Factors associated with acid-fast bacillus isolation in patients with noncystic fibrosis bronchiectasis: A cross-sectional study.

INTRODUCTION: Acid-fast bacillus (AFB) is a major pathogen that causes noncystic fibrosis bronchiectasis requiring multidrug chemotherapy. Bronchoscopic bronchial wash is performed to determine the causative pathogens of bronchiectasis; but, predictive factors for AFB isolation have not been fully elucidated. This study aimed to determine the factors associated with AFB isolation from bronchial wash samples. METHODS: This was a single-center, cross-sectional study. Patients undergoing bronchoscopic bronchial wash for bronchiectasis were included, whereas those who did not undergo high-resolution computed tomography (HRCT); had acute pneumonia, interstitial lung disease, and a positive polymerase chain reaction result but a negative culture result for AFB; or in whom a guide sheath was used for suspected lung cancer were excluded. Binomial logistic regression was used to analyze the factors associated with a positive culture for AFB. RESULTS: Of the 96 included cases, AFB isolation was observed in the bronchial wash fluid of 26 patients (27%). No smoking history, a positive result for antiglycopeptidolipid (GPL)-core IgA antibody, and the presence of tree-in-bud appearance, multiple granular and nodular images on HRCT were more commonly observed in patients with AFB isolation than in those without. In the multivariate analysis, the tree-in-bud appearance (odds ratio, 4.223; 95% CI, 1.046-17.052) and anti-GPL core IgA antibody (odds ratio, 9.443; 95% CI, 2.206-40.421) were significantly associated with AFB isolation. CONCLUSIONS: The tree-in-bud appearance on HRCT is likely to predict AFB isolation independent of anti-GPL core IgA antibody results. Bronchoscopic bronchial wash should be recommended for bronchiectasis with multiple granulomas on HRCT.

Risk factors for disease-related deterioration following diagnostic bronchoalveolar lavage procedures in diffuse lung disease: a case-control study.

BACKGROUND: Although the risk factors for diagnostic bronchoalveolar lavage (BAL)-induced acute exacerbations in patients with idiopathic pulmonary fibrosis (IPF) have been previously reported, no study has assessed these in patients with non-IPF. We aimed to identify the risk factors for BAL-induced disease deterioration (BAL-DD) in all types of diffuse lung disease. METHODS: Patients with diffuse lung disease who underwent BAL at our hospital from April 2012 to November 2017 were retrospectively analyzed. The patient information, laboratory data, radiological findings, and BAL fluid analysis results in patients who developed BAL-DDs were compared with those in patients who did not. RESULTS: BAL-DDs occurred in 14 (3.3%) of the 429 patients included the study. The BAL-DD group had a significantly poorer performance status, higher C-reactive protein level, lower partial pressure of oxygen in the arterial blood at rest, greater proportion of desaturation on exertion and cases having followed a progressive clinical course before BAL, and more extensive consolidation and ground-glass opacity on chest high-resolution computed tomography (HRCT) than the non-BAL-DD group. A high total cell concentration and an increased number of eosinophils in the BAL fluid were more frequently found in patients with BAL-DD than in those without. CONCLUSIONS: Patients with decreased physical activity level, increased level of inflammatory markers, low oxygenation status, and extensive lung involvements on chest HRCT and following a progressive clinical course before BAL may be warned of the BAL-DD risk. Elevated eosinophil counts in the BAL fluid could be associated with the triggering of BAL-DDs.

A case report of primary sternal osteomyelitis caused by polymicrobial bacteria, including Actinomyces israelii.

We herein report a case of primary sternal osteomyelitis caused by polymicrobial bacteria, including Actinomyces israelii. A 72-year-old man presented with a fever and precordial pain. Chest computed tomography (CT) revealed peristernal fluid associated with an osteolytic lesion and a peripheral nodule in the right upper lobe. We suspected sternal osteomyelitis, and an incision and drainage were performed. Culture of the drainage fluid and bone tissue yielded A. israelii, Fusobacterium necrophorum, and Streptococcus constellatus. Treatment with benzylpenicillin potassium (PCG) was administered. A subsequent chest CT scan showed that the peripheral nodule decreased in size after antimicrobial therapy. We therefore presumed the peripheral nodule as septic pulmonary embolism(SPE). Antimicrobial agents were administered for a total of 6 months. To our knowledge, this is the first case report of primary sternal osteomyelitis associated with presumed SPE caused by polymicrobial bacteria, including A. israelii. It is important to identify the causative pathogen in osteomyelitis, which requires long-term antibiotic treatment.

In vitro and in vivo potency of polymyxin B against IMP-type metallo-beta-lactamase-producing Pseudomonas aeruginosa.

Multidrug-resistant Pseudomonas aeruginosa, especially metallo-beta-lactamase (MBL)-producing P. aeruginosa, is an important pathogen in nosocomial infection and emergence of this pathogen has revived interest in polymyxin B (PMB) and colistin (COL). In this study, we evaluated the efficacies of PMB, COL and other antipseudomonal agents against IMP-type MBL-producing P. aeruginosa both in vitro and in vivo. A total of 75 isolates of bla(IMP)-positive P. aeruginosa obtained from clinical specimens (94.6% of isolates demonstrated resistance to beta-lactam, fluoroquinolone and aminoglycoside agents) were evaluated in the in vitro study. More than 90% of the examined isolates were susceptible to PMB (minimum inhibitory concentration for 50/90% of the isolates (MIC(50)/MIC(90)) 4/4 mg/L), although COL was less potent (MIC(50)/MIC(90) 8/16 mg/L). Cyclophosphamide-treated mice were intraperitoneally inoculated with bla(IMP)-positive P. aeruginosa. Treatment with PMB, but not COL, imipenem/cilastatin or aztreonam, significantly improved the survival rate and decreased the number of bacteria in the blood in a dose-dependent manner. Our results indicate that, among the agents studied, PMB is the most effective agent against bla(IMP)-positive P. aeruginosa.