1. bookVolume 61 (2022): Issue 1 (March 2022)
Journal Details
License
Format
Journal
eISSN
2545-3149
First Published
01 Mar 1961
Publication timeframe
4 times per year
Languages
English, Polish
Open Access

The Role of the Bacteroides spp. in Bacteraemia

Published Online: 31 Mar 2022
Volume & Issue: Volume 61 (2022) - Issue 1 (March 2022)
Page range: 13 - 20
Received: 01 Feb 2022
Journal Details
License
Format
Journal
eISSN
2545-3149
First Published
01 Mar 1961
Publication timeframe
4 times per year
Languages
English, Polish
Introduction

Anaerobic bacteria are clinically significant pathogens in blood stream infections and septicaemia [15]. It is estimated that the consequence of bacteraemia of this aetiology has a high mortality rate of 16–27% [9, 28, 37, 41, 57, 62, 68]. Mortality is even higher when it comes to patients with antimicrobial empirical treatment not covering anaerobes – then the mortality rate increases to 45% [7, 37] or even to 63% [70]. Bacteroides/Parabacteroides anaerobic Gram-negative bacilli are the most commonly identified anaerobic bacteria causing bacteraemia and account for 1,2–13,7% of all positive blood samples from hospitalized patients [11, 13, 18, 28, 29, 62].

Anaerobic infections including bacteraemia nearly always arise from contamination by endogenous bacteria into contiguous or other sites. The most common sources of bacteraemia caused by anaerobes are: gastrointestinal tract, female genitourinary tract, abscesses and wound-/skin- and soft tissues and lower respiratory tract infections [14]. Postoperative gastrointestinal tract and genitourinary system patients and those with malignant tumours are at higher risk of bacteraemia caused by anaerobes [9, 57, 68]. Clinical significance of Bacteroides spp. bacilli is caused by the occurrence of numerous factors of virulence and increasing antibiotic resistance [69]. In the past decade the number of multidrug resistant isolates from the Bacteroides/Parabacteroides spp. has increased [11, 18, 36].

The genus Bacteroides

Among all species of genus Bacteroides, phenotypically similar species were identified to the Bacteroides fragilis group (BFG). This group consists of species of significant clinical importance: Bacteroides caccae, B. eggerthii, B. fragilis, B. nordii, B. ovatus, B. salyersiae, B. stercoris, B. thetaiotaomicron, B. uniformis, B. vulgatus. Within BFG, the number of newly-recognized species is increasing and several members have been renamed to Parabacteroides group. They are the dominant component of the flora of the gastrointestinal tract and are also present on the genital tract and in the upper respiratory tract [20, 54, 66].

BFG is found in approximately 50% of all bacteraemia caused by anaerobes. One study shows that BFG was detected in 46.6% of all episodes, among which B. fragilis were responsible for 54.4% and B. thetaiotaomicron – 22% of the infections [11]. Similar results, with a significant dominance of B. fragilis, are presented by other researchers [24, 28, 34, 57, 60].

Bacteria of the genus Bacteroides have numerous virulence factors, with the adhesins among them, which are responsible for adhering to tissues [65]. Polysaccharide envelope protects the bacteria from the immune response of the host, both cellular and humoral. It is also responsible for initiating the formation of abscesses, which are an essential element of BFG-induced infections. Untreated abscesses can grow and cause intestinal obstruction, erosion of blood vessels or fistula formation, depending on location. Abscesses can break and cause scattered infections and bacteraemia. The envelope also performs an important function in the adhesion of bacteria to the host cells and tissues. Additionally these bacteria produce a variety of enzymes that mediate tissue destruction: neuraminidase, protease, collagenase, hyaluronidase or chondroitinsulfatase. As a result of metabolic processes, Bacteroides strains produce short-chain fatty acids, mainly succinic acid, which protect them from phagocytosis by inhibiting granulocyte chemotaxis. Like all Gram-negative bacteria, Bacteroides contain lipopolysaccharide (LPS) a component of outer membrane cell. But the biologic activity of this endotoxin is 100 to 1000 times lower than that of LPS from Enterobacterales. The LPS of B. fragilis contains a lipid A moiety, but there are structural and chemical composition differences that render this LPS less potent than the LPS of Escherichia coli. The inability of B. fragilis LPS to activate TLR2 may be responsible for this difference. A large number of anaerobic bacteria, including B. fragilis can tolerate exposure to oxygen but do not replicate in atmospheric oxygen. The ability to survive exposure to oxygen is a different type of factor that facilitates the survival and thus pathogenicity of the organism [27, 39, 43, 65, 69].

Risk factors of anaerobic bacteraemia

Factors leading to anaerobic bacteraemia are mainly surgical procedures, crush injuries, the presence of foreign bodies, tissue necrosis, tumours, diabetes. In some cases, such as gastrointestinal perforation or aspiration pneumonia, sterile sites are exposed to large bacterial inoculum, which increases the chances of infection [62]. Finegold et al. [14] analysed 855 episodes of bacteraemia involving anaerobic microorganisms and identified abdominal cavity (52%), female genital tract (20%), lower respiratory tract (6%), upper respiratory tract (5%), and soft tissue infections (8%) as the main sources of disease [23]. The data presented by Tan et al. [57] are similar: abdominal infections (43%), followed by soft tissue infections (36%) and respiratory infections (5.5%) as a source of bacteraemia.

Other factors predisposing to anaerobic bacteraemia are: malignant tumours, haematological disorders, organ transplantation, alcoholism, drug addiction, immunosuppression, cytostatic therapy and corticosteroids [5, 11, 61]. Dumont et al. [11] analysed blood samples over a period of several months. Anaerobic aetiology has been shown in 5.8% of all cases of bacteraemia, most commonly in patients in abdominal and haematological surgery departments. In transplant departments in one of clinical hospitals in Warsaw, anaerobic bacteria were isolated from blood samples in 6.2% of cases of bacteraemia during the three-year follow-up period [25].

The elderly with comorbidities are definitely at higher risk of infection. Tan et al. [57] reported that 84% of anaerobic bacteraemia cases occurred in people over 60 years of age and the average age of affected patients was 73 years. Anaerobic bacteraemia mainly affects adults, with elderly patients over 65 years having high risk for developing bacteraemia. In contrast the prevalence of anaerobes in bloodstream infections in children is extremely rare with children between 2 and 6 years of age having the least risk ranging 0–0.5% overall [15]. An important aspect of anaerobe bacteraemia in children is that anaerobes frequently are present in cases of polymicrobial bacteraemia reflecting the fact that localized anaerobic infections are usually poly-microbial [5]. The importance of anaerobic bacteria in neonatal bacteraemia and sepsis is a relatively new phenomenon. The incidence of recovery of anaerobes in neonatal bacteraemia varies between 1.8% and 12.5%. The majority of cases reported in the literature were due to Bacteroides spp. (41%) other cultured anaerobes belonged to Clostridium spp. (32%), Peptostreptococcus spp. (20%) [5]. Risk factors of anaerobic blood infections in new-borns are as following: prolonged birth, premature rupture of foetal membranes, premature birth and respiratory failure [4, 15]. Aerobic-anaerobic blood culture pairs are suggested as a routine in neonatal practice [32].

Infections caused by anaerobic bacteria may be facilitated by the use of antibacterial agents to which those organisms are naturally resistant, such as aminoglycosides, aztreonam, phosphomycin, trimethoprim and 1st and 2nd generation fluoroquinolones (ciprofloxacin, levofloxacin) [6]. Nguyen et al. [37] demonstrated that the onset of highly resistant anaerobes infections correlates significantly with the previous treatment with beta-lactam antibiotics such as piperacillin, cefoxitin and cefotetan.

Microbiological diagnosis of anaerobic bacteraemia

Clinical characteristics of anaerobic bloodstream infections do not differ from bacteraemia caused by aerobic pathogens, but due to their longer generation time and rigorous growth requirements, it usually takes longer to establish the aetiology of infection [15]. In addition to identifying the pathogen present in the blood, the diagnosis should include the detection of the primary source of infection. Anaerobic bacteraemia carries a risk of developing systemic inflammatory response syndrome (SIRS), which presents with fever, tachycardia, tachypnoea, leukocytosis or leukopenia with neutrophilia [14, 62].

Blood cultures remain the gold standard for detection of the etiologic both anaerobes and aerobes agent of bloodstream infection. Blood culture for anaerobic bacteria is routinely carried out in all adult patients and in paediatric patients who have or are suspected of having such infection. Some authors suggest that anaerobic blood cultures should only be used selectively, if anamnestic data or clinical signs and symptom are suggestive of anaerobic bacteraemia. The opposite argument for this proceeding is the fact that routine use of anaerobic blood cultures gives opportunity of quick and effective culture of facultative anaerobes [15].

Blood samples collected to blood culture medium is cultivated on continuously monitored automated blood culture systems. Advances in contemporary blood culture media include use of resin-based media that absorb antibiotics and other inhibitory substances in the specimen to increase the detection rate. Additional advances to promote faster time to positivity include automation of workflow steps including loading bottles and measurement of blood volume, optimalization of temperature stabilization within the instrument. Contemporary systems of blood culture are as follows: BacT/Alert Virtuo (bioMérieux, France), BD Bactec FX (Becton, Dickinson and Company, Franklin Lakes, NJ), Versa Trek (Thermo Fisher Scientific, Wltham, MA). Routinely blood is collected to two bottles: an aerobic one allowing preferential growth of aerobic and facultative anaerobic microorganisms, and an anaerobic one allowing preferential growth of strict and facultative anaerobic bacteria [18, 67].

Previously, the identification of strict anaerobes in positive blood culture and other clinical samples mainly relied on in-house, classical biochemical testing, biochemical strips e.g. API ID 32A Kit, Rapid ID ANA II Systems or automated systems e.g. VITEK ANC Card and gas-liquid chromatography. These methods were available in only a few diagnostics laboratories and provided identification results only 48–72 hours later, mostly on the genus level. Introduction of novel technological modalities, most importantly MALDI-TOF MS (matrix-assisted laser desorption/ionization-time of flight mass spectrometry) and 16S rRNA sequencing, into the routine diagnostics workflow sped up and modernized diagnostics of anaerobes. Continuous developments in improving and complementing databases of bacterial spectra for MALDI-TOF MS analysis enables detection of rarely occurring or taxonomically close microorganisms. As a result of these developments several “new” or so far unknown anaerobic species have been described as causative agents in bacteraemia e.g. Solobacterium moorei, Actinotigum schaalii [15].

In vitro susceptibility tests are usually not done by clinical laboratories for anaerobes because of technically difficulties and the length of examination time to have impact on antibiotic decisions. However, resistance patterns of many anaerobes have changed significantly over the last decades. It forced some clinical laboratories to perform anaerobic susceptibility testing. International guidelines suggest that susceptibility testing of anaerobes is indicated for isolates from blood and other normally sterile body sites for e.g.: brain abscess, endocarditis, osteomyelitis, join infection and vascular graft. Susceptibility testing is obligatory in case of isolation of highly virulent strains or strains which have unpredictable susceptibility patterns. By 2021 routinely used method of determination antibiotic susceptibility of anaerobes was minimal inhibitory concentration (MIC) performed by standardized gradient strips (E-test) or agar and broth microdilution methods used by reference laboratories [20, 35]. Testing by gradient strips is relatively simple but costly. Recently, a standardized disc diffusion method for the susceptibility testing of Bacteroides spp. and other 4 important anaerobic species and genera has been compiled and published by EUCAST in EUCAST Clinical Breakpoint Tables v. 12.0. The present recommendation do not split anaerobes on Gram positive and Gram negative but determines clinical breakpoints in species-specific way. The most critical factor for this method is the time of incubation which cannot exceed 18+/−2 h [12].

What is worth noticing, anaerobic bacteria from blood samples do not always grow in monoculture. Tan et al. [57] reports that 57% of anaerobic bacteraemia were caused by a combination of microbes. Most frequently, other anaerobes (29%) and Enterobacterales bacilli (25%) were isolated. Other researchers report that in about 13–38% of cases, aerobic microorganisms were also present [11, 24, 28, 36, 57, 62].

Treatment of anaerobic bacteraemia

Carbenicillin, piperacillin, and ticarcillin are generally active against anaerobes but are considered suboptimal for infections involving B. fragilis. The β-lactam/β-lactamase inhibitor combination class of antibiotics still remains very active against B. fragilis. An exception is P. distasonis which is resistant to ampicillin/sulbactam [56]. Carbapenems have very good activity against BFG and other anaerobes. Tigecycline and tetracycline antibiotics are slightly less active than carbapenems and the β-lactam/β-lactamase inhibitor agents against B. fragilis [46].

Clindamycin was once a preferred antimicrobial agent for anaerobic infections including B. fragilis bacteraemia, but resistance has emerged with some B. fragilis strains. According to Sanford Guide clindamycin is a non-recommended agent, as resistance is likely to be present [46]. The same situation refers to moxifloxacin which was previously the preferred agent in the fluoroquinolone class for infections involving BFG. Recently resistance rates of 57 % to B. fragilis have been reported [55]. As for the fluoroquinolone only delafloxacin is active against BFG [46]. Metronidazole continue to be the most active agents against BFG [56].

Therefore, metronidazole, carbapenems and β-lactam/β-lactamase inhibitor combinations are still recommended to empirical therapy of anaerobic infections [55]

Antibiotic selection in anaerobic infections including bacteraemia is generally made empirically based on susceptibility test results from sentinel laboratories or literature reports. Empirical therapy in these infections depends on the clinical condition of the patient and the location of potential primary infection. When the source of bacteraemia is an extravascular site, surgical intervention and drainage are necessary to prevent the continuance of bacteraemia and to reduce the time of therapy. The location also depends on the duration of treatment, ranging from 10 days to 3 months. Knowledge of the antibiotic sensitivity profiles of anaerobic infections in individual hospitals/wards may be crucial in the choice of empirical therapy. Tan et al. [57] describe that the most commonly used empirical antibiotic therapy in Bacteroides bacteraemia were β-lactam with β-lactam inhibitor (amoxicillin/clavulanic acid or piperacillin/tazobactam) (44%), metronidazole (10%) and carbapenems (8.8%). Treatment of the majority of patients (72.65%) started with an appropriate initial antibiotic therapy. Sixteen percent of patients received antibiotics without anti-anaerobic activity.

Nguyen et al. [37] conducted a prospective observational study of 128 cases of bacteraemia involving BFG and presented that, in view of the increasing antibiotic resistance in these microbes. The conclusion of the study points that antibiotics traditionally used in empirical treatment, such as piperacillin with tazobactam or metronidazole, may be proven ineffective. They presented that clinical failure and mortality were more common in patients who did not receive a properly selected antibacterial agent.

Development of resistance to recognised antimicrobial agents in strains of Bacteroides spp.

The problem of antibiotic resistance, which is on the rise also among anaerobes, is particularly pronounced in BFG and makes it difficult to choose a reliable empirical therapy. Although ineffectiveness of metronidazole against Bacteroides spp. bacilli is rare, cases of resistance are reported increasingly. Essentially, non-prudent use of metronidazole can be held responsible for this phenomenon. One of the mechanisms of resistance is the production of 5-nitroimidazole nitroreductases, encoded by genes nim, which can be present in a “silent genes” form, which may not undergo expression [1, 3, 10, 31].

Clindamycin resistance of Bacteroides spp. is mainly associated with the production of adenyl-N-methyltransferase 23S rRNA, encoded by erm genes. The proportion of clindamycin-resistant strains has steadily increased over the past few decades [26, 33, 45, 47, 65].

As regards resistance to β-lactam antibiotics, the production of different classes of β-lactamases (cephalosporinase, carbapenemase) is of the greatest importance. The β-lactamase most commonly found in Bacteroides spp. is CepA (Cephalosporinase of class A), encoded by the chromosomal cep gene, and CfxA cephamycinase (Cefoxitin resistance class A), a product of the cfxA gene [40, 52]. Sometimes the bacilli produce CfiA carbapenemase encoded by the cfiA gene [16, 44, 52, 58], but not all strains with the cfiA gene are resistant to carbapenems. Similarly to the nim genes, those are also “silent” and are not always expressed. Resistance to β-lactam antibiotics may also be associated with a decrease in the permeability of these drugs through the outer membrane, as well as changes in the qualitative and quantitative composition of penicillin-binding proteins (PBPs) [47, 53]. Some authors suggest that when choosing carbapenems for empirical treatment, imipenem should be preferred, as its MICs were lower than MIC of doripenem and meropenem [22, 50].

Infections caused by multidrug-resistant (MDR) strains of Bacteroides spp. are still rare, but can cause serious therapeutic problems and are often fatal. The definition of MDR strains refers to aerobic bacteria resistant to at least three antibiotics from different groups. This condition may lead to overuse of this term when referring to anaerobes because Bacteroides isolates are often resistant to antibiotics from several groups, e.g. moxifloxacin, clindamycin and various beta-lactams. As Dumont et al. [11] suggest, the criteria for MDR for bacteria of the genus Bacteroides should be established with a distinction between less (e.g. to moxifloxacin, clindamycin) and greater resistance (to metronidazole, carbapenems). The literature describes cases of MDR infections [21]. The first publication on the MDR strain of B. fragilis dates back to 1995 from the United Kingdom (a patient with complications after gynaecological surgery) [59]. Since then, many researchers have described cases of bacteraemia caused by MDR-Bacteroides with different phenotypes and genotypes of antibiotic resistance. Most of the cases involved primary infections in the abdominal cavity, e.g. pancreatitis [64], a condition after gastric resection [23] or colorectal cancer [2, 8, 19, 49].

Ogane et al. [38] presented the antimicrobial susceptibility of 50 isolates of B. fragilis originated from blood samples from patients hospitalized in two hospitals in Japan between 2014 and 2019. Isolates were more sensitive to piperacillin with tazobactam (94% susceptible) than ampicillin/sulbactam (70% susceptible). Ninety six percent of isolates were sensitive to imipenem, while 90% were sensitive to meropenem and doripenem.

In Dumont et al. [11], BFG isolates were sensitive to piperacillin with tazobactam (97%), amoxicillin with clavulanic acid (92.5%) and imipenem (98.5%). According to the published studies sensitivity to clindamycin and moxifloxacin is significantly rare and occurs in 68% and 64% of isolates [38] and in 50.8% and 58.2% [11] respectively. Similar results are presented by other researchers [30, 57, 63]. Increasing resistance to clindamycin is observed in Europe [17, 42] including Poland [26]. The results were confirmed in study covering 8 medical centres. In the study 1957 isolates collected for 4 years (2008–9) were analysed. Resistance rates ranging 60% have been found for clindamycin and even higher above 80% to moxifloxacin, resistance for tigecycline was on the level 5.4%. For carbapenems, resistance of B. fragilis was 1.1–2.5%. B. fragilis isolate resistant to all antibiotics, with the exception of metronidazole, was also identified [57]. It was shown in one study, that among 67 Bacteroides spp. isolates only one, B. fragilis was resistant to metronidazole (1.5%) [11] and in a pool of 116 isolates also one, Parabacteroides distasonis, was resistant to metronidazole (1%). Alarming reports come from Pakistan including metronidazole resistance rate of 17.5% d [48].

To sum up, carbapenems and metronidazole should be considered the most active drugs to be used in the empirical therapy of anaerobic bacteraemia. The importance of the problem of strain resistance into these two antibiotics is even greater since the occurrence of such resistance is particularly related to the outcome of treatment and mortality in anaerobic bacteraemia [51]. Therefore, the collection of epidemiological data at local and global level, before treating patients with bacteraemia, can play an important role not only in public health but also in improving treatment outcomes [37].

Summary

Anaerobic bacteria remain an important cause of blood infections, mainly when it comes to elderly people with comorbidities. Most of them are caused by Gram-negative bacilli of the Bacteroides genus, which are a part of the natural human microflora. The increasing resistance to antibiotics among anaerobic bacteria prompts monitoring of the drug sensitivity profile in individual hospitals and wards. The development of MDR is worrying as it also affects broad-spectrum antibiotics. Therefore, in the case of bacteraemia, the determination of drug sensitivity should be a necessity. Rapid microbial diagnosis, targeted therapy and surgical treatment of a possible source of infection are crucial for prognosis improvement.

Alauzet C., Lozniewski A., Marchandin H.: Metronidazole resistance and nim genes in anaerobes: A review. Anaerobe, 55, 40–53 (2019) AlauzetC. LozniewskiA. MarchandinH. Metronidazole resistance and nim genes in anaerobes: A review Anaerobe 55 40 53 2019 10.1016/j.anaerobe.2018.10.00430316817 Search in Google Scholar

Ank N., Sydenham T.V., Iversen L.H., Justesen U.S., Wang M.: Characterisation of a multidrug-resistant Bacteroides fragilis isolate recovered from blood of a patient in Denmark using whole-genome sequencing. Int. J. Antimicrob. Agents, 46, 117–120 (2015) AnkN. SydenhamT.V. IversenL.H. JustesenU.S. WangM. Characterisation of a multidrug-resistant Bacteroides fragilis isolate recovered from blood of a patient in Denmark using whole-genome sequencing Int. J. Antimicrob. Agents 46 117 120 2015 10.1016/j.ijantimicag.2015.02.02425940770 Search in Google Scholar

Baaity Z., Jamal W., Rotimi V.O., Burián K., Leitsch D., Somogyvári F., Nagy E., Sóki J. Molecular characterization of metronidazole resistant Bacteroides strains from Kuwait. Anaerobe, doi: 10.1016/j.anaerobe.2021.102357 (2021) BaaityZ. JamalW. RotimiV.O. BuriánK. LeitschD. SomogyváriF. NagyE. SókiJ. Molecular characterization of metronidazole resistant Bacteroides strains from Kuwait Anaerobe 10.1016/j.anaerobe.2021.102357 2021 33713801 Open DOISearch in Google Scholar

Brook I.: Bacteraemia due to anaerobic bacteria in newborns. J. Perinatol. 10, 351–356 (1991) BrookI. Bacteraemia due to anaerobic bacteria in newborns J. Perinatol. 10 351 356 1991 Search in Google Scholar

Brook I.: The role of anaerobic bacteria in bacteraemia. Anaerobe, 16, 183–189 (2010) BrookI. The role of anaerobic bacteria in bacteraemia Anaerobe 16 183 189 2010 10.1016/j.anaerobe.2009.12.00120025984 Search in Google Scholar

Brook I.: Spectrum and treatment of anaerobic infections. J. Infect. Chemother. 22, 1–13 (2016) BrookI. Spectrum and treatment of anaerobic infections J. Infect. Chemother. 22 1 13 2016 10.1016/j.jiac.2015.10.01026620376 Search in Google Scholar

Brook I., Wexler H.M., Goldstein E.J.C.: Antianaerobic Antimicrobials: Spectrum and Susceptibility Testing. Clin. Microbiol. Rev. 26, 526–546 (2013) BrookI. WexlerH.M. GoldsteinE.J.C. Antianaerobic Antimicrobials: Spectrum and Susceptibility Testing Clin. Microbiol. Rev. 26 526 546 2013 10.1128/CMR.00086-12371949623824372 Search in Google Scholar

Centers for Disease Control and Prevention (CDC): Multidrug-resistant Bacteroides fragilis-Seattle, Washington, 2013. MMWR. Morb. Mortal. Wkly. Rep. 62, 694–696 (2013) Centers for Disease Control and Prevention (CDC) Multidrug-resistant Bacteroides fragilis-Seattle, Washington, 2013. MMWR Morb. Mortal. Wkly. Rep. 62 694 696 2013 Search in Google Scholar

Cobo F., Aliaga L., Expósito-Ruiz M., Navarro-Marí J.M.: Anaerobic bacteraemia: A score predicting mortality. Anaerobe, 64, doi: 10.1016/j.anaerobe.2020.102219 (2020) CoboF. AliagaL. Expósito-RuizM. Navarro-MaríJ.M. Anaerobic bacteraemia: A score predicting mortality Anaerobe 64 10.1016/j.anaerobe.2020.102219 2020 32531433 Open DOISearch in Google Scholar

Diniz C.G.: Differential gene expression in a Bacteroides fragilis metronidazole-resistant mutant. J. Antimicrob. Chemother. 54, 100–108 (2004) DinizC.G. Differential gene expression in a Bacteroides fragilis metronidazole-resistant mutant J. Antimicrob. Chemother. 54 100 108 2004 10.1093/jac/dkh25615150173 Search in Google Scholar

Dumont Y., Bonzon L., Michon A.L., Carriere C., Didelot M.N., Laurens C., Renard B., Veloo A.C.M., Godreuil S., Jean-Pierre H.: Epidemiology and microbiological features of anaerobic bacteraemia in two French University hospitals. Anaerobe, 64, doi: 10.1016/j.anaerobe.2020.102207 (2020) DumontY. BonzonL. MichonA.L. CarriereC. DidelotM.N. LaurensC. RenardB. VelooA.C.M. GodreuilS. Jean-PierreH. Epidemiology and microbiological features of anaerobic bacteraemia in two French University hospitals Anaerobe 64 10.1016/j.anaerobe.2020.102207 2020 32360436 Open DOISearch in Google Scholar

European Committee on Antimicrobial Susceptibility Testing: Clinical breakpoints – breakpoints and guidance v 12.0 January 1, 2022, https://www.eucast.org (01.02.2022) European Committee on Antimicrobial Susceptibility Testing Clinical breakpoints – breakpoints and guidance v 12.0 January 1, 2022 https://www.eucast.org (01.02.2022) Search in Google Scholar

Fenner L., Widmer A.F., Straub C., Frei R.: Is the incidence of anaerobic bacteraemia decreasing? Analysis of 114,000 blood cultures over a ten-year period. J. Clin. Microbiol. 46, 2432–2434 (2008) FennerL. WidmerA.F. StraubC. FreiR. Is the incidence of anaerobic bacteraemia decreasing? Analysis of 114,000 blood cultures over a ten-year period J. Clin. Microbiol. 46 2432 2434 2008 10.1128/JCM.00013-08244694218463219 Search in Google Scholar

Finegold S.M., George W.L., Mulligan M.E.: Anaerobic infections part II. Dis. Mon. 31, 1–97 (1985) FinegoldS.M. GeorgeW.L. MulliganM.E. Anaerobic infections part II Dis. Mon. 31 1 97 1985 10.1016/0011-5029(85)90027-6 Search in Google Scholar

Gajdács M., Urbán E.: Relevance of anaerobic bacteremia in adult patients: A never-ending story? Eur. J. Microbiol. Immunol. 5, 64–75 (2020) GajdácsM. UrbánE. Relevance of anaerobic bacteremia in adult patients: A never-ending story? Eur. J. Microbiol. Immunol. 5 64 75 2020 10.1556/1886.2020.00009739137932590337 Search in Google Scholar

Gao Q., Wu S., Xu T., Zhao X., Huang H., Hu F.: Emergence of carbapenem resistance in Bacteroides fragilis in China. Int. J. Antimicrob. Agents. 53, 859–863, (2019) GaoQ. WuS. XuT. ZhaoX. HuangH. HuF. Emergence of carbapenem resistance in Bacteroides fragilis in China Int. J. Antimicrob. Agents. 53 859 863 2019 10.1016/j.ijantimicag.2019.02.01730831235 Search in Google Scholar

Genzel G.H., Stubbings W., Stîngu C.S., Labischinski H., Schaumann R.: Activity of the investigational fluoroquinolone finafloxacin and seven other antimicrobial agents against 114 obligately anaerobic bacteria. Int. J. Antimicrob. Agents. 44, 420–423 (2014) GenzelG.H. StubbingsW. StînguC.S. LabischinskiH. SchaumannR. Activity of the investigational fluoroquinolone finafloxacin and seven other antimicrobial agents against 114 obligately anaerobic bacteria Int. J. Antimicrob. Agents. 44 420 423 2014 10.1016/j.ijantimicag.2014.07.00625264128 Search in Google Scholar

Grohs P., Mainardi J.L., Podglajen I., Hanras X., Eckert C., Buu-Hoi A., Varon E., Gutmann L.: Relevance of Routine Use of the Anaerobic Blood Culture Bottle. J. Clin. Microbiol. 45, 2711–2715 (2007) GrohsP. MainardiJ.L. PodglajenI. HanrasX. EckertC. Buu-HoiA. VaronE. GutmannL. Relevance of Routine Use of the Anaerobic Blood Culture Bottle J. Clin. Microbiol. 45 2711 2715 2007 10.1128/JCM.00059-07195126317581942 Search in Google Scholar

Hartmeyer G.N., Sóki J., Nagy E., Justesen U.S.: Multidrug-resistant Bacteroides fragilis group on the rise in Europe? J. Med. Microbiol. 61, 1784–1788 (2012) HartmeyerG.N. SókiJ. NagyE. JustesenU.S. Multidrug-resistant Bacteroides fragilis group on the rise in Europe? J. Med. Microbiol. 61 1784 1788 2012 10.1099/jmm.0.049825-022956754 Search in Google Scholar

Ho P.L., Yau C.Y., Ho L.Y., Lai E.L., Liu M.C., Tse C.W., Chow K.H.: Antimicrobial susceptibility of Bacteroides fragilis group organisms in Hong Kong by the tentative EUCAST disc diffusion method. Anaerobe, 47, 51–56 (2017) HoP.L. YauC.Y. HoL.Y. LaiE.L. LiuM.C. TseC.W. ChowK.H. Antimicrobial susceptibility of Bacteroides fragilis group organisms in Hong Kong by the tentative EUCAST disc diffusion method Anaerobe 47 51 56 2017 10.1016/j.anaerobe.2017.04.00528414107 Search in Google Scholar

Kaeuffer C., Ruge T., Diancourt L., Romain B., Ruch Y., Jaulhac B., Boyer P.H. First Case of Bacteraemia Due to Carbapenem-Resistant Bacteroides faecis. Antibiotics (Basel). 19, doi: 10.3390/antibiotics10030319 (2021) KaeufferC. RugeT. DiancourtL. RomainB. RuchY. JaulhacB. BoyerP.H. First Case of Bacteraemia Due to Carbapenem-Resistant Bacteroides faecis Antibiotics (Basel) 19 10.3390/antibiotics10030319 2021 800348133808699 Open DOISearch in Google Scholar

Karlowsky J.A., Walkty A.J., Adam H.J., Baxter M.R., Hoban D.J., Zhanel G.G.: Prevalence of Antimicrobial Resistance among Clinical Isolates of Bacteroides fragilis Group in Canada in 2010–2011: CANWARD Surveillance Study. Antimicrob. Agents Chemother. 56, 1247–1252 (2012) KarlowskyJ.A. WalktyA.J. AdamH.J. BaxterM.R. HobanD.J. ZhanelG.G. Prevalence of Antimicrobial Resistance among Clinical Isolates of Bacteroides fragilis Group in Canada in 2010–2011: CANWARD Surveillance Study Antimicrob. Agents Chemother. 56 1247 1252 2012 10.1128/AAC.05823-11329493922203594 Search in Google Scholar

Katsandri A., Papaparaskevas J., Pantazatou A., Petrikkos G.L., Thomopoulos G., Houhoula D.P., Avlamis A.: Two Cases of Infections Due to Multidrug-Resistant Bacteroides fragilis Group Strains. J. Clin. Microbiol. 44, 3465–3467 (2006) KatsandriA. PapaparaskevasJ. PantazatouA. PetrikkosG.L. ThomopoulosG. HouhoulaD.P. AvlamisA. Two Cases of Infections Due to Multidrug-Resistant Bacteroides fragilis Group Strains J. Clin. Microbiol. 44 3465 3467 2006 10.1128/JCM.00316-06159466616954304 Search in Google Scholar

De Keukeleire S., Wybo I., Naessens A., Echahidi F., Van der Beken M., Vandoorslaer K., Vermeulen S., Piérard D.: Anaerobic bacteraemia: A 10-year retrospective epidemiological survey. Anaerobe, 39, 54–59 (2016) De KeukeleireS. WyboI. NaessensA. EchahidiF. Van der BekenM. VandoorslaerK. VermeulenS. PiérardD. Anaerobic bacteraemia: A 10-year retrospective epidemiological survey Anaerobe 39 54 59 2016 10.1016/j.anaerobe.2016.02.00926923749 Search in Google Scholar

Kierzkowska M., Majewska A., Dobrzaniecka K., Sawicka-Grzelak A., Mlynarczyk A., Chmura A., Durlik M., Deborska-Materkowska D., Paczek L., Mlynarczyk G.: Blood Infections in Patients Treated at Transplantation Wards of a Clinical Hospital in Warsaw. Transplant. Proc. 46, 2589–2591 (2014) KierzkowskaM. MajewskaA. DobrzanieckaK. Sawicka-GrzelakA. MlynarczykA. ChmuraA. DurlikM. Deborska-MaterkowskaD. PaczekL. MlynarczykG. Blood Infections in Patients Treated at Transplantation Wards of a Clinical Hospital in Warsaw Transplant. Proc. 46 2589 2591 2014 10.1016/j.transproceed.2014.08.02425380873 Search in Google Scholar

Kierzkowska M., Majewska A., Mlynarczyk G. Trends and Impact in Antimicrobial Resistance Among Bacteroides and Parabacteroides Species in 2007–2012 Compared to 2013–2017. Microb. Drug Resist. 26, 1452–1457 (2020) KierzkowskaM. MajewskaA. MlynarczykG. Trends and Impact in Antimicrobial Resistance Among Bacteroides and Parabacteroides Species in 2007–2012 Compared to 2013–2017 Microb. Drug Resist. 26 1452 1457 2020 10.1089/mdr.2019.046232407191 Search in Google Scholar

Kierzkowska M., Majewska A., Sawicka-Grzelak A., Młynarczyk G.: Pałeczki gram-ujemne beztlenowo rosnące – diagnostyka i znaczenie kliniczne. Post. Mikrobiol. 55, 91–98 (2016) KierzkowskaM. MajewskaA. Sawicka-GrzelakA. MłynarczykG. Pałeczki gram-ujemne beztlenowo rosnące – diagnostyka i znaczenie kliniczne Post. Mikrobiol. 55 91 98 2016 Search in Google Scholar

Kim J., Lee Y., Park Y., Kim M., Choi J.Y., Yong D., Jeong S.H., Lee K.: Anaerobic Bacteraemia: Impact of Inappropriate Therapy on Mortality. Infect. Chemother. 48, 91–98 (2016) KimJ. LeeY. ParkY. KimM. ChoiJ.Y. YongD. JeongS.H. LeeK. Anaerobic Bacteraemia: Impact of Inappropriate Therapy on Mortality Infect. Chemother. 48 91 98 2016 10.3947/ic.2016.48.2.91494573227433379 Search in Google Scholar

Lassmamn B., Gustafson D.R., Wood C.M., Rosenblatt J.E.: Reemergence of anaerobic bacteraemia. Clin. Infect. Dis. 44, 895–900 (2007) LassmamnB. GustafsonD.R. WoodC.M. RosenblattJ.E. Reemergence of anaerobic bacteraemia Clin. Infect. Dis. 44 895 900 2007 10.1086/51219717342637 Search in Google Scholar

Lee Y., Park Y.J., Kim M.N., Uh Y., Kim M.S., Lee K.: Multicenter study of antimicrobial susceptibility of anaerobic bacteria in Korea in 2012. Ann. Lab. Med. 35, 479–786 (2015) LeeY. ParkY.J. KimM.N. UhY. KimM.S. LeeK. Multicenter study of antimicrobial susceptibility of anaerobic bacteria in Korea in 2012 Ann. Lab. Med. 35 479 786 2015 10.3343/alm.2015.35.5.479451049926206683 Search in Google Scholar

Löfmark S., Edlund C., Nord Carl E.: Metronidazole Is Still the Drug of Choice for Treatment of Anaerobic Infections. Clin. Infect. Dis. 50, (2010) LöfmarkS. EdlundC. Nord CarlE. Metronidazole Is Still the Drug of Choice for Treatment of Anaerobic Infections Clin. Infect. Dis. 50 2010 10.1086/64793920067388 Search in Google Scholar

Mukhopadhyay S., Puopolo K.M.: Relevance of Neonatal Anaerobic Blood Cultures: New Information for an Old Question. J. Pediatric Infect. Dis. Soc. 17, 126–127 (2018) MukhopadhyayS. PuopoloK.M. Relevance of Neonatal Anaerobic Blood Cultures: New Information for an Old Question J. Pediatric Infect. Dis. Soc. 17 126 127 2018 10.1093/jpids/pix09529165632 Search in Google Scholar

Nagy E.: Anaerobic infections: update on treatment considerations. Drugs, 70, 841–858 (2010) NagyE. Anaerobic infections: update on treatment considerations Drugs 70 841 858 2010 10.2165/11534490-000000000-0000020426496 Search in Google Scholar

Nagy E., Urbán E.: Antimicrobial susceptibility of Bacteroides fragilis group isolates in Europe: 20 years of experience. Clin. Microbiol. Infect. 17, 371–379 (2011) NagyE. UrbánE. Antimicrobial susceptibility of Bacteroides fragilis group isolates in Europe: 20 years of experience Clin. Microbiol. Infect. 17 371 379 2011 10.1111/j.1469-0691.2010.03256.x20456453 Search in Google Scholar

Nagy E., Boyanova L., Justesen U.S.: ESCMID Study Group of Anaerobic Infections. How to isolate, identify and determine antimicrobial susceptibility of anaerobic bacteria in routine laboratories. Clin. Microbiol. Infect. 24, 1139–1148 (2018) NagyE. BoyanovaL. JustesenU.S. ESCMID Study Group of Anaerobic Infections. How to isolate, identify and determine antimicrobial susceptibility of anaerobic bacteria in routine laboratories Clin. Microbiol. Infect. 24 1139 1148 2018 10.1016/j.cmi.2018.02.008 Search in Google Scholar

Ngo J.T., Parkins M.D., Gregson D.B., Pitout J.D.D., Ross T., Church D.L., Laupland K.B.: Population-based assessment of the incidence, risk factors, and outcomes of anaerobic bloodstream infections. Infection, 41, 41–48 (2013) NgoJ.T. ParkinsM.D. GregsonD.B. PitoutJ.D.D. RossT. ChurchD.L. LauplandK.B. Population-based assessment of the incidence, risk factors, and outcomes of anaerobic bloodstream infections Infection 41 41 48 2013 10.1007/s15010-012-0389-4 Search in Google Scholar

Nguyen M.H., Yu V.L., Morris A.J., McDermott L., Wagener M.W., Harrell L., Snydman D.R.: Antimicrobial Resistance and Clinical Outcome of Bacteroides Bacteraemia: Findings of a Multicenter Prospective Observational Trial. Clin. Infect. Dis. 30, 870–876 (2000) NguyenM.H. YuV.L. MorrisA.J. McDermottL. WagenerM.W. HarrellL. SnydmanD.R. Antimicrobial Resistance and Clinical Outcome of Bacteroides Bacteraemia: Findings of a Multicenter Prospective Observational Trial Clin. Infect. Dis. 30 870 876 2000 10.1086/313805 Search in Google Scholar

Ogane K., Maeda T. et al: Antimicrobial susceptibility and prevalence of resistance genes in Bacteroides fragilis isolated from blood culture bottles in two tertiary care hospitals in Japan. Anaerobe, 64, doi: 10.1016/j.anaerobe.2020.102215 (2020) OganeK. MaedaT. Antimicrobial susceptibility and prevalence of resistance genes in Bacteroides fragilis isolated from blood culture bottles in two tertiary care hospitals in Japan Anaerobe 64 10.1016/j.anaerobe.2020.102215 2020 Open DOISearch in Google Scholar

Patrick S., Duerden B.I.: Non-Sporing Gram-Negative Anaerobes (in) Principles and Practice of Clinical Bacteriology, Second Edition, Eds. Stephen H. Gillespie S.H., Hawkey P.M., John Wiley & Sons, 2006, 541–556 PatrickS. DuerdenB.I. Non-Sporing Gram-Negative Anaerobes (in) Principles and Practice of Clinical Bacteriology Second Edition Eds. StephenH. GillespieS.H. HawkeyP.M. John Wiley & Sons 2006 541 556 10.1002/9780470017968.ch45 Search in Google Scholar

Philippon A., Slama P., Dény P., Labia R.: A Structure-Based Classification of Class A β-Lactamases, a Broadly Diverse Family of Enzymes. Clin. Microbiol. Rev. 29, 29–59 (2016) PhilipponA. SlamaP. DényP. LabiaR. A Structure-Based Classification of Class A β-Lactamases, a Broadly Diverse Family of Enzymes Clin. Microbiol. Rev. 29 29 59 2016 10.1128/CMR.00019-15 Search in Google Scholar

Robert R., Deraignac A., Le Moal G., Ragot S., Grollier G. Prognostic factors and impact of antibiotherapy in 117 cases of anaerobic bacteraemia. Eur. J. Clin. Microbiol. Infect. Dis. 27, 671–678 (2008) RobertR. DeraignacA. Le MoalG. RagotS. GrollierG. Prognostic factors and impact of antibiotherapy in 117 cases of anaerobic bacteraemia Eur. J. Clin. Microbiol. Infect. Dis. 27 671 678 2008 10.1007/s10096-008-0487-5 Search in Google Scholar

Rodloff A.C., Dowzicky M.J.: In vitro activity of tigecycline and comparators against a European collection of anaerobes collected as part of the Tigecycline Evaluation and Surveillance Trial (T.E.S.T.) 2010–2016. Anaerobe, 51, 78–88 (2018) RodloffA.C. DowzickyM.J. In vitro activity of tigecycline and comparators against a European collection of anaerobes collected as part of the Tigecycline Evaluation and Surveillance Trial (T.E.S.T.) 2010–2016 Anaerobe 51 78 88 2018 10.1016/j.anaerobe.2018.04.009 Search in Google Scholar

Rodrigues C., Siciliano R.F., Zeigler R., Strabelli T.M.: Bacteroides fragilis endocarditis: A case report and review of literature. Braz. J. Infect. Dis. 16, 100–104 (2012) RodriguesC. SicilianoR.F. ZeiglerR. StrabelliT.M. Bacteroides fragilis endocarditis: A case report and review of literature Braz. J. Infect. Dis. 16 100 104 2012 10.1016/S1413-8670(12)70285-4 Search in Google Scholar

Roh K.H., Kim S., Kim C.K., Yum J.H., Kim M.S., Yong D., Jeong S.H., Lee K., Kim J.M., Chong Y.: New cfiA variant and novel insertion sequence elements in carbapenem-resistant Bacteroides fragilis isolates from Korea. Diagn. Microbiol. Infect. Dis. 66, 343–348 (2010) RohK.H. KimS. KimC.K. YumJ.H. KimM.S. YongD. JeongS.H. LeeK. KimJ.M. ChongY. New cfiA variant and novel insertion sequence elements in carbapenem-resistant Bacteroides fragilis isolates from Korea Diagn. Microbiol. Infect. Dis. 66 343 348 2010 10.1016/j.diagmicrobio.2009.11.00320226324 Search in Google Scholar

Rong S.M.M., Rodloff A.C., Stingu C.S.: Diversity of antimicrobial resistance genes in Bacteroides and Parabacteroides strains isolated in Germany. J. Glob. Antimicrob. Resist. 24, 328–334 (2021) RongS.M.M. RodloffA.C. StinguC.S. Diversity of antimicrobial resistance genes in Bacteroides and Parabacteroides strains isolated in Germany J. Glob. Antimicrob. Resist. 24 328 334 2021 10.1016/j.jgar.2021.01.00733508481 Search in Google Scholar

Sanford Guide: Antibacterial agents: Spectra of Activity, https://webedition.sanfordguide.com/en (01.02.2022) Sanford Guide Antibacterial agents: Spectra of Activity https://webedition.sanfordguide.com/en (01.02.2022) Search in Google Scholar

Schuetz A.N.: Antimicrobial Resistance and Susceptibility Testing of Anaerobic Bacteria. Clin. Infect. Dis. 59, 698–705 (2014) SchuetzA.N. Antimicrobial Resistance and Susceptibility Testing of Anaerobic Bacteria Clin. Infect. Dis. 59 698 705 2014 10.1007/978-3-319-78538-7_6 Search in Google Scholar

Shafquat Y., Jabeen K., Farooqi J., Mehmood K., Irfan S., Hasan R., Zafar A.: Antimicrobial susceptibility against metronidazole and carbapenem in clinical anaerobic isolates from Pakistan. Antimicrob. Resist. Infect. Control. 14, doi: 10.1186/s13756-019-0549-8 (2019) ShafquatY. JabeenK. FarooqiJ. MehmoodK. IrfanS. HasanR. ZafarA. Antimicrobial susceptibility against metronidazole and carbapenem in clinical anaerobic isolates from Pakistan Antimicrob. Resist. Infect. Control. 14 10.1186/s13756-019-0549-8 2019 656747931210928 Open DOISearch in Google Scholar

Sherwood J.E., Fraser S., Citron D.M., Wexler H., Blakely G., Jobling K., Patrick S.: Multi-drug resistant Bacteroides fragilis recovered from blood and severe leg wounds caused by an improvised explosive device (IED) in Afghanistan. Anaerobe, 17, 152–155 (2011) SherwoodJ.E. FraserS. CitronD.M. WexlerH. BlakelyG. JoblingK. PatrickS. Multi-drug resistant Bacteroides fragilis recovered from blood and severe leg wounds caused by an improvised explosive device (IED) in Afghanistan Anaerobe 17 152 155 2011 10.1016/j.anaerobe.2011.02.00721376821 Search in Google Scholar

Shimura S., Wada Y. et al: Antimicrobial susceptibility surveillance of obligate anaerobic bacteria in the Kinki area. J. Infect. Chemother. 25, 837–844 (2019) ShimuraS. WadaY. Antimicrobial susceptibility surveillance of obligate anaerobic bacteria in the Kinki area J. Infect. Chemother. 25 837 844 2019 10.1016/j.jiac.2019.07.01831427200 Search in Google Scholar

Snydman D.R., Jacobus N.V., McDermott L.A., Goldstein E.J.C., Harrell L., Jenkins S.G., Newton D., Patel R., Hecht D.W.: Trends in antimicrobial resistance among Bacteroides species and Parabacteroides species in the United States from 2010–2012 with comparison to 2008–2009. Anaerobe, 43, 21–26 (2017) SnydmanD.R. JacobusN.V. McDermottL.A. GoldsteinE.J.C. HarrellL. JenkinsS.G. NewtonD. PatelR. HechtD.W. Trends in antimicrobial resistance among Bacteroides species and Parabacteroides species in the United States from 2010–2012 with comparison to 2008–2009 Anaerobe 43 21 26 2017 10.1016/j.anaerobe.2016.11.00327867083 Search in Google Scholar

Sóki J.: Extended role for insertion sequence elements in the antibiotic resistance of Bacteroides. World J. Clin. Infect. Dis. 3, 1–12 (2013) SókiJ. Extended role for insertion sequence elements in the antibiotic resistance of Bacteroides World J. Clin. Infect. Dis. 3 1 12 2013 10.5495/wjcid.v3.i1 Search in Google Scholar

Sóki J., Gonzalez S.M., Urban E., Nagy E., Ayala J.A.: Molecular analysis of the effector mechanisms of cefoxitin resistance among Bacteroides strains. J. Antimicrob. Chemother. 66, 2492–500 (2011) SókiJ. GonzalezS.M. UrbanE. NagyE. AyalaJ.A. Molecular analysis of the effector mechanisms of cefoxitin resistance among Bacteroides strains J. Antimicrob. Chemother. 66 2492 500 2011 10.1093/jac/dkr33921873290 Search in Google Scholar

Song Y.L., Liu C.X., McTeague M., Finegold S.M.: “Bacteroides nordii” sp. nov. and “Bacteroides salyersae” sp. nov. Isolated from Clinical Specimens of Human Intestinal Origin. J. Clin. Microbiol. 42, 5565–5570 (2004) SongY.L. LiuC.X. McTeagueM. FinegoldS.M. Bacteroides nordii” sp. nov. and “Bacteroides salyersae” sp. nov. Isolated from Clinical Specimens of Human Intestinal Origin J. Clin. Microbiol. 42 5565 5570 2004 10.1128/JCM.42.12.5565-5570.200453527415583282 Search in Google Scholar

Snydman D.R., Gorbach S.L. et al: Lessons learned from the anaerobe survey: historical perspective and review of the most recent data (2005–2007). Clin. Infect. Dis. 50, 26–33 (2010) SnydmanD.R. GorbachS.L. Lessons learned from the anaerobe survey: historical perspective and review of the most recent data (2005–2007) Clin. Infect. Dis. 50 26 33 2010 10.1086/64794020067390 Search in Google Scholar

Snydman D.R., Hecht D.W. et al: Update on resistance of Bacteroides fragilis group and related species with special attention to carbapenems 2006–2009. Anaerobe, 17, 147–151 (2011) SnydmanD.R. HechtD.W. Update on resistance of Bacteroides fragilis group and related species with special attention to carbapenems 2006–2009 Anaerobe 17 147 151 2011 10.1016/j.anaerobe.2011.05.014 Search in Google Scholar

Tan T.Y., Ng L.S.Y., Kwang L.L., Rao S., Eng L.C.: Clinical characteristics and antimicrobial susceptibilities of anaerobic bacteraemia in an acute care hospital. Anaerobe, 43, 69–74 (2017) TanT.Y. NgL.S.Y. KwangL.L. RaoS. EngL.C. Clinical characteristics and antimicrobial susceptibilities of anaerobic bacteraemia in an acute care hospital Anaerobe 43 69 74 2017 10.1016/j.anaerobe.2016.11.009 Search in Google Scholar

Toprak N.U., Uzunkaya O.D., Sóki J., Soyletir G.: Susceptibility profiles and resistance genes for carbapenems (cfiA) and metronidazole (nim) among Bacteroides species in a Turkish University Hospital. Anaerobe, 18, 169–171 (2012) ToprakN.U. UzunkayaO.D. SókiJ. SoyletirG. Susceptibility profiles and resistance genes for carbapenems (cfiA) and metronidazole (nim) among Bacteroides species in a Turkish University Hospital Anaerobe 18 169 171 2012 10.1016/j.anaerobe.2011.10.004 Search in Google Scholar

Turner P., Edwards R., Weston V., Ispahani P., Greenwood D., Gazis A.: Simultaneous resistance to metronidazole, co-amoxiclav, and imipenem in clinical isolate of Bacteroides fragilis. The Lancet, 345, 1275–1277 (1995) TurnerP. EdwardsR. WestonV. IspahaniP. GreenwoodD. GazisA. Simultaneous resistance to metronidazole, co-amoxiclav, and imipenem in clinical isolate of Bacteroides fragilis The Lancet 345 1275 1277 1995 10.1016/S0140-6736(95)90927-3 Search in Google Scholar

Umemura T., Hamada Y., Yamagishi Y., Suematsu H., Mikamo H.: Clinical characteristics associated with mortality of patients with anaerobic bacteraemia. Anaerobe, 39, 45–50 (2016) UmemuraT. HamadaY. YamagishiY. SuematsuH. MikamoH. Clinical characteristics associated with mortality of patients with anaerobic bacteraemia Anaerobe 39 45 50 2016 10.1016/j.anaerobe.2016.02.00726903282 Search in Google Scholar

Urbán E.: Five-year retrospective epidemiological survey of anaerobic bacteraemia in a University Hospital and Review of the Literature. Eur. J. Microbiol. Immunol. (Bp). 2, 140–147 (2012) UrbánE. Five-year retrospective epidemiological survey of anaerobic bacteraemia in a University Hospital and Review of the Literature Eur. J. Microbiol. Immunol. (Bp). 2 140 147 2012 10.1556/EuJMI.2.2012.2.7395696324672683 Search in Google Scholar

Vena A., Muñoz P., Alcalá L., Fernandez-Cruz A., Sanchez C., Valerio M., Bouza E.: Are incidence and epidemiology of anaerobic bacteraemia really changing? Eur. J. Clin. Microbiol. Infect. Dis. 34, 1621–1629 (2015) VenaA. MuñozP. AlcaláL. Fernandez-CruzA. SanchezC. ValerioM. BouzaE. Are incidence and epidemiology of anaerobic bacteraemia really changing? Eur. J. Clin. Microbiol. Infect. Dis. 34 1621 1629 2015 10.1007/s10096-015-2397-726017663 Search in Google Scholar

Wang F.D., Liao C.H., Lin Y.T., Sheng W.H., Hsueh P.R.: Trends in the susceptibility of commonly encountered clinically significant anaerobes and susceptibilities of blood isolates of anaerobes to 16 antimicrobial agents, including fidaxomicin and rifaximin, 2008–2012, northern Taiwan. Eur. J. Clin. Microbiol. Infect. Dis. 33, 2041–2052 (2014) WangF.D. LiaoC.H. LinY.T. ShengW.H. HsuehP.R. Trends in the susceptibility of commonly encountered clinically significant anaerobes and susceptibilities of blood isolates of anaerobes to 16 antimicrobial agents, including fidaxomicin and rifaximin, 2008–2012, northern Taiwan Eur. J. Clin. Microbiol. Infect. Dis. 33 2041 2052 2014 10.1007/s10096-014-2175-y24930042 Search in Google Scholar

Wareham D.W., Wilks M., Ahmed D., Brazier J.S., Millar M.: Anaerobic Sepsis Due to Multidrug-Resistant Bacteroides fragilis: Microbiological Cure and Clinical Response with Linezolid Therapy. Clin. Infect. Dis. 40, 67–68 (2005) WarehamD.W. WilksM. AhmedD. BrazierJ.S. MillarM. Anaerobic Sepsis Due to Multidrug-Resistant Bacteroides fragilis: Microbiological Cure and Clinical Response with Linezolid Therapy Clin. Infect. Dis. 40 67 68 2005 10.1086/428623 Search in Google Scholar

Wexler H.M.: Bacteroides: the Good, the Bad, and the Nitty-Gritty. Clin. Microbiol. Rev. 20, 593–621 (2007) WexlerH.M. Bacteroides: the Good, the Bad, and the Nitty-Gritty Clin. Microbiol. Rev. 20 593 621 2007 10.1128/CMR.00008-07217604517934076 Search in Google Scholar

Wexler H.M.: The Genus Bacteroides (in) The Prokaryotes, eds. Rosenberg E., DeLong E.F., Lory S., Stackebrandt E., Thompson F., Springer, Berlin, 2014, 459–484 WexlerH.M. The Genus Bacteroides (in) The Prokaryotes eds. RosenbergE. DeLongE.F. LoryS. StackebrandtE. ThompsonF. Springer Berlin 2014 459 484 10.1007/978-3-642-38954-2_129 Search in Google Scholar

Yarbrough M.L., Wallace M.A., Burnham C.D.: Comparision of microorganism detection and time to positivity in pediatric and standard media from three major commercial continuously monitored blood culture systems. J. Clin. Microbiol. 59, e00429–21 (2021) YarbroughM.L. WallaceM.A. BurnhamC.D. Comparision of microorganism detection and time to positivity in pediatric and standard media from three major commercial continuously monitored blood culture systems J. Clin. Microbiol. 59 e00429 21 2021 10.1128/JCM.00429-21 Search in Google Scholar

Yoshino Y., Kitazawa T., Ikeda M., Tatsuno K., Yanagimoto S., Okugawa S., Ota Y., Yotsuyanagi H.: Clinical features of Bacteroides bacteraemia and their association with colorectal carcinoma. Infection, 40, 63–67 (2012) YoshinoY. KitazawaT. IkedaM. TatsunoK. YanagimotoS. OkugawaS. OtaY. YotsuyanagiH. Clinical features of Bacteroides bacteraemia and their association with colorectal carcinoma Infection 40 63 67 2012 10.1007/s15010-011-0159-821773761 Search in Google Scholar

Zafar H., Saier M.H. Jr. Gut Bacteroides species in health and disease. Gut Microbes, 13, 1–20 (2021) ZafarH. SaierM.H.Jr. Gut Bacteroides species in health and disease Gut Microbes 13 1 20 2021 10.1080/19490976.2020.1848158787203033535896 Search in Google Scholar

Zahar J.R., Farhat H., Chachaty E., Meshaka P., Antoun S., Nitenberg G. Incidence and clinical significance of anaerobic bacteraemia in cancer patients: a 6-year retrospective study. Clin. Microbiol. Infect. 11, 724–729 (2005) ZaharJ.R. FarhatH. ChachatyE. MeshakaP. AntounS. NitenbergG. Incidence and clinical significance of anaerobic bacteraemia in cancer patients: a 6-year retrospective study Clin. Microbiol. Infect. 11 724 729 2005 10.1111/j.1469-0691.2005.01214.x16104987 Search in Google Scholar

Recommended articles from Trend MD