Antimicrobial susceptibility of anaerobic bacteriaAntimicrobial susceptibility and clinical findings of significant anaerobic bacteria in southern Spain
Introduction
Anaerobic bacteria are common pathogens in humans. Although most clinically significant anaerobes are involved in mixed infections alongside aerobic bacteria, they can be responsible for severe disease in certain circumstances, such as in blood infections or when present in normally sterile body sites. Infections due to anaerobic isolates may sometimes be missed because of the special measures required for their transportation. Other critical factors for the successful isolation of these microorganisms in the microbiology laboratory include incubation in anaerobic atmosphere, the use of specialized culture media, and prolonged culture [1].
Antimicrobial susceptibility testing of anaerobic bacteria is performed by a minority of laboratories, including only 21% of laboratories in the USA [2,3], while only 19% of laboratories in Scotland routinely carry out anaerobe identification or antimicrobial susceptibility [4]. Current recommendations emphasize that antimicrobial susceptibility testing of anaerobic isolates is only needed for severe infections or for epidemiological studies [5,6], although a rise in the resistance of anaerobes to some antimicrobial agents may indicate a greater need for this testing [5].
Few data are available on the resistance of anaerobes worldwide, and the objective of this study was to report the percentage resistance of clinically significant anaerobes in a tertiary hospital in Southern Spain and the key clinical characteristics of these patients.
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Clinical features
This was a prospective study of microbiological data that were recorded in a file after obtaining the results, while the patient data were obtained from our Laboratory Information System (LIS).
Data were gathered on: age and sex, infection site, infection type (polymicrobial vs. monomicrobial), risk factors, underlying diseases, clinical manifestations, laboratory findings, treatment, and outcome. For Clostridioides difficile infection, information was also recorded on recurrence, ribotype,
Clinical characteristics of patients
The study included 243 patients, 51% (n = 124) males, with a mean age of 54.3 years (1-94). Table 1, Table 2 exhibit their clinical characteristics. Samples were from abdominal abscesses (32%, n = 78), stool samples (C. difficile) (18.1%; n = 44), skin and soft tissues (17.6%, n = 43), and urogenital sites (10.6%, n = 26), among others (Table 3).
Isolated bacteria
The study included 276 non-repetitive clinically relevant anaerobic strains: 53.8% (n = 125) were Gram-negative bacilli, with 29.7% (n = 82) being
Discussion
This surveillance study established the antimicrobial susceptibility of 276 clinically relevant anaerobic bacteria isolated in the routine testing of samples from patients in a tertiary-care hospital in Southeast Spain. The bacteria belonged to all major genera of anaerobes isolated from patients with different types of infection, localized in the abdomen in the majority of cases and accompanied by pain and fever. Blood test markers, especially C-reactive protein levels, were elevated in 136
Conflict of interest
Authors declare no conflict of interest.
Funding
None.
References (28)
Anaerobic infections in humans: an overview
Anaerobe
(1995)- et al.
National hospital survey of anaerobic culture and susceptibility methods: III
Anaerobe
(2008) - et al.
Resistance trends in antimicrobial susceptibility of anaerobic bacteria, part I
Clin. Microbiol. Newsl.
(2011) - et al.
Infected breast cyst due to Prevotella buccae resistant to metronidazole
Anaerobe
(2017) - et al.
Breast abscess due to Finegoldia magna in a non-puerperal woman
Anaerobe
(2017) - et al.
Peritoneal infection due to Peptoniphilus harei in a patient with intestinal occlusion
Anaerobe
(2017) - et al.
Recent evolution of antibiotic resistance in the anaerobes as compared to previous decades
Anaerobe
(2015) - et al.
Changes in the antibiotic susceptibility of anaerobic bacteria from 2007-2009 to 2010-2012 based on the CLSI methodology
Anaerobe
(2016) - et al.
Evaluation of the routine antimicrobial susceptibility testing results of clinically significant anaerobic bacteria in a Slovenian tertiary-care hospital in 2015
Anaerobe
(2017) - et al.
Antibiotic susceptibility profiles of anaerobic pathogens in The Netherlands
Anaerobe
(2015)
Antimicrobial susceptibility of clinically isolated anaerobic bacteria in a University hospital Centre Split, Croatia in 2013
Anaerobe
Metronidazole resistance and nim genes in anaerobes: a review
Anaerobe
Evaluation of antibiotic susceptibility of Bacteroides, Prevotella and Fusobacterium species isolated from patients of the N.N. Blokhin cancer research center, Moscow, Russia
Anaerobe
Clostridium innocuum is a vancomycin-resistant pathogen that may cause antibiotic-associated diarrhea
Clin. Microbiol. Infect.
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