associated pulmonary imaging indicators. METHODS: Forty-five pulmonary NENs and 27 tumor-like infections from 59 EAS patients (45 NEN and 14 infection patients) were included. Clinical manifestations, CT features, 18F-FDG, or 68Ga-DOTATATE-PET/CT images and pathological results were collected. RESULTS: High-sensitivity C-reactive protein (p < 0.001) and expectoration occurrence (p = 0.04) were higher, and finger oxygen saturation (p = 0.01) was lower in the infection group than the NENs group. Higher-grade NENs were underrepresented in our cohort. Pulmonary NENs were solitary primary tumors, 80% of which were peripheral tumors. Overlying vessel sign and airway involvement were more frequent in the NENs group (p < 0.001). Multifocal (p = 0.001) and peripheral (p = 0.02) lesions, cavity (p < 0.001), spiculation (p = 0.01), pleural retraction (p < 0.001), connection to pulmonary veins (p = 0.02), and distal atelectasis or inflammatory exudation (p = 0.001) were more frequent in the infection group. The median CT value increment between the non-contrast and arterial phases was significantly higher in NENs lesions (p < 0.001). Receiver operating characteristic curve analysis indicated a moderate predictive ability at 48.3 HU of delta CT value (sensitivity, 95.0%; specificity, 54.1%). CONCLUSION: Chest CT scans are valuable for localizing and characterizing pulmonary lesions in rare EAS, thereby enabling prompt differential diagnosis and treatment. CRITICAL RELEVANCE STATEMENT: Thin-slice CT images are valuable for the localization and identification of pulmonary ectopic adrenocorticotropic hormone syndrome lesions, leading to prompt differential diagnosis and effective treatment. KEY POINTS: Lung tumor-like infections can mimic neuroendocrine neoplasms (NENs) in ectopic adrenocorticotropic hormone syndrome (EAS) patients. NENs are solitary lesions, whereas infections are multiple peripheral pseudotumors each with identifying imaging findings. Typical CT signs aid in localization and creating an appropriate differential diagnosis.

Case report: Rare pulmonary fungal infection caused by Penicillium digitatum: the first clinical report in China.

Penicillium digitatum is a common plant pathogen that causes citrus rot, which is extremely rare in humans. We report a case of a 66-year-old man with a history of consuming large amounts of citrus fruits, smoking for 30 years, and a history of emphysema. He had experienced intermittent coughing with sputum for more than 10 years and was admitted to the hospital due to worsening of symptoms over the past month. Despite antibiotic treatment, his condition did not improve. Subsequently, bronchoalveolar lavage fluid (BALF) was detected by metagenomic next-generation sequencing (mNGS), which showed the presence of P. digitatum. The fungal culture of BALF also indicated the presence of the Penicillium genus. The diagnosis was lung infection caused by P. digitatum, and the patient was treated with itraconazole. The lung infection was controlled. This is the third reported case of invasive pulmonary fungal infection caused by P. digitatum worldwide at the genus level, and the first reported case in China. Although human infections caused by P. digitatum are rare, as an emerging opportunistic pathogen, the detection of this fungus in immunocompromised patients should still be clinically important.

Yersinia pestis and pneumonic plague: Insight into how a lethal pathogen interfaces with innate immune populations in the lung to cause severe disease.

Yersinia pestis is the causative agent of bubonic, septicemic and pneumonic plague. The historical importance and potential of plague to re-emerge as a threat worldwide are indisputable. The most severe manifestion of plague is pneumonic plague, which results in disease that is 100% lethal without treatment. Y. pestis suppresses host immune responses early in the lung to establish infection. The later stages of infection see the rapid onset of hyperinflammatory responses that prove lethal. The study of Y. pestis host/pathogen interactions have largely been investigated during bubonic plague and with attenuated strains in cell culture models. There remains a somewhat limited understanding of the interactions between virulent Y. pestis and immune populations in the lung that drive severe disease. In this review we give a broad overview of the progression of pneumonic plague and highlighting how Y. pestis interfaces with host innate immune populations in the lung to cause lethal disease.

A case of treatment for pulmonary infection caused by multidrug-resistant Acinetobacter baumannii.

Acinetobacter baumannii is a major pathogen in hospital-acquired infections notorious for its strong acquired resistance and complex drug resistance mechanisms. Owing to the lack of effective drugs, the mortality rate of extensively drug-resistant A. baumannii pneumonia can reach as high as 65%. This article analyzes a case where a combination of cefoperazone-sulbactam, polymyxin B, and minocycline with rifampicin successfully treated XDR-AB pulmonary infection. Combination therapy is effective and has a particular clinical value.

Metagenomic next-generation sequencing assistance in identifying Mycobacterium iranicum pulmonary infection: A case report.

Nontuberculous mycobacteria (NTM) are important opportunistic pathogens in humans, mostly affecting the lungs, and potentially causing progressive disease in individuals with underlying diseases. The prevalence of NTM infections is increasing worldwide. However, Mycobacterium iranicum (M. iranicum) infections are less common. Here we report a 65-year-old female who developed pneumonia caused by Mycobacterium iranicum, which was detected in bronchoalveolar lavage fluid (BALF) through metagenomic next-generation sequencing (mNGS). The patient was treated with moxifloxacin, doxycycline, and sulfamethoxazole/trimethoprim. Symptoms were relieved and lung abnormalities were shown to be partially absorbed on the follow-up chest computed tomography (CT) scans. As we know, this is the first case of Mycobacterium iranicum pulmonary infection identified by mNGS in BALF.

Risk factors for pulmonary infection in patients with non-small cell lung cancer: a Meta-analysis.

BACKGROUND AND OBJECTIVES: The aim of this study is to assess and examine the risk variables associated with pulmonary infections in non-small cell lung cancer (NSCLC) and to offer evidence-based recommendations for clinical prophylaxis. METHODS: Up to December 2023, database such as CNKI, Wanfang, VIP Chinese Science and Technology Journals, Chinese Biomedical, Pubmed, Web of science, and the Cochrane library were searched in order to find randomized controlled trials pertaining to non-small cell lung cancer complicated by pulmonary infection. The NOS scale was utilized to assess the quality of the included research, and the Q test findings were utilized to ascertain the degree of heterogeneity among the studies. RESULTS: After retrieving 957 studies in total, 10 literatures were ultimately included for additional analysis. Diabetes mellitus [OR, 2.89; 95% CI: 1.85-4.52; P < 0.00001)] hypoalbuminemia, radiotherapy [OR, 0.43; 95% CI: 1.89-4.07; P < 0.00001], and surgical duration exceeding 180 min [OR,1.10 (1.10 ~ 5.38); P = 0.03] were found to be risk factors for lung infection. Nevertheless, in NSCLC patients, pulmonary infection was not significantly correlated with factors such as age [OR, -0.16 (-0.96 ~ 0.64); P = 0.69], sex [OR, 1.08 (0.77 ~ 1.51); P = 0.66], smoking [OR, 1.10 (0.61 ~ 2.00); P = 0.75], adenocarcinoma [OR,1.10 (0.55 ~ 2.22); P = 0.79], OR, 1.08; 95% CI: 0.77-1.51; P = 0.66], TNMIII-IV stages [OR, 1.62; 95% CI: 0.96-2.75; P = 0.07], and hypertension [1.01(0.76 ~ 1.34); P = 0.94]. CONCLUSION: Diabetes mellitus, radiation therapy, and longer than 180-minute surgeries are risk factors for lung infection in NSCLC patients. The incidence of lung infection can be reduced by quickly identifying these risk factors and putting preventive measures in place.

Dual tobramycin and docosahexaenoic acid loaded nanoemulsions combating Pseudomonas aeruginosa-induced pulmonary infection.

Pseudomonas aeruginosa (P. aeruginosa) typically forms biofilms in vivo, which exhibit high resistance and complicate eradication efforts. Additionally, persistent inflammation and excessive oxidative stress can lead to severe lung dysfunction, facilitating bacterial colonization and infection. Herein, we prepared oil-in-water (O/W) nanoemulsions (TD-αT NEs) by using PEG5k-block-PCL5k and α-tocopherol to encapsulate tobramycin (TOB). To enhance TOB's drug load, a hydrophobic ion pair (TDIP) composed of TOB and docosahexaenoic acid (DHA) was pre-prepared. TD-αT NEs was not only easily prepared and aerosolized, but stable in both physics and chemistry. The negatively charged TD-αT NEs facilitated penetration through mucus, reaching infection sites. Subsequently, TD-αT NEs permeated biofilms due to their small size and released drugs via lipase-triggered carrier dissociation, aiding in eradicating internal bacteria within biofilms (with a 16-fold reduction in CFU vs. free TOB group). TD-αT NEs simultaneously exerted superior anti-inflammatory effects, reducing levels of pro-inflammatory cytokines (NO, IL-6, IL-8, and TNF-α) while increasing the level of anti-inflammatory cytokine (IL-10). It was achieved through the upregulation of PPAR-γ and downregulation of NF-κB signaling, thus mitigating the lung damage. In addition, TD-αT NEs demonstrated strong antioxidant activity, alleviating the oxidative stress induced by P. aeruginosa. Notably, when administered via inhalation, TD-αT NEs significantly reduced the lung bacterial burden, lung inflammation, and oxidative stress in vivo compared to TOB solution. TD-αT NEs could prove beneficial in treating chronic pulmonary infections induced by P. aeruginosa through a comprehensive strategy, specifically enhancing biofilm eradication, reducing inflammation, and alleviating oxidative stress.

Construction of a prediction model for pulmonary infection and its risk factors in Intensive Care Unit patients.

Objective: To identify independent risk factors of pulmonary infection in intensive care unit (ICU) patients, and to construct a prediction model. Methods: Medical data of 398 patients treated in the ICU of Jiaxing Hospital of Traditional Chinese Medicine from January 2019 to January 2023 were analyzed. Univariate and multivariate logistic regression analyses were used to identify independent risk factors for pulmonary infection in ICU patients. R software was used to construct a nomogram prediction model, and the prediction model was internally validated using computer simulation bootstrap method. Predictive value of the model was analyzed using the receiver operating characteristic (ROC) curve. Results: A total of 97 ICU patients (24.37%) developed pulmonary infection. Age, ICU stay time, invasive operation, diabetes, duration of mechanical ventilation, and state of consciousness were all identified as risk factors for pulmonary infection. The calibration curve of the constructed nomogram prediction model showed a good consistency between the predicted value of the model and the actual observed value. ROC curve analysis showed that the area under the curve (AUC) of the model was 0.784 (95% CI: 0.731-0.837), indicating a certain predictive value. Conclusions: Age, length of stay in ICU, invasive operation, diabetes, duration of mechanical ventilation, and state of consciousness are risk factors for pulmonary infection in ICU patients. The nomogram prediction model constructed based on the above risk factors has shown a good predictive value.

Coinfection of Cedecea lapagei and Aspergillus sydowii detected in bronchoalveolar lavage fluid of a patient with pulmonary infection using metagenomic next-generation sequencing: A case report.

Background: Cedecea lapagei (C. lapagei), as a potential human pathogen, has been reported in limited cases of human infections in medical literature. However, the increasing frequency of isolating Cedecea lapagei from clinical specimens underscores its growing clinical significance that should not be underestimated. Aspergillus sydowii (A. sydowii), commonly isolated from various environments, serves as a pathogen of human cryptic aspergillosis. Clinical pathological changes caused by A. sydowii are not obvious, posing a significant challenge in clinical diagnosis. Consequently, metagenomic next-generation sequencing (mNGS) are required for precise differentiation and identification of pathogens. Case description: Here we present a case demonstrating successful treatment outcome in a patient with pulmonary infection caused by coinfection of C. lapagei and A. sydowii, as identified through metagenomic next-generation sequencing. The patient, a 50-year-old male, presented with worsening cough, sputum production, and hemoptysis. Metagenomic next-generation sequencing (mNGS) analysis of the bronchoalveolar lavage fluid (BALF) revealed the presence of both C. lapagei and A. sydowii. Subsequently, C. lapagei was also detected by culture in the same BALF sample, however while clinical fungal cultures and (1-3)-ß-D glucan testing yielded negative results. Based on these findings along with imaging features and clinical symptoms of the patient, the final diagnosis was determined to be a co-infection of C. lapagei and A. sydowii. Conclusion: The clinical manifestations of human infections caused by C. lapagei are not specific; patients with cryptic aspergillosis may have been previously overlooked due to improper specimen selection or negative routine tests. Therefore, precise identification of pathogens is crucial. This case report highlights the value of mNGS in detecting C. lapagei and A. sydowii in BALF, enabling timely diagnosis with coinfections.

Phenotypical characteristics of nontuberculous mycobacterial infection in patients with bronchiectasis.

BACKGROUND: The global mortality and morbidity rates of bronchiectasis patients due to nontuberculous mycobacteria (NTM) pulmonary infection are on a concerning upward trend. The aims of this study to identify the phenotype of NTM-positive individuals with bronchiectasis. METHODS: A retrospective single-center observational study was conducted in adult patients with bronchiectasis who underwent bronchoscopy in 2007-2020. Clinical, laboratory, pulmonary function, and radiological data were compared between patients with a positive or negative NTM culture. RESULTS: Compared to the NTM-negative group (n=677), the NTM-positive group (n=94) was characterized (P ≤0.05 for all) by older age, greater proportion of females, and higher rates of gastroesophageal reflux disease and muco-active medication use; lower body mass index, serum albumin level, and lymphocyte and eosinophil counts; lower values of forced expiratory volume in one second, forced vital capacity, and their ratio, and lower diffusing lung capacity for carbon monoxide; higher rates of bronchiectasis in both lungs and upper lobes and higher number of involved lobes; and more exacerbations in the year prior bronchoscopy. On multivariate analysis, older age (OR 1.05, 95% CI 1.02-1.07, P=0.001), lower body mass index (OR 1.16, 95% CI 1.16-1.07, P <0.001), and increased number of involved lobes (OR 1.26, 95% CI 1.01-1.44, P=0.04) were associated with NTM infection. CONCLUSIONS: Patients with bronchiectasis and NTM pulmonary infection are more likely to be older and female with more severe clinical, laboratory, pulmonary function, and radiological parameters than those without NTM infection. This phenotype can be used for screening patients with suspected NTM disease.

Predictors of treatment failure following early antibiotic discontinuation in culture-negative, ventilator-associated pneumonia: an observational study.

INTRODUCTION: Early antibiotic discontinuation in clinically suspected ventilator-associated pneumonia (VAP) may lead to infection relapse/recurrence and increase mortality. This study aimed to evaluate the incidence and potential predictors of treatment failure with this approach. METHODOLOGY: A retrospective observational study was conducted between September 2014 and November 2016 in a mixed intensive care unit. We included clinically suspected VAP patients whose quantitative sputum cultures from endotracheal aspirate were negative, allowing antibiotic discontinuation within 24 hours. Patients were monitored for signs and symptoms of recurrent VAP. Incidence and risk factors for treatment failure, defined as pneumonia recurrence, were determined using univariate logistic regression analysis and receiver operating characteristic (ROC) curves. RESULTS: Forty-three patients met the inclusion criteria. The incidence of treatment failure among culture-negative VAP following early antibiotic discontinuation was 27.9% (12 patients). There were no significant differences in procalcitonin levels, leukocyte counts or body temperature between the two groups, except for the modified clinical pulmonary infection score (mCPIS) (5.42 ± 2.19 versus 3.9 ± 1.54, p = 0.014). Procalcitonin levels at VAP diagnosis and antibiotic cessation both showed low predictive capacity for treatment failure (AUC 0.56, CI 95% 0.36-0.76 and AUC 0.57, CI 95% 0.37-0.76, respectively). However, combining mCPIS with procalcitonin improved the predictive value for treatment failure (AUC 0.765, CI 95% 0.56-0.96). CONCLUSIONS: Early antibiotic discontinuation may lead to a high incidence of treatment failure among culture-negative VAP patients. Procalcitonin alone should not guide antibiotic discontinuation decisions while combining mCPIS and procalcitonin enhances predictive accuracy for treatment failure.

Surfactant protein A modulates neuroinflammation in adult mice upon pulmonary infection.

BACKGROUND: One of the most common entry gates for systemic infection is the lung. In humans, pulmonary infections can lead to significant neurological impairment, ranging from acute sickness behavior to long-term disorders. Surfactant proteins (SP), essential parts of the pulmonary innate immune defense, have been detected in the brain of rats and humans. Recent evidence suggests that SP-A, the major protein component of surfactant, also plays a functional role in modulating neuroinflammation. This study aimed to determine whether SP-A deficiency affects the inflammatory response in the brain of adult mice during pulmonary infection. EXPERIMENTAL PROCEDURE: Adult male wild-type (WT, n = 72) and SP-A-deficient (SP-A-/-, n = 72) mice were oropharyngeally challenged with lipopolysaccharide (LPS), Pseudomonas aeruginosa (P. aeruginosa), or PBS (control). Both, behavioral assessment and subsequent brain tissue analysis, were performed 24, 48, and 72 h after challenge. The brain concentrations of the pro-inflammatory cytokines TNF-α, IL-6, and IL-1ß were determined by ELISA. Quantitative rtPCR was used to detect SP-A mRNA expression in brain homogenates and immunohistochemistry was applied for the detection of SP-A protein expression in brain coronal slices. RESULTS: SP-A mRNA and histological evidence of protein expression were detected in both the lungs and brains of WT mice, with significantly higher amounts in lung samples. SP-A-/- mice exhibited significantly higher baseline concentrations of brain TNF-α, IL-6, and IL-1ß compared to WT mice. Oropharyngeal application of either LPS or P. aeruginosa elicited significantly higher brain levels of TNF-α and IL-1ß in SP-A-/- mice compared to WT mice at all time points. In comparison, behavioral impairment as a measure of sickness behavior, was significantly stronger in WT than in SP-A-/- mice, particularly after LPS application. CONCLUSION: SP-A is known for its anti-inflammatory role in the pulmonary immune response to bacterial infection. Recent evidence suggests that in an abdominal sepsis model SP-A deficiency can lead to increased cytokine levels in the brain. Our results extend this perception and provide evidence for an anti-inflammatory role of SP-A in the brain of adult WT mice after pulmonary infection.

Diagnosis and treatment of a patient with pulmonary infection caused by Emergomyces Orientalis: a case report.

Emergomycosis is a dimorphic fungal disease that is typically disseminated and fatal among immunocompromised individuals. In the case report, we presented a patient with intermittent fever, night sweats, coughing and phlegm. Chest computed tomography revealed multiple soft-tissue nodules in both lungs. Routine pathological and microbiological tests did not confirm the diagnosis. Therefore, we conducted pathogen detection using metagenomic next-generation sequencing in bronchoalveolar lavage fluid and identified the pulmonary infection caused by Emergomyces orientalis (Es. orientalis). During the antifungal treatment, the patient experienced renal function damage, and we have attempted various antifungal drugs for treatment. Finally, the patient's condition was brought under control. Therefore, the metagenomic next-generation sequencing pathogen detection was essential.

We report a case of a rare illness caused by the fungus Emergomyces orientalis (Es. orientalis). The patient had a fever, cough and small lumps were found in his lungs. We diagnosed the illness using a method called metagenomic next-generation sequencing that identified the fungus from the DNA in a patient sample. The drug that was given to the patient worked, but it did cause some issues with his kidneys. This report can help to inform how patients are treated in the future.

Exploring the Application of Metagenomic Next-Generation Sequencing in the Diagnosis of Unexplained Pulmonary Infection.

Background: Pulmonary infections are significant global health burdens, and conventional diagnostic methods (culture and polymerase chain reaction), are often limited by slow results and low sensitivity. Metagenomic next-generation sequencing (mNGS) offers a rapid, comprehensive alternative for identifying diverse pathogens, including rare and mixed infections. Thus, we assessed the diagnostic performance of mNGS in pulmonary infections, compared the findings with those of traditional pathogen detection methods, and explored its potential to enhance clinical diagnostics and patient care. Methods: We collected samples from 125 immunocompromised patients diagnosed with pulmonary infection at the Department of Respiratory Medicine of Shenzhen Longgang Central Hospital from March 2020 to July 2022. We compared the rate of pathogen positivity and pathogen distribution between conventional pathogen detection methods and mNGS using samples including sputum, blood, and bronchoalveolar lavage fluid. Results: Among the 125 cases of unexplained pulmonary infection, 82 (65.6%) and 40 (32.0%) tested positive for pathogens using mNGS and routine culture, respectively (P < 0.05). Both methods of pathogen detection were positive in 28 (22.4%) cases (complete match, 9; complete mismatch, 13; partial match, 6). However, 43.2% of cases only tested positive using mNGS, 9.4% only tested positive using routine tests, and 24.8% tested negative using both methods. A viral infection was present in 55.2% of cases. The detection rate of mycobacteria using mNGS (12.8%) was higher than that using conventional pathogen detection methods (5.6%). Conclusion: mNGS technology enhances pathogen detection in unexplained pulmonary infections, enabling targeted antimicrobial therapy and consequently helping to reduce broad-spectrum antibiotic use, aligning treatments more closely with the causative pathogens. Thus, mNGS offers significant clinical value by improving treatment efficacy and potentially reducing antibiotic resistance in pulmonary infection cases.

Predictive risk factors for one-year mortality in idiopathic inflammatory myopathy patients with interstitial lung disease: A retrospective, single-center cohort study.

Objectives: This study aimed to analyze the risk factors for mortality of idiopathic inflammatory myopathy (IIM) patients admitted with interstitial lung disease (ILD) to guide rapid and accurate judgment of clinical prognosis. Patients and methods: This retrospective, single-center cohort study was conducted with 135 participants (37 males, 98 females; mean age: 54.8±11.1 years; range, 24 to 85 years) between June 1, 2016, and June 30, 2021. The participants were categorized into the survival group (n=111) and nonsurvivors (n=24) according to whether they survived during the one-year follow-up. The independent risk factors for mortality in one year after discharge were analyzed. Receiver operating characteristic curve analysis was used to determine the accuracy of oxygenation index at baseline combined with pulmonary infection (PI) at follow-up to indicate death in IIM-ILD patients. Results: Compared to the survival group, nonsurvivors were older (p=0.006) and had a higher proportion of anti-MDA5 (melanoma differentiation-associated protein 5) positivity (p<0.001). The ILD duration was shorter (p=0.006), the oxygenation index was lower (p<0.001), and the intensive care unit occupancy rate (p<0.001) and ventilator utilization rate (p<0.001) were elevated in nonsurvivors compared to the survival group. Oxygenation index at baseline (odds ratio [OR]=1.021, 95% confidence interval [CI]: 1.001-1.023, p=0.040) and PI (clinical judgment) at follow-up (OR=16.471, 95% CI: 1.565-173.365, p=0.020) were found as independent risk factors for death in the year after discharge in IIM inpatients with ILD. An oxygenation index ≤279 mmHg at baseline combined with PI at follow-up exhibited a promising predictive value for all-cause death in IIM-ILD patients within one year. Conclusion: Oxygenation index at baseline and PI during follow-up were independent risk factors for death of IIM-ILD patients within one year after discharge. Patients with an oxygenation index ≤279 mmHg at baseline had an increased risk of death once they developed PI during the one-year follow-up.

Metagenomic next generation sequencing of bronchoalveolar lavage fluids for the identification of pathogens in patients with pulmonary infection: A retrospective study.

Due to the limitations of traditional laboratory methods (TMs), identification of causative pathogens of numerous pulmonary infections (PIs) remains difficult. This study evaluated the value of metagenomic next generation sequencing (mNGS) in the identification of various respiratory pathogens. A total of 207 patients with TMs and mNGS data were collected for this retrospective study. TMs included sputum culture, blood, and bronchoalveolar lavage fluid (BALF) analysis, or polymerase chain reaction analysis of throat swabs. Otherwise, BALF was collected and analyzed using mNGS. For bacterial pathogens, sensitivities of mNGS as compared to TMs were 76.74 % and 58.14 % (P=0.012). For fungal pathogens, the detection rate of mNGS sensitivity was higher as compared to that of TMs (93.68 % vs 22.11 %; P<0.001). The positive predictive value and negative predictive value were also greater for mNGS. Use of mNGS for BALF analysis offers good specificity and thus facilitates to the clinical diagnosis of PIs.

Gut microbes improve prognosis of Klebsiella pneumoniae pulmonary infection through the lung-gut axis.

Background: The gut microbiota plays a vital role in the development of sepsis and in protecting against pneumonia. Previous studies have demonstrated the existence of the gut-lung axis and the interaction between the gut and the lung, which is related to the prognosis of critically ill patients; however, most of these studies focused on chronic lung diseases and influenza virus infections. The purpose of this study was to investigate the effect of faecal microbiota transplantation (FMT) on Klebsiella pneumoniae-related pulmonary infection via the gut-lung axis and to compare the effects of FMT with those of traditional antibiotics to identify new therapeutic strategies. Methods: We divided the mice into six groups: the blank control (PBS), pneumonia-derived sepsis (KP), pneumonia-derived sepsis + antibiotic (KP + PIP), pneumonia-derived sepsis + faecal microbiota transplantation(KP + FMT), antibiotic treatment control (KP+PIP+PBS), and pneumonia-derived sepsis+ antibiotic + faecal microbiota transplantation (KP + PIP + FMT) groups to compare the survival of mice, lung injury, inflammation response, airway barrier function and the intestinal flora, metabolites and drug resistance genes in each group. Results: Alterations in specific intestinal flora can occur in the gut of patients with pneumonia-derived sepsis caused by Klebsiella pneumoniae. Compared with those in the faecal microbiota transplantation group, the antibiotic treatment group had lower levels of proinflammatory factors and higher levels of anti-inflammatory factors but less amelioration of lung pathology and improvement of airway epithelial barrier function. Additionally, the increase in opportunistic pathogens and drug resistance-related genes in the gut of mice was accompanied by decreased production of favourable fatty acids such as acetic acid, propionic acid, butyric acid, decanoic acid, and secondary bile acids such as chenodeoxycholic acid 3-sulfate, isodeoxycholic acid, taurodeoxycholic acid, and 3-dehydrocholic acid; the levels of these metabolites were restored by faecal microbiota transplantation. Faecal microbiota transplantation after antibiotic treatment can gradually ameliorate gut microbiota disorder caused by antibiotic treatment and reduce the number of drug resistance genes induced by antibiotics. Conclusion: In contrast to direct antibiotic treatment, faecal microbiota transplantation improves the prognosis of mice with pneumonia-derived sepsis caused by Klebsiella pneumoniae by improving the structure of the intestinal flora and increasing the level of beneficial metabolites, fatty acids and secondary bile acids, thereby reducing systemic inflammation, repairing the barrier function of alveolar epithelial cells, and alleviating pathological damage to the lungs. The combination of antibiotics with faecal microbiota transplantation significantly alleviates intestinal microbiota disorder, reduces the selection for drug resistance genes caused by antibiotics, and mitigates lung lesions; these effects are superior to those following antibiotic monotherapy.

[Analysis of Risk Factors for Pulmonary Infection in Patients with Acute Leukemia after Chemotherapy].

OBJECTIVE: To investigate the risk factors of pulmonary infection in patients with acute leukemia (AL) after chemotherapy. METHODS: A total of 294 patients with AL were collected and divided into infection group (n=93) and control group (n=201) according to whether the pulmonary infection occurred after chemotherapy. Analyze the correlation between sociodemographic data (sex, age, BMI), clinical data (disease type, ECOG score, invasive procedure, underlying disease, hormone therapy, empirical use of antibiotics, prognosis stratification, chemotherapy intensity, primitive cell count, white blood cell count, neutrophil count, duration of granulocyte deficiency, platelet count, hemoglobin, and albumin and pulmonary infection after chemotherapy. COX regression method was used to analyze the risk factors of pulmonary infection in AL patients after chemotherapy. RESULTS: Among 294 patients with AL, 11 died within 30 days after pulmonary infection. There were statistically significant differences in age, smoking history, ECOG score, invasive procedure, hormone therapy, empirical use of antibiotics, prognosis stratification, chemotherapy intensity, primitive cell count, neutrophil count, duration of granulocyte deficiency, platelet count, hemoglobin, albumin and fasting blood glucose between the 2 groups (P <0.05). COX regression analysis showed that smoking history, invasive procedure, unexperienced use of antibiotics, poor prognosis, long duration of granulocytopenia, low platelet level and low albumin were high risk factors for pulmonary infection in AL patients after chemotherapy (P <0.05). CONCLUSION: Smoking, invasive procedures, unexperienced use of antibiotics, poor prognosis, long duration of granulodeficiency, low platelet levels and low albumin are risk factors for pulmonary infection in AL patients after chemotherapy.

Serum Albumin-to-Creatinine Ratio: A Novel Predictor of Pulmonary Infection in Patients with ST-Segment Elevation Myocardial Infarction Undergoing Percutaneous Coronary Intervention.

AIM: In patients with ST-segment elevation myocardial infarction (STEMI) undergoing percutaneous coronary intervention (PCI), a low serum albumin-to-creatinine ratio (sACR) is associated with elevated risk of poor short- and long-term outcomes. However, the relationship between sACR and pulmonary infection during hospitalization in patients with STEMI undergoing PCI remains unclear. METHODS: A total of 4,507 patients with STEMI undergoing PCI were enrolled and divided into three groups according to sACR tertile. The primary outcome was pulmonary infection during hospitalization, and the secondary outcome was in-hospital major adverse cardiovascular events (MACE) including stroke, in-hospital mortality, target vessel revascularization, recurrent myocardial infarction, and all-cause mortality during follow-up. RESULTS: Overall, 522 (11.6%) patients developed pulmonary infections, and 223 (4.9%) patients developed in-hospital MACE. Cubic spline models indicated a non-linear, L-shaped relationship between sACR and pulmonary infection (P=0.039). Receiver operating characteristic curve analysis indicated that sACR had good predictive value for both pulmonary infection (area under the ROC curve [AUC]=0.73, 95% CI=0.70-0.75, P＜0.001) and in-hospital MACE (AUC=0.72, 95% CI=0.69-0.76, P＜0.001). Kaplan-Meier survival analysis indicated that higher sACR tertiles were associated with a greater cumulative survival rate (P＜0.001). Cox regression analysis identified lower sACR as an independent predictor of long-term all-cause mortality (hazard ratio [HR]=0.96, 95% CI=0.95-0.98, P＜0.001). CONCLUSIONS: A low sACR was significantly associated with elevated risk of pulmonary infection and MACE during hospitalization, as well as all-cause mortality during follow-up among patients with STEMI undergoing PCI. These findings highlighted sACR as an important prognostic marker in this patient population.

Pulmonary infection with Aeromonas dhakensis in a patient with acute T lymphoblastic leukemia: a case report and review of the literature.

Background: Aeromonas dhakensis is a gram-negative bacterium. In recent years, Aeromonas dhakensis has gradually attracted increasing attention due to its strong virulence and poor prognosis. Clinical reports of pulmonary infection caused by Aeromonas dhakensis are rare. Case presentation: A patient with acute T lymphoblastic leukemia experienced myelosuppression after chemotherapy, developed a secondary pulmonary infection with Aeromonas dhakensis and was hospitalized due to fever. The patient underwent testing for inflammatory markers, chest imaging, blood culture, bronchoalveolar lavage, pleural drainage, and metagenomic next-generation sequencing of alveolar lavage fluid and pleural fluid to obtain evidence of Aeromonas dhakensis infection, and was treated with four generations of cephalosporin combined with fluoroquinolone antibiotics. The patient's condition significantly improved. Discussion: Among pulmonary infectious pathogens, Aeromonas dhakensis is relatively rare. Once an Aeromonas strain is cultured in the clinical work, pathogenic sequencing should be performed on the detected samples for early accurate diagnosis and effective anti-infection treatment.