Isolation of ESBL-producing Bacteria from Sputum in Community-acquired Pneumonia or Healthcare-associated Pneumonia Does Not Indicate the Need for Antibiotics with Activity against This Class

Abstract

Objective In the past decade, extended-spectrum β-lactamase (ESBL)-producing bacteria have increasingly frequently been isolated from various kinds of clinical specimens. However, the appropriate treatment of pneumonia in which ESBL-producing bacteria are isolated from sputum culture is poorly understood. To investigate whether or not ESBL-producing bacteria isolated from sputum in pneumonia cases should be treated as the causative bacteria. Methods and Patients In this retrospective study, we screened for patients, admitted between January 2009 and December 2015 in whom pneumonia was suspected and for whom sputum cultures yielded Escherichia coli or Klebsiella spp. isolates. We identified patients with community-acquired pneumonia (CAP) or healthcare-associated pneumonia (HCAP) from whom ESBL-producing bacteria had been isolated from sputum culture and to whom antibiotic treatment had been given with a diagnosis of pneumonia. We analyzed the patients' backgrounds and the effect of the antibiotic treatment for the initial 3-5 days. Results From 400 patients initially screened, 27 with ESBL-producing bacteria were secondarily screened. In this subset of patients, 15 were diagnosed with pneumonia, including 7 with CAP (5 E. coli and 2 K. pneumoniae) and 8 with HCAP (8 E. coli). These patients exhibited an average age of 84.1 years old, and 9 of 15 were men. No patients were initially treated with antimicrobials that are effective against isolated ESBL-producing bacteria. However, 13 of 15 patients showed improvement of pneumonia following the initial antibiotic treatment. Conclusion ESBL-producing bacteria isolated from sputum are not likely to be the actual causative organisms of pneumonia.

Utility of the Quick Sequential Organ Failure Assessment in Japanese patients with nursing‐ and healthcare‐associated pneumonia

“…Similar to a recent report, the present results showed no significant differences between pneumonia‐related mortality in patients with and without detection of PDR pathogens . Horie et al reported that antibiotics effective against ESBL‐producing bacteria were not always necessary when ESBL‐producing bacteria were cultured in sputum samples, and our previous study using the clone library method with bronchoalveolar lavage fluid also showed that detection of MRSA in cultures might not be associated with the need for treatment with anti‐MRSA medications . Therefore, physicians need to consider the importance of evaluating risk factors for detecting PDR pathogens and the detection of PDR pathogens in the treatment of pneumonia patients.…”

Healthcare-associated pneumonia: is there any reason to continue to utilize this label in 2019?

“…The recognition of risk factors for MRSA pneumonia might be of clinical help (Table 2). Similarly, one study showed that patients from whom ESBL-producing bacteria were cultured in sputum had favourable outcomes without coverage of these pathogens [51].…”

“…A study from Japan reported that the outcomes of 15 patients with pneumonia and ESBL-producing enterobacteria (five E. coli and two K. pneumoniae with CAP, eight E. coli with HCAP) were not affected by the failure to cover these pathogens [51].…”

To Use, or Not to Use Carbapenem When Extended-spectrum β-lactamase (ESBL)-producing Bacteria Are Isolated from Sputum Cultures, That Is the Question

“…In this issue of Internal Medicine, Horie et al reports that the seven community-acquired pneumonias (CAPs) and eight healthcare-associated pneumonias (HCAPs) with ESBL-producing bacteria isolated from sputum cultures were treated with antibiotics other than carbapenems and cephamycins ( 6 ). Thirteen patients (87%) successfully improved after days 3-5 with the initial antibiotics; only one had to change CTRX to MEPM.…”

“…Conventional culture methods cannot identify all of the lung bacteria that can be detected by molecular methods such as the metagenomic sequencing. In the study by Horie et al ( 6 ), they also detected microorganisms other than ESBL-producing bacteria by culture methods, but more bacteria, including causative bacteria, could exist. In the next era, we have to detect the microbiota in the lung and unravel the pathogenesis and the relationships among those populations.…”