Efficacy of Blind Tracheal Aspirate in Comparison to Bronchoalveolar Lavage for Microbiological Diagnosis of Nosocomial Pneumonia in Patients on Ventilator

Background and Objectives: For diagnosis of nosocomial pneumonia in patients on ventilator, invasive procedure like bronchoscopy for microscopy and quantitative cultures of lower respiratory tract samples is useful but not always possible for potential risk of the procedure and the associated cost. The non-bronchoscopic sampling of the lower airways and quantitative cultures of tracheal aspirate may offer simple and readily available alternative to bronchoscopy with promising results. This study was done to evaluate the efficacy of blind tracheal aspirate in the microbiological diagnosis of nosocomial pneumonia occurring in intubated patients on mechanical ventilator. Materials & Methods: This cross-sectional study was carried out in the Intensive Care Unit in the Department of Critical Care Medicine, BIRDEM Hospital, Dhaka over a period 16 months starting from January 2010 to April 2011. A total of 54 clinically diagnosed cases of nosocomial (hospital acquired) pneumonia who were on ventilator were consecutively included in the study based on predefined enrolment criteria. All the 54 cases were subjected to blind endotracheal aspirate (BTA) followed by bronchoalveolar lavage (BAL) for quantitative cultures of specimens and isolation of causative microorganisms from them. Result: The present study showed that the mean age of the patients was 61 years (range: 24-86 years). Males were predominant in the series with male to female ratio being 7:3. Majority of the patients was haemodynamically stable as indicated by mean blood pressures, heart rate, temperature and respiratory rate. Most (83.3%) of the cases showed significant growth of microbes on culture of blind tracheal aspirates at cut-off value of 105 colony forming unit/ml (cfu/ml), while 87% of the cases exhibited positive growth on culture of bronchoalveolar lavage at cut-off value of 104 cfu/ml. Acinetobacter baumannii was the predominant organism isolated from BTA (73.3%) followed by Pseudomonas aeruginosa (33.3%). An almost similar pattern of growth was evident in BAL with more than 70% being Acinetobacter baumannii and about 30% Pseudomonas aeruginosa. C. albicans. Kiebsiella sp., E. coli, and Flavobacter were less commonly observed in either group. The Kappa test revealed a good agreement (70.7%) between the two procedures suggesting that the two diagnostic modalities are almost comparable in diagnosing pneumonia in patients admitted in ICU (p < 0.001). Conclusion: The study concluded that the accuracy of blind tracheal aspirate and bronchalveolar lavage in the diagnosis of nosocomial pneumonia was fairly comparable. The strength of agreement between the two diagnostic modalities is also good encouraging its use instead of more invasive procedures like BAL in the diagnosis of hospital-acquired pneumonia who are on mechanical ventilator. Ibrahim Cardiac Med J 2014; 4(2): 49-55

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Antimicrobial-resistant Pseudomonas aeruginosa and Acinetobacter baumannii From Patients With Hospital-acquired or Ventilator-associated Pneumonia in Vietnam

Clinical Therapeutics ◽

10.1016/j.clinthera.2016.07.172 ◽

2016 ◽

Vol 38 (9) ◽

pp. 2098-2105 ◽

Cited By ~ 7

Author(s):

Douglas J. Biedenbach ◽

Phan Trong Giao ◽

Pham Hung Van ◽

Nguyen Su Minh Tuyet ◽

Tran Thi Thanh Nga ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Acinetobacter Baumannii ◽

Ventilator Associated Pneumonia ◽

Hospital Acquired

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Hospital-Acquired Pneumonia = Nosocomial Pneumonia

Encyclopedia of Intensive Care Medicine ◽

10.1007/978-3-642-00418-6_1710 ◽

2012 ◽

pp. 1152-1152

Author(s):

Jeffrey N. Harr ◽

Philip F. Stahel ◽

Phillip D. Levy ◽

Antoine Vieillard-Baron ◽

Yang Xue ◽

...

Keyword(s):

Nosocomial Pneumonia ◽

Hospital Acquired Pneumonia ◽

Hospital Acquired

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Acinetobacter baumannii lipopolysaccharides are potent stimulators of human monocyte activation via Toll-like receptor 4 signalling

Journal of Medical Microbiology ◽

10.1099/jmm.0.46823-0 ◽

2007 ◽

Vol 56 (2) ◽

pp. 165-171 ◽

Cited By ~ 65

Author(s):

Clett Erridge ◽

Olga L. Moncayo-Nieto ◽

Robert Morgan ◽

Michelle Young ◽

Ian R. Poxton

Keyword(s):

Acinetobacter Baumannii ◽

Human Monocyte ◽

Toll Like Receptor 4 ◽

Necrosis Factor Alpha ◽

Hek 293 ◽

293 Cells ◽

Hospital Acquired Pneumonia ◽

Factor Alpha ◽

Hospital Acquired ◽

Inflammatory Signalling

Acinetobacter baumannii is a major nosocomial pathogen and frequent cause of hospital-acquired pneumonia, surgical wound infections and sepsis. As very little is known of the endotoxic potential of A. baumannii lipopolysaccharide (LPS) with respect to human cells or of its ability to stimulate inflammatory signalling via human Toll-like receptors (TLRs), the biological activity of these endotoxins was investigated in human monocytic THP-1 cells and in TLR-deficient HEK-293 cells transfected with human TLR2 and TLR4 constructs. Endotoxins derived from five clinical isolates of A. baumannii and one of Acinetobacter ‘genomospecies 9’ showed high potency, which was comparable to that of Escherichia coli strain R1 NCTC 13114 LPS, in the induction of the Limulus amoebocyte reaction and interleukin 8 and tumour necrosis factor alpha release from THP-1 cells. Whole UV-killed cells of A. baumannii and Acinetobacter ‘genomospecies 9’ stimulated both TLR2- and TLR4-dependent signalling, whereas pure endotoxins of all investigated strains induced signalling via TLR4, but not TLR2.

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Pneumonia

10.1093/med/9780199568741.003.0129 ◽

2018 ◽

Author(s):

Pippa Newton

Keyword(s):

Nosocomial Pneumonia ◽

Acute Infection ◽

Healthcare Setting ◽

Community Acquired Pneumonia ◽

Hospital Acquired Pneumonia ◽

Pulmonary Parenchyma ◽

Post Intubation ◽

Hospital Acquired ◽

Symptoms And Signs

Pneumonia is defined as acute infection of the pulmonary parenchyma, presenting with consistent symptoms and signs and associated with new radiographic shadowing. It may be acute or chronic in onset and involve either one area of a lung (e.g. lobar pneumonia) or be multifocal in nature. It may be community acquired or hospital acquired. Community- acquired pneumonia is defined as pneumonia occurring in an individual with no recent contact with a healthcare setting, or in a patient admitted to hospital with development of symptoms and/or signs of pneumonia within 48 hours of admission. Hospital-acquired pneumonia or nosocomial pneumonia occurs when a patient develops symptoms or signs of pneumonia after 48 hours of admission to a healthcare setting or in the context of a long-term nursing home resident. A subtype of nosocomial pneumonia is ventilator-associated pneumonia, defined as pneumonia occurring at least 48–72 hours post intubation.

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In Vitro Comparison of Ceftolozane-Tazobactam to Traditional Beta-Lactams and Ceftolozane-Tazobactam as an Alternative to Combination Antimicrobial Therapy for Pseudomonas aeruginosa

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01350-17 ◽

2017 ◽

Vol 61 (12) ◽

Cited By ~ 16

Author(s):

Kellie J. Goodlet ◽

David P. Nicolau ◽

Michael D. Nailor

Keyword(s):

Pseudomonas Aeruginosa ◽

Single Agent ◽

Cross Resistance ◽

Combination Therapies ◽

Beta Lactams ◽

Content Type ◽

Risk Patients ◽

Hospital Acquired Pneumonia ◽

Hospital Acquired

ABSTRACT Guidelines for the treatment of sepsis, febrile neutropenia, and hospital-acquired pneumonia caused by Pseudomonas aeruginosa include empirical regimens incorporating two antibiotics from different classes with activity against P. aeruginosa for select at-risk patients to increase the likelihood that the organism will be susceptible to at least one agent. The activity against P. aeruginosa and the rates of cross-resistance of ceftolozane-tazobactam were compared to those of the β-lactam comparators cefepime, ceftazidime, piperacillin-tazobactam, and meropenem alone and cumulatively with ciprofloxacin or tobramycin. Nonurine P. aeruginosa isolates were collected from adult inpatients at 44 geographically diverse U.S. hospitals. MICs were determined using reference broth microdilution methods. Of the 1,257 isolates collected, 29% were from patients in intensive care units and 39% were from respiratory sites. The overall rate of susceptibility to ceftolozane-tazobactam was high at 97%, whereas it was 72 to 76% for cefepime, ceftazidime, piperacillin-tazobactam, and meropenem. The rate of nonsusceptibility to all four comparator β-lactams was 11%; of the isolates nonsusceptible to the four comparator β-lactams, 80% remained susceptible to ceftolozane-tazobactam. Among the isolates nonsusceptible to the tested β-lactam comparators, less than half were susceptible to ciprofloxacin. By comparison, approximately 80% of the β-lactam-nonsusceptible isolates were susceptible to tobramycin, for overall cumulative susceptibility rates of 94 to 95%, nearly 10% higher than that of the ciprofloxacin–β-lactam combinations and approaching that of ceftolozane-tazobactam as a single agent. The rates of susceptibility to ceftolozane-tazobactam were consistently high, with little observable cross-resistance. Ceftolozane-tazobactam monotherapy performed at or above the level of commonly utilized combination therapies on the basis of in vitro susceptibilities. Ceftolozane-tazobactam should be considered for use in patients at high risk for resistant P. aeruginosa infection and as an alternative to empirical combination therapy, especially for patients unable to tolerate aminoglycosides.

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Invasive and non-invasive diagnostic approaches for microbiological diagnosis of hospital-acquired pneumonia

Critical Care ◽

10.1186/s13054-019-2348-2 ◽

2019 ◽

Vol 23 (1) ◽

Cited By ~ 4

Author(s):

Otavio T. Ranzani ◽

Tarek Senussi ◽

Francesco Idone ◽

Adrian Ceccato ◽

Gianluigi Li Bassi ◽

...

Keyword(s):

Microbiological Diagnosis ◽

Non Invasive ◽

Hospital Acquired Pneumonia ◽

Diagnostic Approaches ◽

Hospital Acquired

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Antimicrobial Activity of Ceftolozane–Tazobactam Tested against Contemporary (2012–2016) Enterobacteriaceae and Pseudomonas aeruginosa from ICU vs. non-ICU Isolates Collected in US Medical Centers

Open Forum Infectious Diseases ◽

10.1093/ofid/ofx163.894 ◽

2017 ◽

Vol 4 (suppl_1) ◽

pp. S366-S366

Author(s):

Dee Shortridge ◽

Leonard R Duncan ◽

Michael A Pfaller ◽

Robert K Flamm

Keyword(s):

Pseudomonas Aeruginosa ◽

The United States ◽

Icu Patients ◽

Medical Centers ◽

Hospital Acquired Pneumonia ◽

Tract Infections ◽

Abdominal Infections ◽

Hospital Acquired ◽

Lactamase Inhibitor ◽

Research Grant

Abstract Background Ceftolozane-tazobactam (C-T) is a combination of a novel antipseudomonal cephalosporin and a well-described β-lactamase inhibitor. C-T was approved by the United States (US) Food and Drug Administration in 2014 for complicated urinary tract infections, including acute pyelonephritis and complicated intra-abdominal infections. C-T is currently in clinical trials for the treatment of hospital-acquired pneumonia. The Program to Assess Ceftolozane-Tazobactam Susceptibility (PACTS) monitors C-T resistance to gram-negative (GN) isolates worldwide. This study compares the activities of C-T and comparators against GN isolates from ICU patients and non-ICU patients. Methods A total of 3,100 GN ICU isolates and 3,271 isolates from non-ICU patients were collected from 30 US hospitals in 2012–2016. Isolates were tested for susceptibility (S) to C-T and comparators by CLSI broth microdilution methodology in a central monitoring laboratory. Other antibiotics tested included amikacin (AMK), cefepime (FEP), ceftazidime (CAZ), colistin (COL), meropenem (MER), and piperacillin-tazobactam (TZP). CLSI (2017) interpretive criteria were used for all except COL with Enterobacteriaceae (ENT), for which EUCAST (2017) criteria were used. Results The most common ENT species from ICU and non-ICU patients were similar. The 3 most common ENT for ICU and non-ICU isolates were Klebsiella pneumoniae, 24.1% and 25.8%; Escherichia coli, 19.4% and 18.2%; and Serratia marcescens, 14.7% and 14.3%, respectively. The most common non-enteric species was Pseudomonas aeruginosa (PSA) for ICU and non-ICU (72.7% and 78.2%). ICU ENT isolates generally had a lower %S than non-ICU (Table). ENT showed more variability than PSA for %S between ICU and non-ICU. Conclusion For ENT overall, MER and AMK were the most active, followed by C-T. Comparing ICU and non-ICU, MER and C-T were slightly more active vs. non-ICU ENT, while AMK %S was similar for both. For PSA, COL was the most active; C-T and AMK were similar. Activities between ICU and non-ICU isolates were similar for C-T and COL while AMK was more active vs. ICU isolates, and MER was more active vs. non-ICU. C-T showed potent activity against ICU and non-ICU isolates for ENT and PSA. Disclosures D. Shortridge, Merck: Research Contractor, Research grant; L. R. Duncan, Merck: Research Contractor, Research grant; M. A. Pfaller, Merck: Research Contractor, Research grant; R. K. Flamm, Merck: Research Contractor, Research grant

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Clinical experience with tigecycline in the treatment of hospital-acquired pneumonia caused by multidrug resistant Acinetobacter baumannii

BMC Pharmacology and Toxicology ◽

10.1186/s40360-019-0300-3 ◽

2019 ◽

Vol 20 (1) ◽

Cited By ~ 3

Author(s):

Yangang Zhou ◽

Xumin Chen ◽

Ping Xu ◽

Yan Zhu ◽

Kuangguo Wang ◽

...

Keyword(s):

Acinetobacter Baumannii ◽

Clinical Experience ◽

Multidrug Resistant ◽

Hospital Acquired Pneumonia ◽

Hospital Acquired

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Pseudomonas aeruginosa Induces Localized Immunosuppression during Pneumonia

Infection and Immunity ◽

10.1128/iai.00012-08 ◽

2008 ◽

Vol 76 (10) ◽

pp. 4414-4421 ◽

Cited By ~ 57

Author(s):

Maureen H. Diaz ◽

Ciara M. Shaver ◽

John D. King ◽

Srinidhi Musunuri ◽

Jeffrey A. Kazzaz ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Bacterial Pneumonia ◽

Pathogenic Bacteria ◽

Innate Immune ◽

Pulmonary Infections ◽

Phagocytic Cells ◽

Local Immunosuppression ◽

Hospital Acquired Pneumonia ◽

Mouse Model Of Infection ◽

Hospital Acquired

ABSTRACT Hospital-acquired bacterial pneumonia is a common and serious complication of modern medical care. Many aspects of such infections remain unclear, including the mechanisms by which invading pathogens resist clearance by the innate immune response and the tendency of the infections to be polymicrobial. Here, we used a mouse model of infection to show that Pseudomonas aeruginosa, a leading cause of hospital-acquired pneumonia, interferes with the ability of recruited phagocytic cells to eradicate bacteria from the lung. Early in infection, phagocytic cells, predominantly neutrophils, are recruited to the lungs but are incapacitated when they enter the airways by the P. aeruginosa toxin ExoU. The resulting paucity of functioning phagocytes allows P. aeruginosa to persist within the lungs and results in local immunosuppression that facilitates superinfection with less-pathogenic bacteria. Together, our results provide explanations for previous reports linking ExoU-secreting P. aeruginosa with more severe pulmonary infections and for the tendency of hospital-acquired pneumonia to be polymicrobial.

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