Factors Associated with Extended-spectrum ß-lactamase-producing Enterobacteria Isolated from Respiratory Samples.

Objective Although extended-spectrum ß-lactamase (ESBL)-producing bacteria are a global threat, as they may cause respiratory infection, the factors associated with the isolation of these bacteria from sputum remain unclear. We therefore explored the factors related to ESBL-producing Klebsiella pneumoniae and Escherichia coli isolated from sputum samples. Methods This study included consecutive patients admitted to our department from 2010 to 2021 with K. pneumoniae or E. coli isolated from their sputum. The patients were categorized into ESBL-producing and non-ESBL-producing groups, and the factors associated with ESBL-producing bacteria isolation were assessed using a binomial logistic regression analysis. Results We included 82 patients, and ESBL-producing pathogens were isolated from 23 (28%). The usage rates of cephem [odds ratio (OR) 4.000, 95% confidence interval (CI) 1.402-11.409, p=0.010], quinolone (OR 2.961, 95% CI 1.097-7.996, p=0.032), and macrolide (OR 4.273, 95% CI 1.518-12.028, p=0.006) in the past year were significantly higher in the ESBL-producing group than in the non-ESBL-producing group. The multivariate analysis revealed that the applications of cephem (adjusted OR: 4.130, 95% CI: 1.233-13.830, p=0.021) and macrolide (adjusted OR: 6.365, 95% CI: 1.922-21.077, p=0.002) was independently associated with the isolation of ESBL-producing bacteria. Conclusion A history of cephem and macrolide use can be considered a risk factor for ESBL-producing bacteria isolation from sputum samples. Physicians need to consider these risk factors when determining antibiotics for the treatment of patients with respiratory infections.

Aspergillus Nodule in a Patient With Autoimmune Pulmonary Alveolar Proteinosis.

Although autoimmune pulmonary alveolar proteinosis (APAP) is more likely to be associated with infectious diseases, clinical case-based evidence is too limited to confirm this. We describe a case of a man in his late forties diagnosed with APAP nine years prior to the current presentation. A nodule in the right upper lobe gradually increased from 8 to 12 mm over a period of 6 months and was suspicious of malignancy. The pathological analyses revealed Aspergillus nodule without any malignant features. This study aims to report a case of Aspergillus nodule with APAP and discuss the differential diagnosis of solitary lung nodule developed in APAP.