Utility of pneumonia severity assessment tools for mortality prediction in healthcare-associated pneumonia: a systematic review and meta-analysis.

Accurate prognostic tools for mortality in patients with healthcare-associated pneumonia (HCAP) are needed to provide appropriate medical care, but the efficacy for mortality prediction of tools like PSI, A-DROP, I-ROAD, and CURB-65, widely used for predicting mortality in community-acquired and hospital-acquired pneumonia cases, remains controversial. In this study, we conducted a systematic review and meta-analysis using PubMed, Cochrane Library (trials), and Ichushi web database (accessed on August 22, 2022). We identified articles evaluating either PSI, A-DROP, I-ROAD, or CURB-65 and the mortality outcome in patients with HCAP, and calculated the pooled sensitivities, specificities, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and the summary area under the curves (AUCs) for mortality prediction. Additionally, the differences in predicting prognosis among these four assessment tools were evaluated using overall AUCs pooled from AUC values reported in included studies. Eventually, 21 articles were included and these quality assessments were evaluated by QUADAS-2. Using a cut-off value of moderate in patients with HCAP, the range of pooled sensitivity, specificity, PLR, NLR, and DOR were found to be 0.91-0.97, 0.15-0.44, 1.14-1.66, 0.18-0.33, and 3.86-9.32, respectively. Upon using a cut-off value of severe in those patients, the range of pooled sensitivity, specificity, PLR, NLR, and DOR were 0.63-0.70, 0.54-0.66, 1.50-2.03, 0.47-0.58, and 2.66-4.32, respectively. Overall AUCs were 0.70 (0.68-0.72), 0.70 (0.63-0.76), 0.68 (0.64-0.73), and 0.67 (0.63-0.71), respectively, for PSI, A-DROP, I-ROAD, and CURB-65 (p = 0.66). In conclusion, these severity assessment tools do not have enough ability to predict mortality in HCAP patients. Furthermore, there are no significant differences in predictive performance among these four severity assessment tools.

Nationwide surveillance of bacterial respiratory pathogens conducted by the surveillance committee of the Japanese Society of Chemotherapy, the Japanese Association for Infectious Diseases, and the Japanese Society for Clinical Microbiology in 2019-2020: General view of the pathogens' antibacterial susceptibility.

The trends and prevalence of antimicrobial susceptibility of pathogens vary by country, region, and time. Long-term regular surveillance is required to investigate trends in the antimicrobial resistance of various isolated bacterial pathogens. We report the results of a nationwide surveillance on the antimicrobial susceptibility of bacterial respiratory pathogens in Japan conducted by the Japanese Society of Chemotherapy, the Japanese Association for Infectious Diseases, and the Japanese Society for Clinical Microbiology. The isolates were collected from clinical specimens obtained from adult patients who visited a collaborating medical facility between June 2019 and December 2020 and were diagnosed with respiratory tract infections by a physician. Antimicrobial susceptibility testing was performed in a centralized laboratory according to the methods recommended by the Clinical and Laboratory Standards Institute. Susceptibility testing was performed for 932 strains (201 Staphylococcus aureus, 158 Streptococcus pneumoniae, 6 S. pyogenes, 136 Haemophilus influenzae, 127 Moraxella catarrhalis, 141 Klebsiella pneumoniae, and 163 Pseudomonas aeruginosa) collected from 32 facilities in Japan. The proportions of methicillin-resistant S. aureus and penicillin-resistant S. pneumoniae were 35.3% and 0%, respectively. In H. influenzae, 16.2% and 16.9% were ß-lactamase-producing ampicillin resistant and ß-lactamase-negative ampicillin resistant, respectively. Extended-spectrum ß-lactamase-producing K. pneumoniae accounted for 5.0% of all K. pneumoniae infections. Carbapenemase-producing K. pneumoniae and multi-drug-resistant P. aeruginosa with metallo-ß-lactamase were not detected in this study. This surveillance will be a useful reference for treating respiratory infections in Japan and will provide evidence to enhance the appropriate use of antimicrobial agents.

Prospective multicenter survey for Nursing and Healthcare-associated Pneumonia in Japan.

INTRODUCTION: Nursing and healthcare-associated pneumonia (NHCAP) was proposed by the Japanese Respiratory Society in 2011. However, the clinical characteristics of NHCAP are still unclear. Thus, this study aimed to clarify its clinical characteristics. METHODS: This multicenter prospective observational study included 596 patients with NHCAP from 73 centers in Japan between May 2014 and February 2016. RESULTS: Patient background was characterized by an older age (81.5 ± 10.1 years), most patients had complications (94.1%), and many patients had a high probability of aspiration pneumonia (68.6%). Among the isolates, Streptococcus pneumoniae was the most common (12.7%), while Pseudomonas aeruginosa was also isolated at 10.8%. The overall 30-day mortality rate for patients was 11.9%, and the factors affecting mortality were non-ambulatory status, high blood urea nitrogen level, impaired consciousness, and low albumin level. Sulbactam/ampicillin was the most commonly administered antibiotic, including in groups with high severity of illness and high risk of multidrug-resistant (MDR) pathogens. Both the A-DROP and I-ROAD scores were useful in predicting the prognosis of NHCAP. Confirmation of intention to provide do not attempt resuscitation (DNAR) instructions was given to 333 patients (55.9%), and 313 patients agreed to DNAR instructions. CONCLUSIONS: NHCAP tends to occur in elderly patients with underlying diseases. The risk of MDR pathogens and the mortality rate are intermediate for community-acquired pneumonia and hospital-acquired pneumonia. As NHCAP is considered an important concept in an aging society, such as in Japan, establishing a treatment strategy that considers not only prognosis but also quality of life would be beneficial.

Nationwide surveillance of bacterial respiratory pathogens conducted by the surveillance committee of japanese society of chemotherapy, the japanese association for infectious diseases, and the japanese society for clinical microbiology in 2016: General view of the pathogens' antibacterial susceptibility.

The nationwide surveillance on antimicrobial susceptibility of bacterial respiratory pathogens from the patients in Japan was conducted by the Japanese Society of Chemotherapy, the Japanese Association for Infectious Diseases, and the Japanese Society for Clinical Microbiology in 2016. The isolates were collected from clinical specimens obtained from well-diagnosed adult patients with respiratory tract infections during the period between February 2016 and August 2016 by three societies. Antimicrobial susceptibility testing was conducted at the central reference laboratory according to the method recommended by Clinical Laboratory Standards Institute. Susceptibility testing was evaluated in 1062 strains (143 Staphylococcus aureus, 210 Streptococcus pneumoniae, 17 Streptococcus pyogenes, 248 Haemophilus influenzae, 151 Moraxella catarrhalis, 134 Klebsiella pneumoniae, and 159 Pseudomonas aeruginosa). Ratio of methicillin-resistant S. aureus was 48.3%, and those of penicillin-susceptible S. pneumoniae was 99.5%. Among H. influenzae, 14.1% of them were found to be ß-lactamase-producing ampicillin-resistant strains, and 41.1% to be ß-lactamase-non-producing ampicillin-resistant strains. Extended spectrum ß-lactamase-producing K. pneumoniae and multi-drug resistant P. aeruginosa with metallo ß-lactamase were 4.5% and 0.6%, respectively.

Efficacy of EGFR-TKIs with or without upfront brain radiotherapy for EGFR-mutant NSCLC patients with central nervous system metastases.

BACKGROUND: Although the clinical efficacy of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) in EGFR-mutant non-small cell lung cancer (NSCLC) patients has been demonstrated, their efficacy in EGFR-mutant NSCLCs with central nervous system (CNS) metastases and the role of radiotherapy remain unclear. This study aimed to determine if it is preferable to add upfront cranial radiotherapy to EGFR-TKIs in patients with EGFR-mutant NSCLC with newly diagnosed brain metastases. METHODS: We retrospectively analyzed the data of EGFR-mutant NSCLC patients with CNS metastases who received EGFR-TKIs as a first-line therapy. RESULTS: A total of 104 patients were enrolled and 39 patients received upfront brain radiotherapy, while 65 patients received first and second generation EGFR-TKIs first. The median time to treatment failure (TTF) was 7.8 months (95% confidence interval [CI]: 6.3-9.4). The median survival time (MST) was 24.0 months (95% CI: 20.1-30.1). The overall response rate of the CNS was 37%. The median CNS progression-free survival (PFS) was 13.2 months (95% CI: 10.0-16.2). Brain radiotherapy prior to EGFR-TKI prolonged TTF (11.2 vs. 6.8 months, P = 0.038) and tended to prolong CNS-PFS (15.6 vs. 11.1 months, P = 0.096) but was not significantly associated with overall survival (MST 26.1 vs. 24.0 months, P = 0.525). Univariate and multivariate analyses indicated that poor performance status and the presence of extracranial metastases were poor prognostic factors related to overall survival. CONCLUSION: EGFR-TKI showed a favorable effect for EGFR-mutant NSCLC patients with CNS metastases. Prolonged TTF and CNS-PFS were observed with upfront brain radiotherapy.

Nationwide surveillance of bacterial respiratory pathogens conducted by the surveillance committee of Japanese Society of Chemotherapy, the Japanese Association for Infectious Diseases, and the Japanese Society for clinical microbiology in 2014: General view of the pathogens' antibacterial susceptibility.

The nationwide surveillance on antimicrobial susceptibility of bacterial respiratory pathogens from the patients in Japan was conducted by Japanese Society of Chemotherapy, the Japanese Association for Infectious Diseases, and the Japanese Society for Clinical Microbiology in 2014. The isolates were collected from clinical specimens obtained from well-diagnosed adult patients with respiratory tract infections during the period between January 2014 and April 2015 by three societies. Antimicrobial susceptibility testing was conducted at the central reference laboratory according to the method recommended by Clinical Laboratory Standards Institute. Susceptibility testing was evaluated in 1534 strains (335 Staphylococcus aureus, 264 Streptococcus pneumoniae, 29 Streptococcus pyogenes, 281 Haemophilus influenzae, 164 Moraxella catarrhalis, 207 Klebsiella pneumoniae, and 254 Pseudomonas aeruginosa). Ratio of methicillin-resistant S. aureus was 43.6%, and those of penicillin-susceptible S. pneumoniae was 100%. Among H. influenzae, 8.2% of them were found to be ß-lactamase-producing ampicillin-resistant strains, and 49.1% to be ß-lactamase-non-producing ampicillin-resistant strains. Extended spectrum ß-lactamase-producing K. pneumoniae and multi-drug resistant P. aeruginosa with metallo ß-lactamase were 9.2% and 0.4%, respectively.

A Phase II Study of Irinotecan for Patients with Previously Treated Small-Cell Lung Cancer.

OBJECTIVE: Chemotherapy with irinotecan plus cisplatin has shown promise in chemo-naïve small-cell lung cancer (SCLC) patients. However, irinotecan treatment for relapsed or refractory SCLC has not been adequately evaluated. This phase II study evaluated the appropriate treatment schedule of irinotecan as a single agent. This study was designed to determine the antitumor activity, toxicity, and survival in previously treated SCLC patients. METHODS: Previously treated SCLC patients with at least one platinum-based regimen received irinotecan (100 mg/m2) on days 1 and 8, every 3 weeks, until disease progression. The assessment of the response rate was the primary endpoint. RESULTS: Thirty patients were enrolled, with an objective response rate of 41.3% (95% confidence interval [CI] 25.5-59.3), and a disease control rate of 69%. Median progression-free and overall survival was 4.1 months (95% CI, 2.2-5.4) and 10.4 months (95% CI, 8.1-14), respectively. The grade 3/4 hematological toxicities were neutropenia (36.7%), thrombocytopenia (3.3%), anemia (13.3%), and febrile neutropenia (6.6%). There were no grade 4 nonhematological toxicities. Frequent grade 3 nonhematological toxicities included diarrhea (10%), anorexia (6.6%), and hyponatremia (6.6%). CONCLUSIONS: This phase II study showed a high objective response rate and long survival. Irinotecan monotherapy schedule used was well tolerated, and could be an active treatment option for these patients.

Histological Transformation to Large Cell Neuroendocrine Carcinoma from Lung Adenocarcinoma Harboring an EGFR Mutation: An Autopsy Case Report.

We herein report a 58-year-old Japanese woman who survived 14 years after surgery for lung adenocarcinoma harboring an epidermal growth factor receptor (EGFR) exon 19 deletion. She developed recurrence, for which she underwent multimodal therapy, including EGFR-tyrosine kinase inhibitor (TKI) administration. She ultimately died from a rapidly progressive right lung tumor that was resistant to EGFR-TKI. According to the autopsy findings, she had combined large-cell neuroendocrine carcinoma (LCNEC) and adenocarcinoma in the right lung, which retained an EGFR exon 19 deletion in both components. Therefore, the histological transformation to LCNEC can be a mechanism of acquired EGFR-TKI resistance.

Nationwide surveillance of bacterial respiratory pathogens conducted by the surveillance committee of Japanese Society of Chemotherapy, the Japanese Association for Infectious Diseases, and the Japanese Society for Clinical Microbiology in 2012: General view of the pathogens' antibacterial susceptibility.

The nationwide surveillance on antimicrobial susceptibility of bacterial respiratory pathogens from the patients in Japan was conducted by Japanese Society of Chemotherapy, Japanese association for infectious diseases and Japanese society for Clinical Microbiology in 2012. The isolates were collected from clinical specimens obtained from well-diagnosed adult patients with respiratory tract infections during the period between January and December in 2012 by three societies. Antimicrobial susceptibility testing was conducted at the central reference laboratory according to the method recommended by Clinical Laboratory Standard Institutes. Susceptibility testing was evaluated in 1236 strains (232 Staphylococcus aureus, 225 Streptococcus pneumoniae, 16 Streptococcus pyogenes, 231 Haemophilus influenzae, 147 Moraxella catarrhalis, 167 Klebsiella pneumoniae and 218 Pseudomonas aeruginosa). Ratio of methicillin-resistant S. aureus was 51.3%, and those of penicillin-intermediate S. pneumoniae was 0.4%. Among H. influenzae, 5.6% of them were found to be ß-lactamase-producing ampicillin-resistant strains, and 37.2% to be ß-lactamase-non-producing ampicillin-resistant strains. Extended spectrum ß-lactamase-producing K. pneumoniae and multi-drug resistant P. aeruginosa with metallo ß-lactamase were 4.2% and 3.2%, respectively. Continuous national surveillance is important to determine the actual situation of the resistance shown by bacterial respiratory pathogens to antimicrobial agents.

A-DROP system for prognostication of NHCAP inpatients.

Nursing and healthcare-associated pneumonia (NHCAP) is a category of healthcare-associated pneumonia that was modified for the healthcare system of Japan. The NHCAP guidelines stated the difficulty in assessing the severity classifications, for instance, A-DROP. We compared the usefulness of different severity classifications (A-DROP, CURB-65, PSI, and I-ROAD) in predicting the prognosis of nursing and healthcare-associated pneumonia. We conducted a retrospective analysis on 303 adult patients hospitalized for nursing healthcare-associated pneumonia and community-acquired pneumonia, which were diagnosed at the Department of Respiratory Medicine of Niigata General City Hospital between January 2012 and December 2014. We evaluated 159 patients with community-acquired pneumonia and 144 with nursing and healthcare-associated pneumonia. In the nursing and healthcare-associated pneumonia group, 30-days mortality and in-hospital mortality rates were 6.5% and 8.7%, respectively, in severe cases and 16.1% and 25.0%, respectively, in the most severe cases, based on A-DROP. With I-ROAD, these rates were 11.1% and 11.1%, respectively, in group B and 14.9% and 20.7%, respectively, in group C. With PSI, the rates were 2.3% and 6.8%, respectively, in class IV and 14.3% and 19.8%, respectively, in class V. Despite some variability due to the small sample size, both the 30-days and in-hospital mortality rates increased as the severity increased. In this study, both the 30-days mortality and in-hospital mortality rates in the nursing and healthcare-associated pneumonia group tended to increase in severity with the A-DROP. We found that A-DROP was useful in predicting the prognosis of nursing and healthcare-associated pneumonia.

Pneumonia Severity Assessment Tools for Predicting Mortality in Patients with Healthcare-Associated Pneumonia: A Systematic Review and Meta-Analysis.

BACKGROUND: In contrast to community-acquired pneumonia (CAP), no specific severity assessment tools have been developed for healthcare-associated pneumonia (HCAP) in clinical practice. OBJECTIVES: In this review, we assessed the clinical significance of severity assessment tools for HCAP. METHODS: We identified related articles from the PubMed database. The eligibility criteria were original research articles evaluating severity scoring tools and reporting the outcomes of mortality in patients with HCAP. RESULTS: Eight articles were included in the meta-analysis. The PORT score and CURB-65 were evaluated in 7 and 8 studies, respectively. Using cutoff values of ≥IV and V for the PORT score, the diagnostic odds ratios (DORs) were 5.28 (2.49-11.17) and 3.76 (2.88-4.92), respectively, and the areas under the curve (AUCs) were 0.68 (0.64-0.72) and 0.71 (0.67-0.75), respectively. Conversely, the AUCs for ≥IV and V were 0.71 (0.67-0.76) and 0.74 (0.70-0.78), respectively, when applied only to nonimmunocompromised patients. In contrast, when using cutoff values of ≥2 and ≥3 for CURB-65, the DORs were 3.35 (2.26-4.97) and 2.65 (2.05-3.43), respectively, and the AUCs were 0.65 (0.61-0.69) and 0.66 (0.62-0.70), respectively. Conversely, the AUCs for ≥2 and ≥3 were 0.65 (0.61-0.69) and 0.68 (0.64-0.72), respectively, when applied only to nonimmunocompromised patients. CONCLUSIONS: The PORT score and CURB-65 do not have substantial power compared with the tools for CAP patients, although the PORT score is more useful than CURB-65 for predicting mortality in HCAP patients. According to our results, however, these tools, especially the PORT score, can be more useful when limited to nonimmunocompromised patients.

Sequential Granulocyte-Macrophage Colony-Stimulating Factor Inhalation after Whole-Lung Lavage for Pulmonary Alveolar Proteinosis. A Report of Five Intractable Cases.

Autoimmune pulmonary alveolar proteinosis (aPAP) is a rare disease characterized by the excessive accumulation of surfactant proteins within the alveolar spaces and by higher titers of autoantibodies to granulocyte-macrophage colony-stimulating factor (GM-CSF) in the serum and bronchoalveolar lavage fluid. The antibodies inhibit the maturation and phagocytosis of alveolar macrophages. Although the standard therapy for aPAP has been whole-lung lavage (WLL), this procedure is invasive and needs to be repeated for several years. GM-CSF inhalation therapy is a new procedure for treating aPAP and can induce remission with less invasiveness, although it is generally less effective in severe cases. We evaluated five cases with remarkable improvement by using sequential GM-CSF inhalation therapy after WLL; however, the treatment failed when this therapy preceded WLL. Therefore, sequential GM-CSF inhalation after WLL may reinforce the efficiency of WLL in patients with severe aPAP.

Prognostic implications of aspiration pneumonia in patients with community acquired pneumonia: A systematic review with meta-analysis.

Aspiration pneumonia is thought to be associated with a poor outcome in patients with community acquired pneumonia (CAP). However, there has been no systematic review regarding the impact of aspiration pneumonia on the outcomes in patients with CAP. This review was conducted using the MOOSE guidelines: Patients: patients defined CAP. EXPOSURE: aspiration pneumonia defined as pneumonia in patients who have aspiration risk. Comparison: confirmed pneumonia in patients who were not considered to be at high risk for oral aspiration. OUTCOMES: mortality, hospital readmission or recurrent pneumonia. Three investigators independently identified published cohort studies from PubMed, CENTRAL database, and EMBASE. Nineteen studies were included for this systematic review. Aspiration pneumonia increased in-hospital mortality (relative risk, 3.62; 95% CI, 2.65-4.96; P < 0.001, seven studies) and 30-day mortality (3.57; 2.18-5.86; P < 0.001, five studies). In contrast, aspiration pneumonia was associated with decreased ICU mortality (relative risk, 0.40; 95% CI, 0.26-0.60; P < 0.00001, four studies). Although there are insufficient data to perform a meta-analysis on long-term mortality, recurrent pneumonia, and hospital readmission, the few reported studies suggest that aspiration pneumonia is also associated with these poor outcomes. In conclusion, aspiration pneumonia was associated with both higher in-hospital and 30-day mortality in patients with CAP outside ICU settings.

Analysis of the influenza A (H1N1) 2009 pandemic infection in Japanese asthmatic patients: using a questionnaire-based survey.

BACKGROUND: Influenza infection is known to be an exacerbating factor in the control of asthma, therfore its prevention is critical in managing asthma. The aim of this study was to investigate the influenza A H1N1 2009 pandemic virus (H1N1 pdm09) infection in adult asthmatic patients. METHODS: Data were obtained from a questionnaire-based survey of asthmatic patients conducted from September to October 2010 in Niigata Prefecture. Patient background, H1N1 pdm09 infection, vaccination status, and asthma exacerbation due to influenza infection were analyzed. RESULTS: In total, 2,555 cases were analyzed. The incidence of the infection was 6.7% (95% confidence interval [CI]: 5.7-7.6), and the rate of vaccination was 63.9% (95% CI: 62.1-65.8). The odds ratio (OR) for vaccination against the infection among adult patients and younger patients (≤ the median age) were 0.61 (95% CI: 0.45-0.84) and 0.62 (95% CI: 0.42-0.90), respectively. However, OR among the older patient (> median age) were 1.38 (95%CI: 0.66-2.89). The rate of infection-induced asthma exacerbation was 23.2% (95% CI: 18.6-29.6), and the OR for vaccination against the infection-induced asthma exacerbation was 1.42 (95% CI: 0.69-2.92). CONCLUSIONS: The effectiveness of the vaccination against the H1N1 pdm09 virus was confirmed during the first pandemic season, but it was limited. Further investigation on H1N1 pdm09 virus infection in asthmatics will be required.

Nationwide surveillance of antimicrobial susceptibility patterns of pathogens isolated from surgical site infections (SSI) in Japan.

To investigate the trends of antimicrobial resistance in pathogens isolated from surgical site infections (SSI), a Japanese surveillance committee conducted the first nationwide survey. Seven main organisms were collected from SSI at 27 medical centers in 2010 and were shipped to a central laboratory for antimicrobial susceptibility testing. A total of 702 isolates from 586 patients with SSI were included. Staphylococcus aureus (20.4 %) and Enterococcus faecalis (19.5 %) were the most common isolates, followed by Pseudomonas aeruginosa (15.4 %) and Bacteroides fragilis group (15.4 %). Methicillin-resistant S. aureus among S. aureus was 72.0 %. Vancomycin MIC 2 µg/ml strains accounted for 9.7 %. In Escherichia coli, 11 of 95 strains produced extended-spectrum ß-lactamase (Klebsiella pneumoniae, 0/53 strains). Of E. coli strains, 8.4 % were resistant to ceftazidime (CAZ) and 26.3 % to ciprofloxacin (CPFX). No P. aeruginosa strains produced metallo-ß-lactamase. In P. aeruginosa, the resistance rates were 7.4 % to tazobactam/piperacillin (TAZ/PIPC), 10.2 % to imipenem (IPM), 2.8 % to meropenem, cefepime, and CPFX, and 0 % to gentamicin. In the B. fragilis group, the rates were 28.6 % to clindamycin, 5.7 % to cefmetazole, 2.9 % to TAZ/PIPC and IPM, and 0 % to metronidazole (Bacteroides thetaiotaomicron; 59.1, 36.4, 0, 0, 0 %). MIC90 of P. aeruginosa isolated 15 days or later after surgery rose in TAZ/PIPC, CAZ, IPM, and CPFX. In patients with American Society of Anesthesiologists (ASA) score ≥3, the resistance rates of P. aeruginosa to TAZ/PIPC and CAZ were higher than in patients with ASA ≤2. The data obtained in this study revealed the trend of the spread of resistance among common species that cause SSI. Timing of isolation from surgery and the patient's physical status affected the selection of resistant organisms.

The collagenolytic action of MMP-1 is regulated by the interaction between the catalytic domain and the hinge region.

The role of the hinge region in the unwinding and cleavage of type I collagen by interstitial collagenase (MMP-1) has been studied at 37 °C and pH 7.3. The collagenolytic processing by MMP-1 displays a very similar overall rate for both chains of collagen I, even though the affinity is higher for the α-1 chain and the cleavage rate is faster for the α-2 chain. MMP-1 binding to collagen I brings about a significant unwinding of the triple-helical arrangement only after the first cleavage step of the α-1 and α-2 chains. The proteolytic processing by wild-type MMP-1 on a synthetic substrate and collagen I has been compared with that observed for site-directed mutants obtained either by truncating the hinge region (∆255-272) or by individually replacing the conserved amino acids Val268, Gly272, and Lys277 of the hinge region with residues observed for the corresponding position in stromelysin-1 (MMP-3), a noncollagenolytic metalloproteinase. The ∆256-272 mutant has no collagenolytic activity, clearly demonstrating the crucial role of this region for the enzymatic processing of collagen I. However, among various mutants investigated, only Gly272Asp shows a dramatically reduced enzymatic activity both on the synthetic substrate and on collagen I. This effect, however, is clearly related to the substituting residue, since substitution of Ala or Asn for Gly272 does not have any effect on the kinetic properties of MMP-1. These data suggest that the substrate specificity of MMP-1 is dictated by the reciprocal structural relationships between the catalytic domain and the carboxy-terminal domain through the conformational arrangement of the hinge region.

Retrospective investigation of the clinical effects of tazobactam/piperacillin and sulbactam/ampicillin on aspiration pneumonia caused by Klebsiella pneumoniae.

Klebsiella pneumoniae is an important causative bacterium of aspiration pneumonia in many elderly patients. We retrospectively investigated the clinical effects of the early treatment of aspiration pneumonia and background factors in 24 patients from whom Klebsiella pneumoniae was isolated. Sulbactam/ampicillin (SBT/ABPC) was selected for early treatment in 12 of the 24 patients diagnosed with aspiration pneumonia, and tazobactam/piperacillin (TAZ/PIPC) was selected for the other patients. The effective rates and success rates of early treatment were significantly higher in the TAZ/PIPC group than in the SBT/ABPC group (p = 0.003 and 0.027, respectively). Although no significant difference was noted because of the limited number of cases, the survival rates after 30 days were 91.7 and 58.3 % in the TAZ/PIPC and SBT/ABPC groups, respectively. Several bacteria isolated with Klebsiella pneumoniae were resistant bacteria, such as methicillin-resistant Staphylococcus aureus or Pseudomonas aeruginosa, and no anaerobe or extended-spectrum ß-lactamase-producing Klebsiella pneumoniae was isolated. Thirteen and 11 of the 24 cases were classified as healthcare-associated pneumonia (HCAP) and hospital-acquired pneumonia (HAP), respectively, with no case classified as community-acquired pneumonia (CAP). As population aging progresses, the frequency of aspiration pneumonia classified as HCAP will increase. To cover anaerobes, it is necessary to select antibacterial drugs, such as TAZ/PIPC, for early treatment in consideration of resistant gram-negative bacteria to improve the outcome, and not drugs with weak activity against these bacteria.

Main bronchial diverticula in the subcarinal region: their relation to airflow limitations.

BACKGROUND: To date, bronchial diverticula have generally been treated as a pathological condition associated with chronic obstructive pulmonary disease (COPD), although only a limited amount of published information is available on the relationship between bronchial diverticula as depicted by multidetector computed tomography (MDCT) and airflow limitations. PURPOSE: To evaluate the relationship between airflow limitations and main bronchial diverticula in the subcarinal region using spirometry and thin-section MDCT. MATERIAL AND METHODS: A total of 189 consecutive adult patients were retrospectively evaluated based on spirometry and thin-section MDCT of the chest. All examinations were performed at our institution between June and October 2008. The study group included 70 women and 119 men with a mean age of 65 years (range 19-86 years). The relationship between the FEV(1)% and bronchial diverticula in the subcarinal region was analyzed (Student's t-test). RESULTS: The indications for conducting the examinations were pulmonary diseases (82 patients), cardiovascular diseases (22), extrapulmonary malignancies (74), and other conditions (11). A total of 84/189 (44.4%) patients showed bronchial diverticula, and the FEV(1)% of 70/84 (83.3%) patients was above 70. The FEV(1)% of patients with lesions ranged from 26.0 to 97.8 (mean 76.8), whereas the range was 28.1-94.4 (mean 73.7) in those without lesions. There was no significant association between the FEV(1)% and the presence of subcarinal bronchial diverticula (P > 0.05). CONCLUSION: Our data demonstrate that thin-section chest CT commonly demonstrates main bronchial diverticula in the subcarinal region in patients without airflow limitations. We propose that the presence of a small number of tiny bronchial diverticula under the carina may not be a criterion for the diagnosis of COPD.