miR-486-5p predicted adverse outcomes of SCAP and regulated K. pneumonia infection via FOXO1.

PURPOSE: Severe community-acquired pneumonia (SCAP) is a common respiratory system disease with rapid development and high mortality. Exploring effective biomarkers for early detection and development prediction of SCAP is of urgent need. The function of miR-486-5p in SCAP diagnosis and prognosis was evaluated to identify a promising biomarker for SCAP. PATIENTS AND METHODS: The serum miR-486-5p in 83 patients with SCAP, 52 healthy individuals, and 68 patients with mild CAP (MCAP) patients were analyzed by PCR. ROC analysis estimated miR-486-5p in screening SCAP, and the Kaplan-Meier and Cox regression analyses evaluated the predictive value of miR-486-5p. The risk factors for MCAP patients developing SCAP were assessed by logistic analysis. The alveolar epithelial cell was treated with Klebsiella pneumonia to mimic the occurrence of SCAP. The targeting mechanism underlying miR-486-5p was evaluated by luciferase reporter assay. RESULTS: Upregulated serum miR-486-5p screened SCAP from healthy individuals and MCAP patients with high sensitivity and specificity. Increasing serum miR-486-5p predicted the poor outcomes of SCAP and served as a risk factor for MCAP developing into SCAP. K. pneumonia induced suppressed proliferation, significant inflammation and oxidative stress in alveolar epithelial cells, and silencing miR-486-5p attenuated it. miR-486-5p negatively regulated FOXO1, and the knockdown of FOXO1 reversed the effect of miR-486-5p in K. pneumonia-treated alveolar epithelial cells. CONCLUSION: miR-486-5p acted as a biomarker for the screening and monitoring of SCAP and predicting the malignancy of MCAP. Silencing miR-486-5p alleviated inflammation and oxidative stress induced by K. pneumonia via negatively modulating FOXO1.

Mycobacterium avium and Klebsiella pneumoniae co-infection in the domestic ferret (Mustela putorius furo) - Case Report.

Introduction and Objective. Pets infected with zoonotic pathogens might become a source of infections for their owners, especially those who are immuno-compromised. The aim of this report is to describe a case of chronic, untreatable pneumonia in a domestic ferret. Materials and method. The subject was a 5-year-old female ferret suffering from recurrent pneumonia. Ante-mortally, swabs from the nasal cavity, alveolus and throat were collected from the animal. Post-mortally, lesioned organ fragments were collected. Standard microbiological testing was performed. Additionally, mycobacterial diagnosis including culture and molecular tests was performed. Results. The co-infection of Mycobacterium avium and Klebsiella pneumoniae was microbiologically confirmed. Conclusions. This case demonstrates the need to pay attention to the possibility of zoonotic pathogens in ferrets. Veterinarians diagnosing ferrets are potentially exposed to Mycobacteria spp. infections and other pathogens.

Detection of hidden antibiotic resistance through real-time genomics.

Real-time genomics through nanopore sequencing holds the promise of fast antibiotic resistance prediction directly in the clinical setting. However, concerns about the accuracy of genomics-based resistance predictions persist, particularly when compared to traditional, clinically established diagnostic methods. Here, we leverage the case of a multi-drug resistant Klebsiella pneumoniae infection to demonstrate how real-time genomics can enhance the accuracy of antibiotic resistance profiling in complex infection scenarios. Our results show that unlike established diagnostics, nanopore sequencing data analysis can accurately detect low-abundance plasmid-mediated resistance, which often remains undetected by conventional methods. This capability has direct implications for clinical practice, where such "hidden" resistance profiles can critically influence treatment decisions. Consequently, the rapid, in situ application of real-time genomics holds significant promise for improving clinical decision-making and patient outcomes.

Identification of hypermucoviscous Klebsiella pneumoniae K1, K2, K54 and K57 capsular serotypes by Raman spectroscopy.

Antimicrobial resistance poses a significant challenge in modern medicine, affecting public health. Klebsiella pneumoniae infections compound this issue due to their broad range of infections and the emergence of multiple antibiotic resistance mechanisms. Efficient detection of its capsular serotypes is crucial for immediate patient treatment, epidemiological tracking and outbreak containment. Current methods have limitations that can delay interventions and increase the risk of morbidity and mortality. Raman spectroscopy is a promising alternative to identify capsular serotypes in hypermucoviscous K. pneumoniae isolates. It provides rapid and in situ measurements with minimal sample preparation. Moreover, its combination with machine learning tools demonstrates high accuracy and reproducibility. This study analyzed the viability of combining Raman spectroscopy with one-dimensional convolutional neural networks (1-D CNN) to classify four capsular serotypes of hypermucoviscous K. pneumoniae: K1, K2, K54 and K57. Our approach involved identifying the most relevant Raman features for classification to prevent overfitting in the training models. Simplifying the dataset to essential information maintains accuracy and reduces computational costs and training time. Capsular serotypes were classified with 96 % accuracy using less than 30 Raman features out of 2400 contained in each spectrum. To validate our methodology, we expanded the dataset to include both hypermucoviscous and non-mucoid isolates and distinguished between them. This resulted in an accuracy rate of 94 %. The results obtained have significant potential for practical healthcare applications, especially for enabling the prompt prescription of the appropriate antibiotic treatment against infections.

Rapid, culture-free detection of carbapenem-resistant Klebsiella pneumoniae in a case of bloodstream infection using genomics.

Timely diagnosis and treatment of sepsis is a major challenge faced by critical care specialists around the world. The traditional blood culture methods have a significant turnaround time which delays targeted therapy leading to poor prognosis. In the current study, we highlight the clinical utility of a genomics solution for diagnosis and management of bloodstream infections by combining the real-time DNA sequencing of Oxford Nanopore Technology with an automated genomic data analysis software. We identify a carbapenem-resistant Klebsiella pneumoniae directly from a blood sample in <24 hours and thereby prove the effectiveness of the test in early diagnosis of sepsis.

Performance comparison of BD Phoenix CPO detect panel with Cepheid Xpert Carba-R assay for the detection of carbapenemase-producing Klebsiella pneumoniae isolates.

BACKGROUND: We aimed to compare the performance of carbapenemase classification in carbapenem-resistant Klebsiella pneumoniae (CRKP) obtained using the BD Phoenix CPO Detect panel (CPO panel) and Cepheid Xpert Carba-R assays. We analyzed 55 CRKP strains from clinical specimens collected between November 2020 and November 2022. The CPO panel was used to detect both antibiotic susceptibility and phenotypic carbapenemase classes, while Xpert Carba-R was employed to identify KPC, NDM, VIM, OXA-48, and IMP genes. Due to the limited availability of molecular kits, we arbitrarily selected 55 isolates, identified as carbapenemase-producing according to the CPO panel and with meropenem minimum inhibitory concentration values > 8 mg/L. RESULTS: According to the Xpert Carba-R assay, 16 of the 55 isolates (29.1%) were categorised as Ambler Class A (11 of which matched CPO panel Class A identification); three isolates (5.5%) were identified as Class B and 27 isolates (49.1%) as Class D (in both cases consistent with CPO panel B and D classifications). A further eight isolates (14.5%) exhibited multiple carbapenemase enzymes and were designated as dual-carbapenemase producers, while one isolate (1.8%) was identified as a non-carbapenemase-producer. The CPO panel demonstrated positive and negative percent agreements of 100% and 85.7% for Ambler Class A, 100% and 100% for Class B, and 96.4% and 100% for Class D carbapenemase detection, respectively. CONCLUSION: While the CPO panel's phenotypic performance was satisfactory in detecting Class B and D carbapenemases, additional confirmatory testing may be necessary for Class A carbapenemases as part of routine laboratory procedures.

A Multiplex Recombinase-Aided qPCR Assay for Highly Sensitive and Rapid Detection of khe, blaKPC -2, and blaNDM -1 Genes in Klebsiella pneumoniae.

OBJECTIVE: This study aimed to establish a highly sensitive and rapid single-tube, two-stage, multiplex recombinase-aided qPCR (mRAP) assay to specifically detect the khe, blaKPC-2, and blaNDM-1 genes in Klebsiella pneumoniae. METHODS: mRAP was carried out in a qPCR instrument within 1 h. The analytical sensitivities of mRAP for khe, blaKPC-2, and blaNDM-1 genes were tested using recombinant plasmids and dilutions of reference strains. A total of 137 clinical isolates and 86 sputum samples were used to validate the clinical performance of mRAP. RESULTS: mRAP achieved the sensitivities of 10, 8, and 14 copies/reaction for khe, blaKPC-2, and blaNDM-1 genes, respectively, superior to qPCR. The Kappa value of qPCR and mRAP for detecting khe, blaKPC-2, and blaNDM-1 genes was 1, 0.855, and 1, respectively (p < 0.05). CONCLUSION: mRAP is a rapid and highly sensitive assay for potential clinical identification of khe, blaKPC-2, and blaNDM-1 genes in K. pneumoniae.

A case report on rapid development of simultaneous liver and musculature calcifications in severe sepsis.

A 76-year-old Malay female presented with 2 days history of fever and vomiting. She was found to have Escherichia coli and Klebsiella pneumoniae bacteraemia with no clear intra-abdominal cause on the initial computed tomography of the abdomen and pelvis (CTAP). She clinically improved with 2 weeks duration of intravenous meropenem. She subsequently developed septic shock and a repeated CTAP demonstrated increased hepatic parenchymal density with extensive parenchymal calcifications. Curvilinear calcifications were seen in the paraspinal and pelvic musculature.

OriPlex: Origami-enabled multiplexed detection of respiratory pathogens.

Origami biosensors leverage paper foldability to develop total analysis systems integrated in a single piece of paper. This capability can also be utilized to incorporate additional features that would be difficult to achieve with rigid substrates. In this article, we report a new design for 3D origami biosensors called OriPlex, which leverages the foldability of filter paper for the multiplexed detection of bacterial pathogens. OriPlex immunosensors detect pathogens by folding nanoparticle reservoirs containing different types of nanoprobes. This releases antibody-coated nanoparticles in a central channel where targets are captured through physical interactions. The OriPlex concept was demonstrated by detecting the respiratory pathogens Pseudomonas aeruginosa (PA) and Klebsiella pneumoniae (KP) with a limit of detection of 3.4·103 cfu mL-1 and 1.4·102 cfu mL-1, respectively, and with a turn-around time of 25 min. Remarkably, the OriPlex biosensors allowed the multiplexed detection of both pathogens spiked into real bronchial aspirate (BAS) samples at a concentration of 105 cfu mL-1 (clinical infection threshold), thus demonstrating their suitability for diagnosing lower tract respiratory infections. The results shown here pave the way for implementing OriPlex biosensors as a screening test for detecting superbugs requiring personalized antibiotics in suspected cases of nosocomial pneumonia.

[A case of liver abscess with meningitis and endophthalmitis: invasive liver abscess syndrome].

A woman in her 70s was hospitalized and was diagnosed with liver abscess and managed with antibiotics in a previous hospital. However, she experienced altered consciousness and neck stiffness during treatment. She was then referred to our hospital. On investigation, we found that she had meningitis and right endophthalmitis concurrent with a liver abscess. Klebsiella pneumoniae was detected from both cultures of the liver abscess and effusion from the cornea. A string test showed a positive result. Therefore, she was diagnosed with invasive liver abscess syndrome. Although she recovered from the liver abscess and meningitis through empiric antibiotic treatment, her right eye required ophthalmectomy. In cases where a liver abscess presents with extrahepatic complications, such as meningitis and endophthalmitis, the possibility of invasive liver abscess syndrome should be considered, which is caused by a hypervirulent K. pneumoniae.

Infrared spectroscopy-based machine learning algorithms for rapid detection of Klebsiella pneumoniae isolated directly from patients' urine and determining its susceptibility to antibiotics.

Among the most prevalent and detrimental bacteria causing urinary tract infections (UTIs) is Klebsiella (K.) pneumoniae. A rapid determination of its antibiotic susceptibility can enhance patient treatment and mitigate the spread of resistant strains. In this study, we assessed the viability of using infrared spectroscopy-based machine learning as a rapid and precise approach for detecting K. pneumoniae bacteria and determining its susceptibility to various antibiotics directly from a patient's urine sample. In this study, 2333 bacterial samples, including 636 K. pneumoniae were investigated using infrared micro-spectroscopy. The obtained spectra (27996spectra) were analyzed with XGBoost classifier, achieving a success rate exceeding 95 % for identifying K. pneumoniae. Moreover, this method allows for the simultaneous determination of K. pneumoniae susceptibility to various antibiotics with sensitivities ranging between 74 % and 81 % within approximately 40 min after receiving the patient's urine sample.

Acute Exacerbation of Chronic Obstructive Pulmonary Disease Due to Carbapenem-Resistant Klebsiella pneumoniae-Induced Pneumonia: Clinical Features and Prognostic Factors.

Purpose: Carbapenem-resistant Klebsiella pneumoniae (CRKP) is closely related to respiratory tract infection. The aim of this study was to investigate the clinical features and prognostic factors of CRKP-induced pneumonia in acute exacerbation of chronic obstructive pulmonary disease (AECOPD) patients. Methods: A single-centre, retrospective case-control study on COPD patients hospitalized for acute exacerbation and CRKP-induced pneumonia was conducted from January 1, 2016, to December 31, 2022. The mortality rate of acute exacerbation due to CRKP-induced pneumonia was investigated. The patients were divided into the CRKP-induced pneumonic acute exacerbation (CRKPpAE) group and the non-CRKP-induced pneumonic acute exacerbation (non-CRKPpAE) group, and the clinical characteristics and prognostic factors were compared using univariate analysis and multivariate analysis. Results: A total of 65 AECOPD patients were included, composed of 26 patients with CRKPpAE and 39 patients with non-CRKPpAE. The mortality rate of CRKPpAE was 57.69%, while non-CRKPpAE was 7.69%. Compared with non-CRKPpAE, a history of acute exacerbation in the last year (OR=8.860, 95% CI: 1.360-57.722, p=0.023), ICU admission (OR=11.736, 95% CI: 2.112-65.207, p=0.005), higher NLR levels (OR=1.187, 95% CI: 1.037-1.359, p=0.013) and higher D-dimer levels (OR=1.385, 95% CI: 1.006-1.905, p=0.046) were independently related with CRKPpAE. CRKP isolates were all MDR strains (26/26, 100%), and MDR strains were also observed in non-CRKP isolates (5/39, 12.82%). Conclusion: Compared with non-CRKPpAE, CRKPpAE affects the COPD patient's condition more seriously and significantly increases the risk of death.

Time to positivity of Klebsiella pneumoniae in blood cultures as prognostic marker in patients with intra-abdominal infection: A retrospective study.

Klebsiella pneumoniae is a common causative pathogen of intra-abdominal infection with concomitant bacteraemia, leading to a significant mortality risk. The time to positivity (TTP) of blood culture is postulated to be a prognostic factor in bacteraemia caused by other species. Therefore, this study aimed to investigate the prognostic value of TTP in these patients. The single-centred, retrospective, observational cohort study was conducted between 1 July 2016 and 30 June 2021. All adult emergency department patients with diagnosis of intra-abdominal infection and underwent blood culture collection which yield K. pneumoniae during this period were enrolled. A total of 196 patients were included in the study. The overall 30-day mortality rate was 12.2% (24/196), and the median TTP of the studied cohort was 12.3 h (10.5-15.8 h). TTP revealed a moderate 30-day mortality discriminative ability (area under the curve 0.73, p < 0.001). Compared with the late TTP group (>12 h, N = 109), patients in the early TTP (≤12 h, N = 87) group had a significantly higher risk of 30-day morality (21.8% vs. 4.6%, p < 0.01) and other adverse outcomes. Furthermore, TTP (odds ratio [OR] = 0.79, p = 0.02), Pitt bacteraemia score (OR = 1.30, p = 0.03), and implementation of source control (OR = 0.06, p < 0.01) were identified as independent factors related to 30-day mortality risk in patients with intra-abdominal infection and K. pneumoniae bacteraemia. Therefore, physicians can use TTP for prognosis stratification in these patients.

Patient Characteristics Associated with Concurrent Klebsiella pneumoniae Infection and Severe Pulmonary Tuberculosis.

BACKGROUND: This study aims to investigate the clinical characteristics associated with concurrent Klebsiella pneu-moniae (K. pneumoniae) infection in hospitalized patients with severe pulmonary tuberculosis. METHODS: A retrospective study was conducted on hospitalized severe pulmonary tuberculosis patients between January 2019 and December 2020. Among the 487 patients with severe pulmonary tuberculosis, a positive sputum culture for K. pneumoniae was reported in 76 patients (15.6%, 61 males and 15 females). RESULTS: Among these patients, 27 (35.5%) and 49 (64.5%) patients were with and without K. pneumoniae infection, respectively. Compared to patients without K. pneumoniae infection, patients with K. pneumoniae infection had higher mortality (16.3% vs. 40.7%, p = 0.02), and lower inhibitory/cytotoxic CD8 count (24.2 ± 9.9 vs. 17.8 ± 8.0, p = 0.02), complement C4 (0.3 ± 0.1 vs. 0.2 ± 0.1, p = 0.01), and retinol-binding protein level (32.2 ± 22.2 vs. 22.4 ± 11.8, p = 0.02). Furthermore, the acute Physiology and Chronic Health Evaluation II score was associated with the K. pneumoniae infection in severe pulmonary tuberculosis patients. CONCLUSIONS: It can be concluded that a significant number of severe pulmonary tuberculosis patients can have concurrent K. pneumoniae infection. Immunity, nutritional status, and disease severity are associated with the concurrent infection of K. pneumoniae in these patients.

Emphysematous pyometra and emphysematous hepatitis caused by Klebsiella pneumoniae infection in a diabetic dog.

A 14-year-old intact female diabetic dog presented with seizures and hyperglycemic hyperosmolar syndrome. Radiographs revealed gas-filled tubular structures in the right and left caudal abdomen, raising concerns of emphysematous pyometra or small intestinal ileus. Ultrasonography played a pivotal role in confirming emphysematous pyometra, a technique previously documented only once in veterinary practice. This report also presents the first documented case of emphysematous pyometra in a diabetic dog attributed to Klebsiella pneumoniae and complicated by emphysematous hepatitis.

Case report: A case of high virulence and multidrug resistant Klebsiella pneumoniae liver abscess in Ningxia, China.

RATIONALE: Highly virulent multidrug-resistant Klebsiella pneumoniae (KP) is becoming more and more common in clinical practice, especially the rise of carbapenem-resistant KP in clinical practice, resulting in the emergence of KP liver abscess in Ningxia, China. For the prognosis of liver abscess patients, it is particularly important to identify the types of pathogens and identify antibiotics that are sensitive to the pathogens. PATIENT CONCERNS: A 73-year-old man from China presents to our hospital with abdominal pain, jaundice and fever. Patients have no obvious cause of abdominal pain, abdominal distension, and abdominal pain is persistent. Abdominal examination showed hepatomegaly, no tenderness 2 cm from the right costal margin, abdominal distension and other general examinations did not have obvious abnormalities. He had no history of hypertension and diabetes, ERCP was performed for cholangiocarcinoma 1 year before the current visit, and no significant complications occurred. DIAGNOSES: His initial diagnosis was obstructive cholangitis, and computed tomographic images and liver drainage fluid bacterial culture and genetic polymerase chain reaction tests later determined that the patient had KP liver abscess. INTERVENTIONS: Drainage by liver catheter and antibiotic treatment for 7 weeks. OUTCOMES: The patient liver abscess is basically gone. LESSION: It is particularly important to optimize the diagnosis of liver abscess pathogens for timely and effective treatment of patients.