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First case of bloodstream infection caused by NDM-positive Escherichia hermannii

Abstract

Background

Escherichia hermannii (E. hermanni) is always accompanied by other bacterial infections in humans. In previous reports, most E. hermannii-related infections were caused by sensitive strains. Here, for the first time, we report the case of a patient with New Delhi metallo-β-lactamase (NDM)-positive E. hermannii bloodstream infection.

Case presentation

The patient was a 70-year-old male admitted to our hospital due to a 4-day fever, with a history of malignant tumor, liver cirrhosis, and chronic obstructive pulmonary disease. After admission, his blood culture tested positive for E. hermannii. The drug resistance analysis showed positive for NDM resistance, with susceptibility to aztreonam, levofloxacin, and amikacin. The blood culture turned negative after 8 days of aztreonam treatment. The patient’s symptoms improved, and he was discharged after 14 days of hospitalization.

Conclusions

This is the first report of a bloodstream infection caused by an NDM-positive E. hermannii strain. The anti-infection regimen used in this case provides a new reference regimen for clinical practice.

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Background

Escherichia hermannii (E. hermannii) is a gram-negative and facultative anaerobic bacterium first reported in 1982. It is a member of the Enterobacteriaceae family and was reclassified as a distinct species within the Escherichia genus based on the biochemical and genomic differences from Escherichia coli [1]. In recent years, E. hermannii has been found as a single causative agent of infection [2,3,4]. Most E. hermannii strains are antibiotic sensitive, while a few are resistant to antibacterial drugs such as penicillins, cephalosporins, quinolones and carbapenems [5, 6]. In this study, we report a bloodstream infection case caused by a New Delhi metallo-β-lactamase (NDM)-positive E. hermannii strain. This strain was resistant to penicillin, cephalosporins, β-lactamase inhibitor combinations, and carbapenems. The patient improved after aztreonam treatment. Practitioners must pay close attention to infections caused by NDM positive E. hermannii, particularly for immunodeficient populations.

Case presentation

A 70-year-old male patient was admitted to Affiliated Dongyang Hospital of Wenzhou Medical University on July 23, 2022, after experiencing chills and fever for 4 days. The physical examination upon admission revealed the following vital signs: temperature 39.5 °C, heart rate 82 beats/min, respiratory rate 20 beats/min, blood pressure 149/99 mmHg. The abdomen was distended without tenderness and rebound pain and with positive shifting dullness.

The patient had a history of hypertension, hepatitis B cirrhosis, and chronic obstructive pulmonary disease. Six months before admission, the patient underwent total gastrectomy due to a gastric malignant tumor diagnosis with a secondary malignant tumor in the abdominal cavity, followed by two chemotherapies after surgery. In addition, he presented with obstructive hydronephrosis 23 days before admission, and a double J catheter was placed in another hospital. He was then hospitalized in our facilities due to anuria 19 days before admission, where he underwent a nephrostomy for both kidneys and was discharged after hemodialysis treatment.

Laboratory examinations at admission

A blood sample was collected immediately after hospitalization and sent for bacterial culture within 2 h. After incubation on a blood-agar plate at 37℃ for 48 h, only one bacterial morphology type formed (Fig. 1A). The species was identified as E. hermannii by mass spectrometry. The drug susceptibility test was performed by using AST-335 card and AST334 card on a VITEK® 2 Compact system (VITEK, France) and minimum inhibitory concentration was read automatically (Table 1). This strain was resistant to penicillin, cephalosporins, β-lactamase inhibitor combinations (cefoperazone /sulbactam, piperacillin/ tazobactam, amoxicillin /clavulanate and ticarcillin /clavulanate), carbapenems, but sensitive to aztreonam, tigecycline, levofloxacin, and amikacin. Gold immunolabeling test (Mountainriver, Beijing, China) showed that this strain was positive for NDM (Fig. 1B), negative for KPC, O48 and VIM. The blood routine test showed several abnormal indexes: 9.19 × 10^9/L white blood cells (WBCs), 94.4% neutrophils, 79 g/L hemoglobin, 206.33 mg/L hypersensitive C-reactive protein (CRP), 2.96 ng/ml procalcitonin (PCT). A positive WBCs result and abnormal urea (10.1 mmol/L) and creatinine (156 µmol/L) levels were found in urine. An abdominocentesis was performed 3 days after admission showing turbid yellow ascites. The Rivalta test was positive, revealing 1.195 × 10^9/L nucleated cells, where multinucleated cells accounted for 74.3% and mononuclear for 25.7%. Ascites and urine were both negative in culture examinations.

Fig. 1
figure 1

Identification of an NDM-positive Escherichia hermannii. (A) The colony morphology of Escherichia hermannii on the blood culture plate; (B) The enzymes for carbapenem resistance by gold immunolabeling test

Table 1 The minimum inhibitory concentrations of an NDM-positive Escherichia hermannii

Diagnosis and treatments

On the first day after admission, the patient was treated with 2 g intravenous cefoperazone-sulbactam every 12 h and acetaminophen for defervescence and fluid replacement. On the 3rd day after admission, the patient’s blood inflammatory indicators were not improving (PCT 3.47 ng/ml; CRP 200.83 mg/L). According to the species identification and drug susceptibility results, the antibiotic treatment was switched to 1 g intravenous aztreonam every 8 h on the 4th day after admission. Consequently, blood inflammation indicators gradually decreased (Fig. 2), and on the 8th day of treatment, the blood culture turned negative. The patient’s symptoms improved, and he was discharged after 14 days of hospitalization.

Fig. 2
figure 2

The inflammatory indexes of this case infected by NDM-positive Escherichia hermannii during hospitalization

Discussion and conclusions

E. hermannii was initially proposed as a new species by Brenner in 1982. It has been successfully isolated from several infection sites, including wounds [7], peritonitis [8], conjunctivitis [9], blood [10], cerebrospinal fluid [11], and urine [12]. The most common infection sites comprise bloodstream, urinary tract, and central nervous system infections [5]. In this report, we described a case with bloodstream infection caused by E. hermanii. Recently, previous studies have reported E. hermannii as the only causative agent, including patients with open tibial shaft fractures [2], uremia requiring long-term hemodialysis [3], and after peripherally inserted central catheter placement [4]. The patient had underlying diseases such as a malignant tumor, hepatitis B cirrhosis, and chronic obstructive pulmonary disease, indicating he was immunocompromised. Moreover, the patient was submitted to ureteral catheter placement and nephrostomy, including both kidneys, within one month before admission, which increased the risk of E. hermannii infection. No other bacterial or fungal growth was detected in the blood culture, with negative ascites and urine cultures. Therefore, E. hermannii was the only pathogen causing the bloodstream infection.

NDM resistance was initially identified in 2009 in Klebsiella pneumoniae isolated from an Indian-Swedish patient’s urine after a urinary tract infection in New Delhi, India [13]. Since this first isolation, NDM-resistant strains have been isolated for Acinetobacter baumannii, Escherichia coli, Salmonella, and other bacteria [14,15,16]. Our case is the first report on a bloodstream infection caused by NDM-positive E. hermannii.

Antibiotic selection for infectious disease treatment is primarily based on drug susceptibility results. Several previous reports show that E. hermannii is sensitive to most antibacterial drugs [5, 17]. However, a previous case by Sood et al. [6] detailed a bloodstream infection caused by E. hermannii in a 2-day-old infant. The strain was resistant to penicillin, cephalosporins, and carbapenems and sensitive to polymyxin and tigecycline. The patient recovered after 2 weeks of combined anti-infection treatment with polymyxin and amikacin. The NDM-positive E. hermannii strain in this work was resistant to penicillin, cephalosporins, β-lactamase inhibitor combinations, and carbapenems, but sensitive to aztreonam, levofloxacin, amikacin, and tigecycline. Since there was no previous experience for NDM-positive E. hermannii infection therapy, we decided to treat with aztreonam according to in vitro drug susceptibility test results. After 8 days of treatment, the blood culture turned negative and inflammatory index descreased, and after 14 days, the patient recovered from the infection and was discharged.

The patient was admitted to the hospital again 11 days after discharge due to other symptoms. Although his family members decided to discontinue treatment because of the patient’s cancer terminal stage, the treatment of E. hermannii bloodstream infection was successful. This is the first case with effective treatment for an NDM-positive E. hermannii infection, providing insight into optional solutions for the treatment of similar future conditions.

Bloodstream infections caused by E. hermannii are clinically rare and usually present in patients with underlying immunodeficiency diseases. Most of them are caused by susceptible strains. This is the first report of a bloodstream infection caused by an NDM-positive E. hermannii strain. We formulated a specific antibacterial drug treatment plan based on in vitro drug susceptibility test results. The anti-infection regimen used in this case provides a new reference regimen for clinical practice.

Data Availability

The datasets used during the current study are available from the corresponding author on reasonable request.

Abbreviations

E. hermannii :

Escherichia hermannii

NDM:

New Delhi metallo-β-lactamase

WBCs:

White blood cells

References

  1. Brenner DJ, Davis BR, Steigerwalt AG, Riddle CF, McWhorter AC, Allen SD, et al. Atypical biogroups of Escherichia coli found in clinical specimens and description of Escherichia hermannii sp. nov. J Clin Microbiol. 1982;15(4):703–13. https://doi.org/10.1128/jcm.15.4.703-713.1982.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  2. Compton J, Wynn M, Willey MC, Sekar P. Escherichia hermannii as the sole cause of osteomyelitis in a patient with an open tibial shaft fracture. BMJ Case Rep. 2019;12(11). https://doi.org/10.1136/bcr-2019-231206.

  3. Choudhury S, Seet C. Escherichia hermannii bloodstream infection in a long-term haemodialysis patient. Pathology. 2013;45(5):531. https://doi.org/10.1097/PAT.0b013e3283633fd7.

    Article  PubMed  Google Scholar 

  4. Sedlock C, Tokarczyk M, Sternlieb M, Flomenberg P. PICC-associated infection with Escherichia hermannii: a case report and review of the literature. IDCases. 2018;13:4. https://doi.org/10.1016/j.idcr.2018.e00444.

    Article  PubMed  PubMed Central  Google Scholar 

  5. Ioannou P. Escherichia hermannii Infections in humans: a systematic review. Trop Med Infect Dis. 2019;4(1). https://doi.org/10.3390/tropicalmed4010017.

  6. Sood S, Hemrajani SK. Blood Stream infection by Escherchia hermannii in a neonate. J Clin Diagn Res. 2016;10(8):Dd01–2. https://doi.org/10.7860/jcdr/2016/15906.8304.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  7. Pien FD, Shrum S, Swenson JM, Hill BC, Thornsberry C, Farmer JJ 3. Colonization of human wounds by Escherichia vulneris and Escherichia hermannii. J Clin Microbiol. 1985;22(2):283–5. https://doi.org/10.1128/jcm.22.2.283-285.1985.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  8. Ginsberg HG, Daum RS. Escherichia hermannii sepsis with duodenal perforation in a neonate. Pediatr Infect Dis J. 1987;6(3):300–2.

    Article  CAS  PubMed  Google Scholar 

  9. Poulou A, Dimitroulia E, Markou F, Tsakris A. Escherichia hermannii as the sole isolate from a patient with purulent conjunctivitis. J Clin Microbiol. 2008;46(11):3848–9. https://doi.org/10.1128/jcm.01119-08.

    Article  PubMed  PubMed Central  Google Scholar 

  10. Haasdijk RA, van Ingen J. Escherichia hermannii as the sole pathogen in urosepsis: case report. New Microbes New Infect. 2018;21:100–1. https://doi.org/10.1016/j.nmni.2017.11.005.

    Article  CAS  PubMed  Google Scholar 

  11. Dahl KM, Barry J, DeBiasi RL. Escherichia hermannii infection of a cephalohematoma: case report, review of the literature, and description of a novel invasive pathogen. Clin Infect Dis. 2002;35(9). https://doi.org/10.1086/342304. e96-8.

  12. Popescu GA, Daha I, Popescu C, Mitache E. Staphylococcus aureus and Escherichia hermanii in diabetes patient. Emerg Infect Dis, 2004. 10(7): p. 1335-7.doi: https://doi.org/10.3201/eid1007.030567.

  13. Yong D, Toleman MA, Giske CG, Cho HS, Sundman K, Lee K, et al. Characterization of a new metallo-beta-lactamase gene, blaNDM-1, and a novel erythromycin esterase gene carried on a unique genetic structure in Klebsiella pneumoniae sequence type 14 from India. Antimicrob Agents Chemother. 2009;53(12):5046–54. https://doi.org/10.1128/aac.00774-09.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  14. Boulanger A, Naas T, Fortineau N, Figueiredo S, Nordmann P. NDM-1-producing Acinetobacter baumannii from Algeria. Antimicrob Agents Chemother. 2012;56(4):2214–5. https://doi.org/10.1128/aac.05653-11.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  15. Chibabhai V, Nana T, Bosman N, Thomas T, Lowman W. Were all carbapenemases created equal? Treatment of NDM-producing extensively drug-resistant Enterobacteriaceae: a case report and literature review. Infection. 2018;46(1):1–13. https://doi.org/10.1007/s15010-017-1070-8.

    Article  PubMed  Google Scholar 

  16. Octavia S, Chew KL, Chew KL, Lin RTP, Teo JWP. Multidrug-resistant Salmonella enterica serovar London carrying bla(NDM-1) encoding plasmid from Singapore. Clin Microbiol Infect. 2020;26(7):963–6. https://doi.org/10.1016/j.cmi.2020.01.033.

    Article  CAS  PubMed  Google Scholar 

  17. Beauchef-Havard A, Arlet G, Gautier V, Labia R, Grimont P, Philippon A. Molecular and biochemical characterization of a novel class a beta-lactamase (HER-1) from Escherichia hermannii. Antimicrob Agents Chemother. 2003;47(8):2669–73. https://doi.org/10.1128/aac.47.8.2669-2673.2003.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

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Authors

Contributions

Lu B and Shi Y designed the study, Liu C and Jin C collected data. Zhou Y and Wang B participated in software performance, data correction and draft writing. Lu B and Pan X mainly contributed to study conception, design and manuscript writing. All the authors reviewed the final version of the manuscript and agreed to its publication.

Corresponding authors

Correspondence to Yunzhen Shi or Yangxiao Zhou.

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The authors declare no competing interests.

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Informed consent to participate in this case study and to publish the findings was obtained from the patient. This case study was reviewed and approved by the Ethics Committee and Institutional Review Board of Dongyang People’s Hospital (2022-YX-302).

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Lu, B., Wang, B., Pan, X. et al. First case of bloodstream infection caused by NDM-positive Escherichia hermannii. BMC Infect Dis 23, 355 (2023). https://doi.org/10.1186/s12879-023-08336-3

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