Skip to main content

Two cases of bloodstream infections associated with opportunistic bacterial species (Enterococcus hirae and Enterobacter xiangfangensis) in companion animals



Bloodstream infections are a matter of concern in small animal veterinary practice. Few reports are avaiable, especially regarding the role of opportunistic bacteria in becoming infectious. This report aims to add to the current veterinary literature on two opportunistic bacterial species (Enterococcus hirae and Enterobacter xiangfangensis) associated with bloodstream infections in small animals admitted to the Bologna University Veterinary Hospital.

Case presentation

In the first case, a 15-year-old, immunocompromised, cardiopathic dog was admitted to the hospital for anorexia and diarrhea. The patient had a history of previous surgery and hospitalization. After three days, hyperthermia, leukopenia and hyperlactatemia were recorded, and blood culture revealed positivity for Enterococcus hirae, identified using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). The patient’s general conditions progressively worsened, and the patient was euthanized. In the second case, a 2-year-old cat with chronic ocular herpesvirus infection and hypertrophic cardiomyopathy was admitted to the hospital for anorexia and hyperthermia. The cat was hospitalized one week before and received antimicrobial treatment for urinary tract infection by Staphylococcus felis. Hypokalemia and lymphopenia were also diagnosed. The patient progressively improved and was discharged after three days. On the same day, blood culture taken at admission revealed positivity for Enterobacter xiangfangensis, identified using MALDI-TOF MS. After five days, the patient returned with neurological symptoms, hypothermia and bradycardia, and was euthanized.


In small animal veterinary practice, the impact of opportunistic bacterial agents (such as E.hirae and E.xiangfangensis) on bloodstream infections remains unclear. As in human medicine, they can be contracted in every healthcare setting and considered hospital-acquired infections. In this report, we highlighted the threat they pose especially in patients with multiple risk factors. Rapid and accurate diagnostic tools (such as MALDI-TOF MS) could be particularly important for reducing the severity of the infections.


Bloodstream bacterial infections are a common finding in both human and veterinary medicine and are considered an important cause of morbidity and mortality [1, 2]. Bloodstream infections not secondary to an infection at another body site are suggestive of a hospital-acquired infection (HAI), normally associated with the presence of intravascular devices such as central venous catheters [3]. Catheter-related bloodstream infections (CRBIs) are a frequent complication in immune-compromised and hospitalized patients with a high mortality rate. Microorganisms responsible for CRBI, other than well-known species such as Escherichia coli, Klebsiella pneumoniae or Staphylococcus spp., might include uncommon bacterial species, mostly commensal or opportunistic [4]. In small animal veterinary medicine, few epidemiological data are available concerning the role of environmental or commensal bacteria in the development of bloodstream infections in hospitalized patients. The aim of this report is to describe two clinical cases of bloodstream infections associated with opportunistic bacterial species in small animals hospitalized at the Bologna University Veterinary Hospital (UVH) of the Department of Veterinary Medical Sciences.

Cases description

First case. A mixed breed of 15 years old female spayed dog weighing 16 kg was presented at the emergency service of the Bologna UVH for acute onset anorexia and diarrhea. On physical examination the dog was depressed with nausea, mild dehydration and a normal rectal temperature (38.5 °C). Blood profile showed lymphopenia (580 cells/mm3), mild hyperbilirubinemia (0.47 mg/dL), and a serum C-reactive protein (CRP) concentration within normal limits (0.9 mg/dL). Ultrasound examination was suggestive of an acute gastroenteritis with delayed gastric emptying. The dog had a past diagnosis of a subcutaneous mast cell tumor to the cranial tibial plate with involvement of the regional lymph nodes, which was surgically removed two months before, and was put on treatment with 2,5 mg/m2 vinblastine every three weeks (Velbe, EG Stada) and 1 mg/kg q 24 h prednisolone (Prednicortone, Dechra). Furthermore, the patient was affected by a myxomatous degeneration of both mitral and tricuspid valves and was on cardiologic therapy with 0.25–0.5 mg/kg q 24 h benazepril (Fortekor, Elanco), 0.25–0.5 mg/kg q 12 h pimobendan (Vetmedin, Boehringer Ingelheim) and 2 mg/kg q 12 h furosemide (Diuren, Teknofarma). Gastrointestinal (GI) toxicity by vinblastine was suspected based on history and clinical presentation and the dog was hospitalized in the general ward for monitoring and supportive treatment. On the third day of hospitalization, the dog developed a severe febrile neutropenia (rectal body temperature: 40,3 °C; white blood cell (WBC) count: 750 cells/mm3; neutrophil count: 230 cells/mm3) associated with ongoing GI signs. Blood chemistry revealed a significant increase in serum CRP (25.72 mg/dL) and onset of azotemia (creatinine: 1.77 mg/dL), indicative of acute kidney injury. Blood culture was then performed by inoculating 10 ml of blood into a commercially available blood culture bottle (Signal Blood Culture System; Oxoid, Milan, Italy) incubated at 37 ± 1 °C. The patient was then transferred to the Intensive Care Unit and empirical broad-spectrum antimicrobial treatment with piperacillin-tazobactam (50 mg/kg, IV q 6 h) was started. At 24 h, the blood culture was positive for the presence of microorganisms in the bloodstream. After subculturing at 37 ± 1 °C for 24 h in media plates for aerobic and anaerobic bacteria, Enterococcus hirae was identified. Bacterial identification was performed using the matrix-assisted laser desorption-ionization time-of-flight mass spectrometry method (MALDI-TOF MS;Biotyper, Bruker Daltonics, Billerica, MA), following manifacturer’s instructions (Bruker Daltonik, Bremen, Germany), with a final ID score of 2.35 (high-confidence identification) using the BRUKER BIOTYPER version 3.0 software. General clinical condition progressively worsened with persistent hyperthermia (40 °C) and onset of septic shock requiring hemodynamic support with vasopressors. In the following hours, multiorgan failure developed, and owners elected to euthanized their dog. Antimicrobial susceptibility testing of the isolated strain was performed using the Kirby–Bauer disk diffusion method, according to Clinical and Laboratory Standards Institute guidelines [5] and revealed resistance against clindamycin and rifampicin over a total of 17 antimicrobials tested.

Second case. A domestic, short-hair of 2 years old male castrated cat, weighing 5 kg, was referred to the Bologna VUH by the attending vet for the onset in the last week of lethargy, anorexia, vomiting and behavioral changes (hiding). The cat was initially treated and hospitalized in the referring practice, where a diagnosis of urinary tract infection by Staphylococcus felis was made and treatment with 2 mg/kg q 24 h marbofloxacin (Marbocyl, Vetoquinol) was instituted. Past history included chronic ocular herpesvirus infection treated with antiviral medication and a diagnosis of hypertrophic cardiomyopathy. At the hospital, the cat presented with dull mentation and hyperthermia (39.6 °C). blood culture was performed at admission by inoculating 5 ml of blood in the same commercially available bottle (Signal Blood Culture System; Oxoid, Milan, Italy) incubated at 37 ± 1° C. Blood examination results were unremarkable, except for an increased Serum Amyloid-A concentration (153 µg/mL) and positive test for Feline Leukemia Virus. During hospitalization, supportive treatment was instituted and intravenous marbofloxacin was continued. Clinical condition improved and the patient was discharged after three days. However, blood culture revealed positivity for Enterobacter xiangfangensis, identified after subculture at 37 ± 1° C for 24 h in media plates for aerobic and anaerobic bacteria, using MALDI-TOF MS with a final ID score of 2.41 (high-confidence identification). The isolated strain was subjected to antimicrobial susceptibility testing performed using the Kirby–Bauer disk diffusion method according to Clinical and Laboratory Standards Institute guidelines [5], and it showed resistance against all 14 tested antimicrobials, with the exception of amikacin and gentamycin. After 5 days, the patient was presented to the neurology service with severe neurological signs (stupor, pleurothotonus, head tilt, non-ambulatory tetraparesis, absent menace response, anisocoria), hypothermia (37.6 °C) and bradycardia (120 beats/min). A multifocal disease of inflammatory/infectious origin affecting the forebrain and brainstem was primarily suspected. A Magnetic Resonance Imaging was initially considered as a further diagnostic step, but due to the rapid deterioration of clinical signs, the cat was euthanized with the owner’s consent.

Discussion and conclusions

In this study, we describe two cases of bloodstream infections associated with opportunistic bacterial agents in immunocompromised companion animals. Studies suggest that enteric or environmental bacteria can access the bloodstream through contamination of intravascular devices such as jugular and intravenous catheters [6, 7]. Such contamination can be associated with poor skin preparation or contaminated personnel’s hands or materials used in skin preparation [8, 9]. The catheter site should always be considered a potential source of infection if hyperthermia is registered and may occur without any externally detectable alteration of the site, mostly because of the intraluminal colonization of bacteria [10, 11]. Indeed, a study from human medicine by Safdar and Maki suggests that local inflammation is a rare event, and site appearance may not be predictive for the presence of CRBI [12]. In the presented cases, no inflammation was observed at the insertion site of the catheter. Opportunistic bacteria causing bloodstream infections can also have a urinary source or arise from the gastroenteric tract in patients with intra-abdominal pathologies or neutropenia. None of the cases described in this study presented additional positive bacteriological cultures from other body districts, and no further investigation of the source of the infection was performed. A positive blood culture for a bacterial species that is part of the normal cutaneous flora should be not considered as significant pathogen in an asymptomatic patient because of the potential contamination from the skin during blood sampling, but on the other hand any bacterial species that have virulence factors can potentially cause bacteremia or sepsis, especially in immunosuppressed patients [13, 14]. Although routine culture of catheters is not recommended, the present study has the limitation that a deeper investigation of the source of the septic picture, such as a bacteriologic culture of the catheter tip or insertion site, was not conducted. Also, autopsies and histopathological examinations were not performed in both cases, so a definitive diagnosis was not possible. Nevertheless, the association of a positive blood culture with clinical symptoms such as hyperthermia, tachycardia or bradycardia in patients with multiple risk factors suggests that it should be considered a real ongoing infection rather than contamination. In addition, both cases can be considered potential HAIs, following the definition given by Haque et al. [3]. To our knowledge, this report is the first to describe E. hirae and E. xiangfangensis as bloodstream infection agents in dogs and cats, respectively. In the first case, bacteremia caused by Enterococcus hirae was described in a dog. E.hirae is a gram-positive bacterium, commonly considered part of the fecal microbiota in animals such as bovines [15], poultry [16], dogs and cats [17, 18]. According to published reports, in humans it is rarely associated with infections, but the few cases always reported severe illnesses, such as acute pyelonephritis [19], endocarditis [20] spontaneous bacterial peritonitis [21] and acute cholecystitis [19], always associated with bacteremia, and in some cases with septic shock [22]. Moreover, Bourafa et al. [23] reported a case report of a urinary tract infection in a man caused by E.hirae, suggesting its potential role as ascending bacteria. The potential zoonotic transmission of the agent from cats to humans has been suggested by Blaseg and Hoover [24], reporting a wound infection caused by E. hirae associated with cat litter. In livestock animals, outbreaks in broiler flocks have been associated with E. hirae, which was isolated from sucking rabbits with diarrhea [25]. In companion animals, it has been described by van Loon et al. [26] as a bloodstream infection agent in a cat with bacteremia and endocarditis, but also as a cause of cholangitis and pancreatitis [27] and as an opportunistic intestinal pathogen in kittens [28], although Ghosh et al. [29] demonstrated that it is more commonly isolated in healthy kittens rather than in sick ones.

In the presented case, given the bacteremia associated with E. hirae, it can be considered as an opportunistic infectious agent in a patient with multiple risk factors (age, immunodeficiency, previous hospitalization). In the second case, bacteremia in a cat was sustained by E. xiangfangensis, a gram-negative bacterial species part of the Enterobacter cloacae complex (ECC). These bacteria are saprophytic in the environment and are also part of the gut microbiota of humans and animals [30,31,32], but they are also often related with HAIs in humans [33]. It was firstly described in 2014 as a new taxonomic species [34] and is associated with the production of antimicrobial-resistance enzymes such as metallo-β-lactamase, methylases [35] and carbapenemases [36]. According to Wu et al. [37], E. xiangfangensis was the dominant Enterobacter species isolated from 48 bloodstream infections at Sichuan University Hospital, and was associated with higher death rate, longer hospitalizations, and higher resistance to different antimicrobial classes. Its potential relation with neonatal sepsis has also been suggested [38]. Its relatively recent classification has led to a lack of case descriptions in veterinary medicine. It has been isolated from the intestinal tract of healthy armored catfishes (Pterygoplichthys multiradiatus) [39], and spontaneously fermented dairy products [40]. In companion animals, Daniels et al. [41] described E. xianfangensis as urinary tract and wound infection agent in two dogs, in both cases carrying carbapenemase genes. In the present case, bacteremia associated with E. xiangfangensis appeared in a patient with risk factors like immunodeficiency and previous hospitalization. Bacterial identification was possible in both cases due to the MALDI-TOF MS technology, which is an extremely effective tool in terms of rapidity and accuracy in laboratory diagnostics. Indeed, this technology is faster and more accurate than conventional phenotypic identification methods [42], leading to a species-level identification within minutes starting from an isolated bacterial colony. Compared with genotypic diagnostic methods, such as PCR or 16 S rRNA sequencing, it is more rapid, giving the chance to reduce severe clinical outcomes, and requires less technical demands, normally available only in reference laboratories. In conclusion, this study highlights the role of E.hirae and E.xiangfangensis, two opportunistic bacterial species, as agents of bacteremia in companion animals. Bloodstream infections caused by these agents can often be contracted in any healthcare setting, especially in patients with risk factors, leading to sepsis and poor outcomes, such as in the described cases. Their impact as opportunistic agents and their infection rates in small animal veterinary medicine have probably been underestimated in the past years and should be further investigated. Considering the threat they pose, a rapid and accurate diagnostic method (such as MALDI-TOF MS) for their identification might be particularly important to reduce the possibility of poor prognosis.

Data Availability

Data sharing is not applicable to this article as no datasets were generated or analyzed during the current study.



matrix-assisted laser desorption/ionization time-of-flight mass spectrometry


Hospital-Acquired Infection


Catheter-Related Bloodstream Infection


University Veterinary Hospital


serum C-reactive protein




white blood cells


Enterobacter cloacae complex


  1. De Laforcade AM, Freeman LM, Shaw SP, Brooks MB, Rozanski EA, Rush JE. Hemostatic changes in dogs with naturally occurring sepsis. J Vet Intern Med. 2003;17:674–9.

    Article  PubMed  Google Scholar 

  2. Davies MG, Hagen PO. Systemic inflammatory response syndrome. Br J Surg. 1997;84:920–35.

    Article  CAS  PubMed  Google Scholar 

  3. Haque M, Sartelli M, McKimm J, Abu Bakar MB. Health care-associated infections: an overview. Infect drug Resist. 2018;11:2321–33.

    Article  PubMed  PubMed Central  Google Scholar 

  4. Mirijello A, Impagnatiello M, Zaccone V, Ventura G, Pompa L, Addolorato G, Landolfi R. Catheter-related bloodstream infections by opportunistic pathogens in immunocompromised hosts. Eur Rev Med Pharmacol Sci. 2015;19(13):2440–5.

    CAS  PubMed  Google Scholar 

  5. Wayne PA. Performance Standards for Antimicrobial Disk and Dilution Susceptibility Tests for Bacteria Isolated from Animals; Approved Standard.Clin Lab Stand Inst. 2019.

  6. Marsh-Ng ML, Burney DP, Garcia J. Surveillance of infections associated with intravenous catheters in dogs and cats in an intensive care unit. J Am Anim Hosp Assoc. 2007;43(1):13–20.

    Article  PubMed  Google Scholar 

  7. Lippert A, Fulton R Jr, Parr A. Nosocomial infection surveillance in a small animal intensive care unit. J Am Anim Hosp Assoc. 1988;24(6):627–36.

    Google Scholar 

  8. Mathews KA, Brooks MJ, Valliant AE. A prospective study of intravenous catheter contamination. J Vet Emerg Crit Care. 1996;6(1):33–43.

    Article  Google Scholar 

  9. Burrows CF. Inadequate skin preparation as a cause of intravenous catheter related infection in the dog. J Am Vet Med Assoc. 1982;180(7):747–9.

    CAS  PubMed  Google Scholar 

  10. Beal MW, Hughes D. Vascular access: theory and techniques in the small animal emergency patient. Clin Tech Small Anim Pract. 2000;15(2):101–9.

    Article  CAS  PubMed  Google Scholar 

  11. Palm Ü, Boemke W, Bayerl D, Schnoy N, Juhr NC, Reinhardt HW. Prevention of catheter-related infections by a new, catheter-restricted antibiotic filling technique. Lab Anim. 1991;25(2):142–52.

    Article  CAS  PubMed  Google Scholar 

  12. Safdar N, Maki DG. Inflammation at the insertion site is not predictive of catheter-related bloodstream infection with short-term, noncuffed central venous catheters. Crit Care Med. 2002;30(12):2632–5.

    Article  PubMed  Google Scholar 

  13. Bodmann K-F, Vogel F. Antimikrobielle Therapie der Sepsis. Chemotherapie J. 2001;2:43–55.

    Google Scholar 

  14. Garvey MS, Aucoin DP. Therapeutic strategies involving antimicrobial treatment of disseminated bacterial infection in small animals. J Am Vet Med Assoc. 1984;185:1185–9.

    CAS  PubMed  Google Scholar 

  15. Beukers AG, Zaheer R, Goji N, Amoako KK, Chaves AV, Ward MP, McAllister TA. Comparative genomics of Enterococcus spp. isolated from bovine feces. BMC Microbiol. 2017;17(1):1–18.

    Article  Google Scholar 

  16. Chadfield MS, Christensen JP, Juhl-Hansen J, Christensen H, Bisgaard M. Characterization of Enterococcus hirae outbreaks in broiler flocks demonstrating increased mortality because of septicemia and endocarditis and/or altered production parameters. Avian Dis. 2005;49(1):16–23.

    Article  CAS  PubMed  Google Scholar 

  17. Poeta P, Costa D, Rodrigues J, Torres C. Antimicrobial resistance and the mechanisms implicated in faecal enterococci from healthy humans, poultry and pets in Portugal. Int J Antimicrob Agents. 2006;27(2):131–7.

    Article  CAS  PubMed  Google Scholar 

  18. Devriese LA, Colque JIC, De Herdt P, Haesebrouck F. Identification and composition of the tonsillar and anal enterococcal and streptococcal flora of dogs and cats. J Appl Bacteriol. 1992;73(5):421–5.

    Article  CAS  PubMed  Google Scholar 

  19. Chan T, Wu M, Suk F, Chen C, Chen Y, Hou Y, Lien GS. -related acute pyelonephritis and cholangitis with bacteremia: an unusual infection in humans. The Kaohsiung J of Med Scie. 2012;28(2):111–4.

    Article  Google Scholar 

  20. Poyart C, Lambert T, Morand P, Abassade P, Quesne G, Baudouy Y, Trieu-Cuot P. Native Valve Endocarditis due to. J Clin Microbiol. 2002;40(7):2689–90.

    Article  PubMed  PubMed Central  Google Scholar 

  21. Sim JS, Kim HS, Oh KJ, Park MS, Jung EJ, Jung YJ, Kang DG, Seo SI, Ki WJ, Jang MK. Spontaneous bacterial peritonitis with Sepsis caused by. J Korean Med Sci. 2012;27(12):1598.

    Article  PubMed  PubMed Central  Google Scholar 

  22. Dicpinigaitis PV, De Aguirre M, Divito J. Enterococcushirae Bacteremia Associated with Acute Pancreatitis and Septic Shock. Case Reports in Infectious Diseases 2015, 2015:1–3.

  23. Bourafa N, Loucif L, Boutefnouchet N, Rolain JM. Enterococcus hirae, an unusual pathogen in humans causing urinary tract infection in a patient with benign prostatic hyperplasia: first case report in Algeria. New microbes and new infections. 2015;8:7–9.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  24. Blaseg NA, Hoover SE. Wound infection with Enterococcus hirae Associated with Cat Litter. Infect Dis Clin Pract. 2021;29(4):242–3.

    Article  Google Scholar 

  25. Vela AI, Fernández A, Moreno B, Casamayor A, Chacón G, Villa A, Comenge J, Fernández-Garayzábal JF. Isolation of. from suckling rabbits with diarrhoea The Veterinary Record. 2010;167(9):345.

    CAS  PubMed  Google Scholar 

  26. van Loon ACJ, Locquet LJN, Bosseler L, Mortier F, Paepe D, Smets PMY. Infective vegetative endocarditis of the mitral, aortic, and pulmonary valves due to Enterococcus hirae in a cat with a ventricular septal defect. J Vet Cardiol. 2020;30:69–76.

    Article  PubMed  Google Scholar 

  27. Lapointe JM, Higgins R, Barrette N, Milette S. Enteropathy with Ascending Cholangitis and Pancreatitis in a Kitten. Vet Pathol. 2000;37(3):282–4.

    Article  CAS  PubMed  Google Scholar 

  28. Nicklas JL, Moisan P, Stone MR, Gookin JL. In situ molecular diagnosis and histopathological characterization of Enteroadherent. Infect Pre-Weaning-Age Kittens J Clin Microbiol. 2010;48(8):2814–20.

    PubMed  Google Scholar 

  29. Ghosh A, Borst L, Stauffer SH, Suyemoto M, Moisan P, Zurek L, et al. Mortality in Kittens is Associated with a Shift in Ileum Mucosa-Associated Enterococci from. to Biofilm-Forming Enterococcus faecalis and Adherent Escherichia coli J Clin Microbiol. 2013;51(11):3567–78.

    PubMed  Google Scholar 

  30. Yousfi M, Touati A, Muggeo A, Mira B, Asma B, Brasme L, et al. Clonal dissemination of OXA-48-producing. isolates from companion animals in Algeria Journal of Global Antimicrobial Resistance. 2018;12:187–91.

    PubMed  Google Scholar 

  31. Sharif NM, Sreedevi B, Chaitanya RK, Sreenivasulu D. Beta-lactamase antimicrobial resistance in. and Enterobacter species isolated from healthy and diarrheic dogs in Andhra Pradesh India Vet World. 2017;10(8):950–4.

    CAS  Google Scholar 

  32. Mezzatesta ML, Gona F, Stefani S. Complex: clinical impact and emerging antibiotic resistance. Future Microbiol. 2012;7(7):887–902.

    Article  CAS  PubMed  Google Scholar 

  33. Kaye KS, Cosgrove S, Harris A, Eliopoulos GM, Carmeli Y. Risk factors for emergence of resistance to Broad-Spectrum Cephalosporins among. spp Antimicrob Agents Chemother. 2001;45(9):2628–30.

    Article  CAS  PubMed  Google Scholar 

  34. Gu CT, Li CY, Yang LJ, Huo GC et al. Enterobacterxiangfangensis sp. nov., isolated from Chinese traditional sourdough, and reclassification of Enterobactersacchari Zhu. 2013 as Kosakonia sacchari comb. nov. International Journal of Systematic and Evolutionary Microbiology 2014, 64(8):2650–6.

  35. Oshiro S, Tada T, Watanabe S, Tohya M, Hishinuma T, Uchida H, Kuwahara-Arai K, Mya S, Zan KN, Kirikae T, Tin HH. Emergence and spread of Carbapenem-Resistant and Aminoglycoside-Panresistant. Complex Isolates Coproducing NDM-Type Metallo-β-Lactamase and 16S rRNA Methylase in Myanmar mSphere. 2020;5(2):e00054–20.

    CAS  PubMed  Google Scholar 

  36. Peirano G, Matsumura Y, Adams MD, Bradford P, Motyl M, Chen L, Kreiswirth BN, Pitout JDD. Genomic epidemiology of global carbapenemase-producing. spp 2008–2014 Emerg Infect Dis. 2018;24(6):1010–9.

    PubMed  Google Scholar 

  37. Wu W, Wei L, Feng Y, Xie Y, Zong Z. Precise Species Identification by Whole-Genome Sequencing of Enterobacter Bloodstream Infection, China.Emerg Infect Dis 2021, Girlich27(1):161–9.

  38. Girlich D, Ouzani S, Emeraud C, Gauthier L, Bonnin RA, Le Sache N, Mokhtari M, Langlois I, Begasse C, Arangia N, Fournier S, Fortineau N, Naas T, Dortet L. Uncovering the novel Enterobacter cloacae complex species responsible for septic shock deaths in newborns: a cohort study. The Lancet Microbe. 2021;2(10):e536–44.

    Article  PubMed  Google Scholar 


    Article  Google Scholar 

  40. Yu Z, Peng C, Kwok L, Zhang H. The Bacterial Diversity of Spontaneously Fermented Dairy Products Collected in Northeast Asia. Foods 2021,10(10):2321.

  41. Daniels JB, Chen L, Grooters SV, Mollenkopf DF, Mathys DA, Pancholi P, Kreiswirth BN, Wittum TE. Complex sequence type 171 isolates expressing KPC-4 carbapenemase recovered from Canine Patients in Ohio. Antimicrob Agents Chemother. 2018;62(12):e01161–18.

    Article  PubMed  PubMed Central  Google Scholar 

  42. Dingle TC, Butler-Wu SM. MALDI-TOF Mass Spectrometry for Microorganism Identification. Clin Lab Med. 2013;33(3):589–609.

    Article  PubMed  Google Scholar 

Download references


Not applicable.


No funding were received.

Author information

Authors and Affiliations



RS and SP analyzed and interpreted the patient data and were major contributors in writing the manuscript. MG and AP contributed to writing and reviewing the clinical aspect of the case report. EE and FS contributed to collecting data and reviewing the manuscript. All authors read and approved the final manuscript.

Corresponding author

Correspondence to Raffaele Scarpellini.

Ethics declarations

Ethics approval and consent to participate

Written informed approval was obtained from both owners.

Consent for publication

Not applicable.

Competing Interest

The authors declare that they have no competing interests.

Additional information

Publisher’s Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit The Creative Commons Public Domain Dedication waiver ( applies to the data made available in this article, unless otherwise stated in a credit line to the data.

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Scarpellini, R., Giunti, M., Pontiero, A. et al. Two cases of bloodstream infections associated with opportunistic bacterial species (Enterococcus hirae and Enterobacter xiangfangensis) in companion animals. BMC Vet Res 19, 63 (2023).

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: