1
|
Ai G, Zhang Y, Guo K, Zhao L, Li Z, Hai H, Jia E, Liu J. The impact of optimizing microbial diagnosis processes on clinical and healthcare economic outcomes in hospitalized patients with bloodstream infections. Eur J Clin Microbiol Infect Dis 2024:10.1007/s10096-024-04928-2. [PMID: 39240272 DOI: 10.1007/s10096-024-04928-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2024] [Accepted: 08/23/2024] [Indexed: 09/07/2024]
Abstract
PURPOSE Bloodstream infections (BSIs) are associated with significant morbidity, mortality and costs, while prolonged blood culture (BC) diagnosis may delay the initiation of targeted therapy. This study evaluates the impact of an optimized microbiology laboratory process on turnaround times, antibiotic use, clinical outcomes and economics for hospitalized BSI patients. METHODS A pre-post study was conducted in a Chinese hospital in which BSI derived BC results before (Oct. 2020- Sep. 2021) and after (Oct. 2021- Sep. 2022) newly implemented microbiology diagnostics and workflow changes were analyzed. Turnaround times, antibiotic initiation, length of stay and in-hospital costs were compared. RESULTS From 213 included patients, 134 were pre-optimization (pre-op) and 79 were post-optimization (post-op) cases. The median time from blood sample collection (BSC) to pathogen identification (ID) decreased from 70.12 to 47.43 h post-op (P < 0.001). The median time from BSC to the first ID report related initiation of pathogen-directed antibiotic use decreased from 88.48 to 47.85 h post-op (P < 0.001). The average hospital stay decreased from 19.54 to 16.79 days and 30-day readmissions declined from 18.7 to 13.9%, while the mean total antimicrobial drug usage costs decreased by 3,889 CNY per patient (P = 0.022) after optimization. CONCLUSIONS Implementing new diagnostics technologies and optimizing laboratory workflows significantly reduced antimicrobial drug usage costs, shortened the time to ID results and improved the timeliness of appropriate antibiotic choices to treat BSIs. Investments in faster testing and process improvements were clearly beneficial for patient outcomes and healthcare economics.
Collapse
Affiliation(s)
- Genwei Ai
- Department of Laboratory Medicine, Xuchang Central Hospital, No. 666 Wenxuan Street, Xuchang, 461000, China.
| | - Ying Zhang
- Department of Laboratory Medicine, Xuchang Central Hospital, No. 666 Wenxuan Street, Xuchang, 461000, China
| | - Kunshan Guo
- Department of Laboratory Medicine, Xuchang Central Hospital, No. 666 Wenxuan Street, Xuchang, 461000, China
| | - Lu Zhao
- Department of Laboratory Medicine, Xuchang Central Hospital, No. 666 Wenxuan Street, Xuchang, 461000, China
| | - Zhi Li
- Department of Laboratory Medicine, Xuchang Central Hospital, No. 666 Wenxuan Street, Xuchang, 461000, China
| | - He Hai
- Department of Laboratory Medicine, Xuchang Central Hospital, No. 666 Wenxuan Street, Xuchang, 461000, China
| | - Erjuan Jia
- Department of Laboratory Medicine, Xuchang Central Hospital, No. 666 Wenxuan Street, Xuchang, 461000, China
| | - Junying Liu
- Department of Laboratory Medicine, Xuchang Central Hospital, No. 666 Wenxuan Street, Xuchang, 461000, China
| |
Collapse
|
2
|
Li Z, Zhang F, Sun M, Liu J, Zhao L, Liu S, Li S, Wang B. The modulatory effects of gut microbes and metabolites on blood–brain barrier integrity and brain function in sepsis-associated encephalopathy. PeerJ 2023; 11:e15122. [PMID: 37009158 PMCID: PMC10064995 DOI: 10.7717/peerj.15122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Accepted: 03/03/2023] [Indexed: 03/30/2023] Open
Abstract
Background
Intestinal microbiota homeostasis and the gut-brain axis are key players associated with host health and alterations in metabolic, inflammatory, and neurodegenerative disorders. Sepsis-associated encephalopathy (SAE), which is closely associated with bacterial translocation, is a common secondary organ dysfunction and an urgent, unsolved problem affecting patient quality of life. Our study examined the neuroprotective effects of the gut microbiome and short-chain fatty acid (SCFA) metabolites on SAE.
Methods
Male C57BL/6 mice were administered SCFAs in drinking water, then subjected to cecal ligation and puncture (CLP) surgery to induce SAE. 16S rRNA sequencing was used to investigate gut microbiome changes. The open field test (OFT) and Y-maze were performed to evaluate brain function. The permeability of the blood–brain barrier (BBB) was assessed by Evans blue (EB) staining. Hematoxylin and eosin (HE) staining was used to examine intestinal tissue morphology. The expression levels of tight junction (TJ) proteins and inflammatory cytokines was assessed by western blots and immunohistochemistry. In vitro, bEND.3 cells were incubated with SCFAs and then with lipopolysaccharide (LPS). Immunofluorescence was used to examine the expression of TJ proteins.
Results
The composition of the gut microbiota was altered in SAE mice; this change may be related to SCFA metabolism. SCFA treatment significantly alleviated behavioral dysfunction and neuroinflammation in SAE mice. SCFAs upregulated occludin and ZO-1 expression in the intestine and brain in SAE mice and LPS-treated cerebromicrovascular cells.
Conclusions
These findings suggested that disturbances in the gut microbiota and SCFA metabolites play key roles in SAE. SCFA supplementation could exert neuroprotective effects against SAE by preserving BBB integrity.
Collapse
Affiliation(s)
- Zhaoying Li
- Department of Anesthesiology, Guizhou Provincial People’s Hospital, Guiyang, Guizhou Province, China
- Institute of Anesthesiology, Guizhou Medical University, Guiyang, Guizhou Province, China
| | - Fangxiang Zhang
- Department of Anesthesiology, Guizhou Provincial People’s Hospital, Guiyang, Guizhou Province, China
| | - Meisha Sun
- Department of Anesthesiology, Guizhou Provincial People’s Hospital, Guiyang, Guizhou Province, China
| | - Jia Liu
- Department of Anesthesiology, Guizhou Provincial People’s Hospital, Guiyang, Guizhou Province, China
| | - Li Zhao
- Department of Anesthesiology, Guizhou Provincial People’s Hospital, Guiyang, Guizhou Province, China
| | - Shuchun Liu
- Department of Anesthesiology, Guizhou Provincial People’s Hospital, Guiyang, Guizhou Province, China
| | - Shanshan Li
- Department of Anesthesiology, Guizhou Provincial People’s Hospital, Guiyang, Guizhou Province, China
| | - Bin Wang
- Department of Anesthesiology, Guizhou Provincial People’s Hospital, Guiyang, Guizhou Province, China
| |
Collapse
|
3
|
Zhang Y, Xie Z, Zhou J, Li Y, Ning C, Su Q, Ye L, Ai S, Lai J, Pan P, Liu N, Liao Y, Su Q, Li Z, Liang H, Cui P, Huang J. The altered metabolites contributed by dysbiosis of gut microbiota are associated with microbial translocation and immune activation during HIV infection. Front Immunol 2023; 13:1020822. [PMID: 36685491 PMCID: PMC9845923 DOI: 10.3389/fimmu.2022.1020822] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Accepted: 11/28/2022] [Indexed: 01/05/2023] Open
Abstract
Background The immune activation caused by microbial translocation has been considered to be a major driver of HIV infection progression. The dysbiosis of gut microbiota has been demonstrated in HIV infection, but the interplay between gut microbiota and its metabolites in the pathogenesis of HIV is seldom reported. Methods We conducted a case-controlled study including 41 AIDS patients, 39 pre-AIDS patients and 34 healthy controls. Both AIDS group and pre-AIDS group were divided according to clinical manifestations and CD4 + T cell count. We collected stool samples for 16S rDNA sequencing and untargeted metabolomics analysis, and examined immune activation and microbial translocation for blood samples. Results The pre-AIDS and AIDS groups had higher levels of microbial translocation and immune activation. There were significant differences in gut microbiota and metabolites at different stages of HIV infection. Higher abundances of pathogenic bacteria or opportunistic pathogen, as well as lower abundances of butyrate-producing bacteria and bacteria with anti-inflammatory potential were associated with HIV severity. The metabolism of tryptophan was disordered after HIV infection. Lower level of anti-inflammatory metabolites and phosphonoacetate, and higher level of phenylethylamine and polyamines were observed in HIV infection. And microbial metabolic pathways related to altered metabolites differed. Moreover, disrupted metabolites contributed by altered microbiota were found to be correlated to microbial translocation and immune activation. Conclusions Metabolites caused by dysbiosis of gut microbiota and related metabolic function are correlated to immune activation and microbial translocation, suggesting that the effect of microbiota on metabolites is related to intestinal barrier disruption in HIV infection.
Collapse
Affiliation(s)
- Yu Zhang
- Guangxi Key Laboratory of AIDS Prevention and Treatment and Guangxi Universities Key Laboratory of Prevention and Control of Highly Prevalent Disease, Nanning, China
- School of Public Health, Guangxi Medical University, Nanning, China
- The Tenth Affiliated Hospital of Guangxi Medical University, Qinzhou, China
| | - Zhiman Xie
- Department of Infectious Diseases, The Fourth People's Hospital of Nanning, Nanning, China
| | - Jie Zhou
- Guangxi Key Laboratory of AIDS Prevention and Treatment and Guangxi Universities Key Laboratory of Prevention and Control of Highly Prevalent Disease, Nanning, China
- School of Public Health, Guangxi Medical University, Nanning, China
| | - Yanjun Li
- Department of Infectious Diseases, The Fourth People's Hospital of Nanning, Nanning, China
| | - Chuanyi Ning
- Guangxi Key Laboratory of AIDS Prevention and Treatment and Guangxi Universities Key Laboratory of Prevention and Control of Highly Prevalent Disease, Nanning, China
| | - Qisi Su
- Department of Infectious Diseases, The Fourth People's Hospital of Nanning, Nanning, China
| | - Li Ye
- Guangxi Key Laboratory of AIDS Prevention and Treatment and Guangxi Universities Key Laboratory of Prevention and Control of Highly Prevalent Disease, Nanning, China
- School of Public Health, Guangxi Medical University, Nanning, China
| | - Sufang Ai
- Department of Infectious Diseases, The Fourth People's Hospital of Nanning, Nanning, China
| | - Jingzhen Lai
- Guangxi Key Laboratory of AIDS Prevention and Treatment and Guangxi Universities Key Laboratory of Prevention and Control of Highly Prevalent Disease, Nanning, China
- Life Science Institute, Guangxi Medical University, Nanning, China
| | - Peijiang Pan
- Guangxi Key Laboratory of AIDS Prevention and Treatment and Guangxi Universities Key Laboratory of Prevention and Control of Highly Prevalent Disease, Nanning, China
- Life Science Institute, Guangxi Medical University, Nanning, China
| | - Ningmei Liu
- Department of Infectious Diseases, The Fourth People's Hospital of Nanning, Nanning, China
| | - Yanyan Liao
- Guangxi Key Laboratory of AIDS Prevention and Treatment and Guangxi Universities Key Laboratory of Prevention and Control of Highly Prevalent Disease, Nanning, China
- Life Science Institute, Guangxi Medical University, Nanning, China
| | - Qijian Su
- The Tenth Affiliated Hospital of Guangxi Medical University, Qinzhou, China
| | - Zhuoxin Li
- Guangxi Key Laboratory of AIDS Prevention and Treatment and Guangxi Universities Key Laboratory of Prevention and Control of Highly Prevalent Disease, Nanning, China
- School of Public Health, Guangxi Medical University, Nanning, China
| | - Hao Liang
- Guangxi Key Laboratory of AIDS Prevention and Treatment and Guangxi Universities Key Laboratory of Prevention and Control of Highly Prevalent Disease, Nanning, China
- School of Public Health, Guangxi Medical University, Nanning, China
- Life Science Institute, Guangxi Medical University, Nanning, China
| | - Ping Cui
- Guangxi Key Laboratory of AIDS Prevention and Treatment and Guangxi Universities Key Laboratory of Prevention and Control of Highly Prevalent Disease, Nanning, China
- Life Science Institute, Guangxi Medical University, Nanning, China
| | - Jiegang Huang
- Guangxi Key Laboratory of AIDS Prevention and Treatment and Guangxi Universities Key Laboratory of Prevention and Control of Highly Prevalent Disease, Nanning, China
- School of Public Health, Guangxi Medical University, Nanning, China
| |
Collapse
|
4
|
Liu PY, Ko WC, Lee WS, Lu PL, Chen YH, Cheng SH, Lu MC, Lin CY, Wu TS, Yen MY, Wang LS, Liu CP, Shao PL, Lee YL, Shi ZY, Chen YS, Wang FD, Tseng SH, Lin CN, Chen YH, Sheng WH, Lee CM, Tang HJ, Hsueh PR. In vitro activity of cefiderocol, cefepime/enmetazobactam, cefepime/zidebactam, eravacycline, omadacycline, and other comparative agents against carbapenem-non-susceptible Pseudomonas aeruginosa and Acinetobacter baumannii isolates associated from bloodstream infection in Taiwan between 2018-2020. JOURNAL OF MICROBIOLOGY, IMMUNOLOGY, AND INFECTION = WEI MIAN YU GAN RAN ZA ZHI 2022; 55:888-895. [PMID: 34521591 DOI: 10.1016/j.jmii.2021.08.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Accepted: 08/07/2021] [Indexed: 10/20/2022]
Abstract
BACKGROUND/PURPOSE This study aimed to investigate the in vitro susceptibilities of carbapenem-non-susceptible Pseudomonas aeruginosa (CNSPA) and Acinetobacter baumannii (CNSAB) isolates to cefiderocol, novel β-lactamase inhibitor (BLI) combinations, new tetracycline analogues, and other comparative antibiotics. METHODS In total, 405 non-duplicate bacteremic CNSPA (n = 150) and CNSAB (n = 255) isolates were collected from 16 hospitals in Taiwan between 2018 and 2020. Minimum inhibitory concentrations (MICs) were determined using the broth microdilution method, and susceptibilities were interpreted according to the relevant guidelines or in accordance with results of previous studies and non-species-related pharmacokinetic/pharmacodynamic data. RESULTS Among the isolates tested, cefiderocol demonstrated potent in vitro activity against CNSPA (MIC50/90, 0.25/1 mg/L; 100% of isolates were inhibited at ≤4 mg/L) and CNSAB (MIC50/90, 0.5/2 mg/L; 94.9% of isolates were inhibited at ≤4 mg/L) isolates. More than 80% of CNSPA isolates were susceptible to cefiderocol, ceftazidime/avibactam, ceftolozane/tazobactam, and amikacin, based on breakpoints established by the Clinical and Laboratory Standards Institute. Activities of new BLI combinations varied significantly. Tetracycline analogues, including tigecycline (MIC50/90, 1/2 mg/L; 92.5% of CNSAB isolates were inhibited at ≤2 mg/L) and eravacycline (MIC50/90, 0.5/1 mg/L; 99.6% of CNSAB isolates were inhibited at ≤2 mg/L) exhibited more potent in vitro activity against CNSAB than omadacycline (MIC50/90, 4/8 mg/L). CONCLUSIONS The spread of CNSPA and CNSAB poses a major challenge to global health. Significant resistance be developed even before a novel agent becomes commercially available. The development of on-site antimicrobial susceptibility tests for these novel agents is of great clinical importance.
Collapse
Affiliation(s)
- Po-Yu Liu
- Department of Internal Medicine, Taichung Veterans General Hospital, Taichung, Taiwan
| | - Wen-Chien Ko
- Department of Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Wen-Sen Lee
- Division of Infectious Diseases, Department of Internal Medicine, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan; Department of Internal Medicine, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Po-Liang Lu
- Department of Internal Medicine, Kaohsiung Medical University Hospital, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Yen-Hsu Chen
- Department of Internal Medicine, Kaohsiung Medical University Hospital, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Shu-Hsing Cheng
- Department of Internal Medicine, Taoyuan General Hospital, Ministry of Health and Welfare, Taoyuan, Taiwan; School of Public Health, College of Public Health and Nutrition, Taipei Medical University, Taipei, Taiwan
| | - Min-Chi Lu
- Department of Microbiology and Immunology, School of Medicine, China Medical University, Taichung, Taiwan
| | - Chi-Ying Lin
- Department of Internal Medicine, National Taiwan University Hospital Yunlin Branch, Yunlin, Taiwan
| | - Ting-Shu Wu
- Division of Infectious Diseases, Department of Internal Medicine, Chang Gung Memorial Hospital at Linkou, Chang Gung University College of Medicine, Taoyuan, Taiwan
| | - Muh-Yong Yen
- Division of Infectious Diseases, Taipei City Hospital, National Yang-Ming University, School of Medicine, Taipei, Taiwan
| | - Lih-Shinn Wang
- Division of Infectious Diseases, Department of Internal Medicine, Buddhist Tzu Chi General Hospital, Hualien, Taiwan; Tzu Chi University, Hualien, Taiwan
| | - Chang-Pan Liu
- Division of Infectious Diseases, Department of Internal Medicine, MacKay Memorial Hospital, Taipei, Taiwan; MacKay Medical College, New Taipei City, Taiwan
| | - Pei-Lan Shao
- Department of Pediatrics, Hsin-Chu Branch, National Taiwan University Hospital, Hsin-Chu, Taiwan
| | - Yu-Lin Lee
- Department of Internal Medicine, Changhua Christian Hospital, Changhua, Taiwan; Institute of Genomics and Bioinformatics, National Chung Hsing University, Taichung, Taiwan
| | - Zhi-Yuan Shi
- Department of Internal Medicine, Taichung Veterans General Hospital, Taichung, Taiwan
| | - Yao-Shen Chen
- Department of Internal Medicine, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan; School of Medicine, National Yang-Ming University, Taipei, Taiwan
| | - Fu-Der Wang
- Division of Infectious Diseases, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan; School of Medicine, National Yang-Ming University, Taipei, Taiwan
| | - Shu-Hui Tseng
- Center for Disease Control and Prevention, Ministry of Health and Welfare, Taiwan
| | - Chao-Nan Lin
- Department of Veterinary Medicine, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, Taiwan; Animal Disease Diagnostic Center, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, Taiwan
| | - Yu-Hui Chen
- Infection Control Center, Chi Mei Hospital, Liouying, Taiwan
| | - Wang-Huei Sheng
- Division of Infectious Diseases, Department of Internal Medicine, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Chun-Ming Lee
- Department of Internal Medicine, St Joseph's Hospital, Yunlin County, Taiwan; MacKay Junior College of Medicine, Nursing, and Management, Taipei, Taiwan
| | - Hung-Jen Tang
- Department of Medicine, Chi Mei Medical Center, Tainan, Taiwan
| | - Po-Ren Hsueh
- Division of Infectious Diseases, Department of Internal Medicine, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan; Department of Laboratory Medicine, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan; Departments of Laboratory Medicine and Internal Medicine, China Medical University Hospital, School of Medicine, China Medical University, Taichung, Taiwan.
| |
Collapse
|
5
|
Chien YC, Huang YT, Liao CH, Chien JY, Hsueh PR. Clinical characteristics of bacteremia caused by Haemophilus and Aggregatibacter species and antimicrobial susceptibilities of the isolates. JOURNAL OF MICROBIOLOGY, IMMUNOLOGY, AND INFECTION = WEI MIAN YU GAN RAN ZA ZHI 2021; 54:1130-1138. [PMID: 33390332 DOI: 10.1016/j.jmii.2020.12.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 12/13/2020] [Accepted: 12/14/2020] [Indexed: 12/17/2022]
Abstract
BACKGROUND/PURPOSE This study aimed to investigate the clinical characteristics and outcomes of bacteremia caused by Haemophilus and Aggregatibacter species in patients who were treated at a medical center between 2006 and 2018. METHODS Haemophilus and Aggregatibacter isolates were identified up to the species level using Bruker Biotyper MALDI-TOF analysis and ancillary 16S rRNA gene sequencing analysis (in case of ambiguity). Clinical characteristics and outcomes of patients with bacteremia caused by these organisms were evaluated. RESULTS Sixty-five Haemophilus and Aggregatibacter species isolates causing bacteremia were identified from nonduplicated patients, including 51 (78.5%) Haemophilus influenzae, 6 (9.2%) Haemophilus parainfluenzae, 1 (1.5%) Haemophilus haemolyticus, 3 (4.6%) A. aphrophilus, and 4 (6.2%) A. segnis. Hospital mortality was observed in 18 (28.1%) of 64 patients with bacteremia caused by Haemophilus (n = 57) and Aggregatibacter species (n = 7). The majority of patients with bacteremia had community-acquired disease with low severity. The average Sequential Organ Failure Assessment (SOFA) score was low (4.4 ± 4.7). But, a higher SOFA score (adjusted odds ratio 2.5, 95% confidence interval 1.22-5.12; P = 0.01) was an independent factor predicting poor 7-day clinical outcomes in patients with community-acquired H. influenzae bacteremia (n = 39). CONCLUSIONS The overall hospital mortality of 28.1% was observed among patients with bacteremia due to Haemophilus and Aggregatibacter species. A higher SOFA score was and independent predictor of poor 7-day clinical outcomes in patients with community-acquired H. influenzae bacteremia.
Collapse
Affiliation(s)
- Ying-Chun Chien
- Department of Internal Medicine, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan; Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Yu-Tsung Huang
- Department of Laboratory Medicine, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan; Division of Infectious Diseases, Far Eastern Memorial Hospital, New Taipei City, Taiwan
| | - Chun-Hsing Liao
- Division of Infectious Diseases, Far Eastern Memorial Hospital, New Taipei City, Taiwan; Department of Medicine, Yang-Ming University, Taipei, Taiwan
| | - Jung-Yien Chien
- Department of Internal Medicine, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Po-Ren Hsueh
- Department of Internal Medicine, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan; Department of Laboratory Medicine, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan.
| |
Collapse
|
6
|
Abstract
Gram-negative bacteremia is a devastating public health threat, with high mortality in vulnerable populations and significant costs to the global economy. Concerningly, rates of both Gram-negative bacteremia and antimicrobial resistance in the causative species are increasing. Gram-negative bacteremia develops in three phases. First, bacteria invade or colonize initial sites of infection. Second, bacteria overcome host barriers, such as immune responses, and disseminate from initial body sites to the bloodstream. Third, bacteria adapt to survive in the blood and blood-filtering organs. To develop new therapies, it is critical to define species-specific and multispecies fitness factors required for bacteremia in model systems that are relevant to human infection. A small subset of species is responsible for the majority of Gram-negative bacteremia cases, including Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter baumannii The few bacteremia fitness factors identified in these prominent Gram-negative species demonstrate shared and unique pathogenic mechanisms at each phase of bacteremia progression. Capsule production, adhesins, and metabolic flexibility are common mediators, whereas only some species utilize toxins. This review provides an overview of Gram-negative bacteremia, compares animal models for bacteremia, and discusses prevalent Gram-negative bacteremia species.
Collapse
Affiliation(s)
- Caitlyn L Holmes
- Department of Pathology, University of Michigan Medical School, Ann Arbor, Michigan, USA
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Mark T Anderson
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Harry L T Mobley
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Michael A Bachman
- Department of Pathology, University of Michigan Medical School, Ann Arbor, Michigan, USA
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| |
Collapse
|