Takeshi Tanaka

Bio: Takeshi Tanaka is an academic researcher from Osaka University. The author has contributed to research in topics: ARDS & Medicine. The author has an hindex of 1, co-authored 1 publications receiving 12 citations.

Non-nosocomial healthcare-associated left-sided Pseudomonas aeruginosa endocarditis: a case report and literature review.

Abstract: With the development of invasive medical procedures, an increasing number of healthcare-associated infective endocarditis cases have been reported. In particular, non-nosocomial healthcare-associated infective endocarditis in outpatients with recent medical intervention has been increasingly identified. A 66-year-old man with diabetes mellitus and a recent history of intermittent urethral self-catheterization was admitted due to a high fever. Repeated blood cultures identified Pseudomonas aeruginosa, and transesophageal echocardiography uncovered a new-onset severe aortic regurgitation along with a vegetative valvular structure. The patient underwent emergency aortic valve replacement surgery and was successfully treated with 6 weeks of high-dose meropenem and tobramycin. Historically, most cases of P. aeruginosa endocarditis have occurred in the right side of the heart and in outpatients with a history of intravenous drug abuse. In the case presented, the repeated manipulations of the urethra may have triggered the infection. Our literature review for left-sided P. aeruginosa endocarditis showed that non-nosocomial infection accounted for nearly half of the cases and resulted in fatal outcomes as often as nosocomial cases. A combination therapy with anti-pseudomonal beta-lactams or carbapenems and aminoglycosides may be the preferable treatment. Medical treatment alone may be effective, and surgical treatment should be carefully considered. We presented a rare case of native aortic valve endocarditis caused by P. aeruginosa. This case illustrates the importance of identifying the causative pathogen(s), especially for outpatients with a recent history of medical procedures.

ARDS Clinical Practice Guideline 2021

Abstract: The joint committee of the Japanese Society of Intensive Care Medicine/Japanese Respiratory Society/Japanese Society of Respiratory Care Medicine on ARDS Clinical Practice Guideline has created and released the ARDS Clinical Practice Guideline 2021.The 2016 edition of the Clinical Practice Guideline covered clinical questions (CQs) that targeted only adults, but the present guideline includes 15 CQs for children in addition to 46 CQs for adults. As with the previous edition, we used a systematic review method with the Grading of Recommendations Assessment Development and Evaluation (GRADE) system as well as a degree of recommendation determination method. We also conducted systematic reviews that used meta-analyses of diagnostic accuracy and network meta-analyses as a new method.Recommendations for adult patients with ARDS are described: we suggest against using serum C-reactive protein and procalcitonin levels to identify bacterial pneumonia as the underlying disease (GRADE 2D); we recommend limiting tidal volume to 4-8 mL/kg for mechanical ventilation (GRADE 1D); we recommend against managements targeting an excessively low SpO2 (PaO2) (GRADE 2D); we suggest against using transpulmonary pressure as a routine basis in positive end-expiratory pressure settings (GRADE 2B); we suggest implementing extracorporeal membrane oxygenation for those with severe ARDS (GRADE 2B); we suggest against using high-dose steroids (GRADE 2C); and we recommend using low-dose steroids (GRADE 1B). The recommendations for pediatric patients with ARDS are as follows: we suggest against using non-invasive respiratory support (non-invasive positive pressure ventilation/high-flow nasal cannula oxygen therapy) (GRADE 2D), we suggest placing pediatric patients with moderate ARDS in the prone position (GRADE 2D), we suggest against routinely implementing NO inhalation therapy (GRADE 2C), and we suggest against implementing daily sedation interruption for pediatric patients with respiratory failure (GRADE 2D).This article is a translated summary of the full version of the ARDS Clinical Practice Guideline 2021 published in Japanese (URL: https://www.jsicm.org/publication/guideline.html ). The original text, which was written for Japanese healthcare professionals, may include different perspectives from healthcare professionals of other countries.

Complications of a lung biopsy for severe respiratory failure: A systematic review and meta-analysis

Abstract: This systematic review and meta-analysis aimed to evaluate the complications of lung biopsy in patients with acute respiratory failure (ARF), including acute respiratory distress syndrome (ARDS). We searched the MEDLINE and Cochrane Central Register of Controlled Trials. The primary outcomes were biopsy-related death, respiratory failure, cardiac complications, bleeding, and other major complications. We used the McMaster Quality Assessment Scale of Harms (McHarm) to evaluate the risk of bias. A random-effects model was used to calculate the pooled frequencies. Thirteen studies (consisting of 574 patients) were included in the meta-analysis. Furthermore, most of the included studies had a high or unclear risk of bias in half of the items in McHarm. All included studies evaluated surgical lung biopsies. The median overall hospital mortality was 53% (range: 17%–90%). The pooled frequencies of biopsy-related death, respiratory failure, cardiac complication, bleeding, and other major complications were 0.00% (95% confidence interval [CI]: 0.00%–0.21%), 1.30% (95% CI: 0.00%–5.69%), 1.03% (95% CI: 0.00%–3.73%), 1.46% (95% CI: 0.16%–3.56%), and 4.26% (95% CI: 0.00%–13.0%), respectively. The results of this study will be valuable information in considering the indications of lung biopsy in patients with ARF, including ARDS. The protocol was registered with the University Hospital Medical Information Network Clinical Trials Registry (UMIN 000040650).

Pseudomonas aeruginosa Quorum Sensing Systems as Drug Discovery Targets: Current Position and Future Perspectives.

Abstract: Antimicrobial resistance (AMR) is a serious threat to public health globally, manifested by the frequent emergence of multidrug resistant pathogens that render current chemotherapy inadequate. Health organizations worldwide have recognized the severity of this crisis and implemented action plans to contain its adverse consequences and prolong the utility of conventional antibiotics. Hence, there is a pressing need for new classes of antibacterial agents with novel modes of action. Quorum sensing (QS), a communication system employed by bacterial populations to coordinate virulence gene expression, is a potential target that has been intensively investigated over the past decade. This Perspective will focus on recent advances in targeting the three main quorum sensing systems (las, rhl, and pqs) of a major opportunistic human pathogen, Pseudomonas aeruginosa, and will specifically evaluate the medicinal chemistry strategies devised to develop QS inhibitors from a drug discovery perspective.

Compassionate Use of Cefiderocol as Adjunctive Treatment of Native Aortic Valve Endocarditis Due to Extremely Drug-resistant Pseudomonas aeruginosa.

Abstract: Serious infections such as endocarditis due to extremely drug-resistance gram-negative bacteria are an increasing challenge. Here, we present successful adjunctive use of cefiderocol for a patient with persistently bacteremic healthcare-associated native aortic valve endocarditis due to an extended-spectrum beta-lactamase-positive Pseudomonas aeruginosa susceptible in vitro only to colistin, following failure of conventional therapeutic options.

Emergence of Antimicrobial Resistance among Pseudomonas aeruginosa: Implications for Therapy.

Abstract: Pseudomonas aeruginosa (PA), a nonlactose fermenting gram-negative bacillus, is a common cause of nosocomial infections in critically ill or debilitated patients, particularly ventilator-associated pneumonia (VAP), and infections of bloodstream, urinary tract, intra-abdominal, wounds/skin/soft tissue PA rarely affects healthy individuals, but may cause serious infections in patients with chronic structural lung disease, comorbidities, advanced age, impaired immune defenses, or with medical devices (eg, urinary or intravascular catheters, foreign bodies) Treatment of pseudomonal infections is difficult, as PA is intrinsically resistant to multiple antimicrobials, and may acquire new resistance determinants even while on antimicrobial therapy Mortality associated with pseudomonal VAP or bacteremias is high (> 35%) and optimal therapy is controversial Over the past three decades, antimicrobial resistance among PA has escalated globally, via dissemination of several international multidrug-resistant “epidemic” clones We review the emergence of antimicrobial resistance to this pathogen, and discuss approaches to therapy (both empirical and definitive)

Prosthetic valve endocarditis caused by Pseudomonas aeruginosa with variable antibacterial resistance profiles: a diagnostic challenge.

Abstract: Infective endocarditis (IE) caused by gram-negative bacilli is rare. However, the incidence of this severe infection is rising because of the increasing number of persons at risk, such as patients with immunosuppression or with cardiac implantable devices and prosthetic valves. The diagnosis of IE is often difficult, particularly when microorganisms such as Pseudomonas aeruginosa, which rarely cause this infection, are involved. One of the mainstays for the diagnosis of IE are persistently positive blood cultures with the same bacteria, while polymicrobial bacteremia usually points to another cause, e.g. an abscess. The antimicrobial resistance profile of some P. aeruginosa strains may change, falsely suggesting an infection with several strains, thus further increasing the diagnostic difficulties. A 66-year old male patient who had a transcatheter aortic valve implantation (TAVI) one year previously developed fever seven days after an elective inguinal hernia repair. During the following four weeks, P. aeruginosa with different antibiotic resistance profiles was repeatedly isolated from blood cultures. Repeated trans-esophageal echocardiograms (TEE) were negative and an infection by different P. aeruginosa strains was suspected. Extensive diagnostic workup for an infectious focus was performed with no results. Finally, an oscillating mass on the aortic valve was detected by TEE five weeks after the initial positive blood cultures. P. aeruginosa endocarditis was confirmed by culture of the surgically removed valve. Whole genome sequencing of the last two P. aeruginosa isolates (valve and blood culture) revealed identical strains, with genome mutations for AmpR, AmpD and OprD. The diagnosis of prosthetic valve endocarditis is particularly difficult for several reasons. The modified Duke criteria have a lower sensitivity for patients with prosthetic valve endocarditis and the infection may be caused by “unusual” pathogens such as P. aeruginosa. Patients with repeatedly positive blood cultures should make clinicians suspicious for endocarditis even if imaging studies are negative and if isolated pathogens are “unusual”. Repeatedly positive blood cultures for P. aeruginosa should be considered as “persistent bacteremia” (suspicious for IE) even in the presence of different antibiotic susceptibility patterns, since P. aeruginosa might rapidly activate or deactivate resistance mechanisms depending on antibiotic exposition.

The Sequential Organ Failure Assessment (SOFA) Score: has the time come for an update?

Abstract: The Sequential Organ Failure Assessment (SOFA) score was developed more than 25 years ago to provide a simple method of assessing and monitoring organ dysfunction in critically ill patients. Changes in clinical practice over the last few decades, with new interventions and a greater focus on non-invasive monitoring systems, mean it is time to update the SOFA score. As a first step in this process, we propose some possible new variables that could be included in a SOFA 2.0. By so doing, we hope to stimulate debate and discussion to move toward a new, properly validated score that will be fit for modern practice.