Bacteremia caused by Elizabethkingia meningoseptica in a mechanically ventilated patient successfully treated with imipenem-cilastatin and ciprofloxacin

Changhua, February 14, 2017

Dear editor

Elizabethkingia meningoseptica is ubiquitous in soil and water as well as in hospital environments^1,2,3. Thus, nosocomial outbreaks of E. meningoseptica can result from exposure to contaminated water sources or medical devices². Due to the therapeutic challenge resulting from multi-drug resistance, recognition and treatment of E. meningoseptica is of paramount importance for clinicians^2,3. We report a case of bacteremia due to a multi-drug resistant E. meningoseptica in a patient who required assisted ventilation due to respiratory failure.

A 62-year-old male, who had had a history of oral cancer with operation and concurrent chemoradiotherapy, diabetes mellitus, bilateral vocal palsy, upper airway obstruction followed by tracheostomy and chronic obstructive pulmonary disease, developed cough with shortness of breath prior to admission. He was admitted to the intensive care ward because of impending respiratory failure. Ventilation support with Evita 4 (Dräger, Lubeck, Germany) was used, and he was transferred to the respiratory care center (RCC) for weaning twenty-one days later, because of fluctuations in his respiratory condition associated with underlying pulmonary problems. A new fever episode appeared on the 11^th day after transfer to RCC (Figure 1). The lungs showed crackles on the right side. Laboratory analyses revealed a white blood cell count of 10,800 cells/ mm³. The serum creatinine level was 2.3 mg/dL. The chest X-ray showed a new pneumonic patch over the left lower lobe. E. meningoseptica (2/2 sets) was identified by using matrix-assisted laser desorption ionization-time of flight mass spectrometry (bioMerieux, Hazlewood, Mo.). An antimicrobial drug susceptibility test⁴ was conducted for E. meningoseptica by using the bioMérieux VITEK 2 system (bioMerieux, Hazlewood, MO.), and the minimum inhibitory concentration (MIC) was measured for each of the following antimicrobial drugs: piperacillin-tazobactam, cefotaxime, flomoxef, ceftazidime, cefepime, cefoperazone, amikacin, gentamicin, ciprofloxacin, levofloxacin, imipenem-cilastatin, meropenem, trimethoprim-sulfamethoxazole, doxycycline and colistin (Table 1). In addition, MIC results determined by the Epsilometer test (AB Biodisk, Sweden system) were: ciprofloxacin ≧4 μg/mL; levofloxacin ≧8 μg/mL; imipenem-cilastatin ≧16 μg/mL; meropenem ≧16 μg/mL; trimethoprim-sulfamethoxazole ≧4/ 76 μg/mL; and vancomycin ≧16 μg/mL. The patient received a combination of intravenous ciprofloxacin (200 mg every 12 hours) and imipenem-cilastatin (250 mg every 6 hours). His condition stabilized gradually and the follow-up chest X-ray showed improvement. Due to difficulty in weaning, he was transferred to a respiratory care ward after 42 days of hospitalization at RCC. No outbreak of E. meningoseptica infection was reported during the period of hospitalization at RCC. The follow-up of microbiological analyses for this patient did not show E. meningoseptica infection.

Figure 1
Timeline of the Elizabethkingia meningoseptica infection, serial chest X-ray images and serial antibiotics history

Table 1
Susceptibilities of this isolate to the antimicrobial agents

	E-test 3	VITEK 24	MIC interpretation criteria (μg/mL)
Antimicrobial agent 1	This isolate		S	I	R
Amikacin		≧64	≤ 16	32	≥ 64
Cefepime		≧32	≤ 8	16	≥ 32
Cefoperazone		≧64	≤ 16	32	≥ 64
Cefotaxime		≧32	≤ 8	16-32	≥ 32
Flomoxef		≧64	(pending)
Ceftazidime		≧32	≤ 8	16	≥ 32
Ciprofloxacin	≧4	≧4	≤ 1	2	≥ 4
Colistin		≧16	≤ 2	4	≥ 8
Doxycycline		≧16	≤ 4	8	≥ 16
Gentamicin		≧16	≤ 4	8	≥ 16
Imipenem	≧16	≧16	≤ 4	8	≥ 16
Levofloxacin	≧8	≧8	≤ 2	4	≥ 8
Meropenem		≧16	≤ 4	8	≥ 16
Minocycline		≧16	≤ 4	8	≥ 16
Piperacillin/tazobactam		≧128	≤ 16/4	32/4-64/4	≥ 32/4
Trimethoprim/sulfamethoxazole	≧4/76	≧4/76	≤ 2/38	-	≥ 4/76
Vancomycin2	≥ 16		≤ 2	4-8	≥ 16

• Notes:1The Clinical and Laboratory Standards Institute (CLSI) minimum inhibitory concentration (MIC) breakpoints for non-Enterobacteriaceae were applied for all antimicrobial agents except for vancomycin and flomoxef [Clinical and Laboratory Standards Institute. 2016. M100-S26: performance standards for antimicrobial susceptibility testing, 26^th informational supplement. CLSI, Wayne, PA.]. 2The CLSI MIC breakpoint for Staphylococcus spp. was applied to vancomycin. 3Antimicrobial drug susceptibility test was conducted by using the Epsilometer test (AB Biodisk, Sweden system). 4Antimicrobial drug susceptibility test was conducted by using the bioMérieux VITEK 2 system (bioMerieux, Hazlewood, MO.). Abbreviation: CLSI: Clinical and Laboratory Standards Institute; I: intermediate; MIC: minimal inhibitory concentration; S: susceptible; R: resistant.

The appropriate choice of antibiotics for treatment of E. meningoseptica infection is difficult because optimal antimicrobial guidelines remain to be established^2,3. Herein, the antimicrobial drug susceptibility test of this E. meningoseptica showed resistance to all the antibiotics, including trimethoprim-sulfamethoxazole and vancomycin⁵. However, the bacteremia caused by E. meningoseptica was successfully treated in this case with a two-week administration of imipenem-cilastatin and ciprofloxacin. In terms of generalization, this case description is limited by the restricted number of clinical studies in the literature^2,3, the lack of minimum inhibitory concentration breakpoints of antimicrobial agents to E. meningoseptica⁴, and the paucity of 16S rRNA sequencing data due to the inability to perform a reliable 16S rRNA sequencing analysis without a valid positive control⁶.

We suggest a combination therapy as an alternative for treatment of multi-drug resistant E. meningoseptica infection and undertaking active surveillance of E. meningoseptica infections because E. meningoseptica outbreaks could subsequently result from exposure to contaminated water sources or medical devices.

ACKNOWLEDGEMENTS

The authors thank the Changhua Christian Hospital for providing us with the clinical Elizabethkingia meningoseptica isolate. The authors thank Ru-Hua Hsiu for the handling the microbiological identification, as well as Chin-Hsin Li for handling the assisted ventilation. The authors thank the Changhua Christian Hospital for the grant support. All authors thank the assistants of the Clinical Microbiology Laboratory of the Changhua Christian Hospital for their assistance in data collection. This research project would not have been possible without the support of many people. The authors wish to express their gratitude to the staffs of Division of Infectious Diseases, Division of Chest Medicine, and Division of Critical Care of Changhua Christian Hospital who were very helpful and conducted the patient’s care.

REFERENCES

• ¹
  Hsu MS, Liao CH, Huang YT, Liu CY, Yang CJ, Kao KL, et al. Clinical features, antimicrobial susceptibilities, and outcomes of Elizabethkingia meningoseptica (Chryseobacterium meningosepticum) bacteremia at a medical center in Taiwan, 1999-2006. Eur J Clin Microbiol Infect Dis. 2011;30:1271-8.
• ²
  Barlam TF, Kasper DL. Infections due to the HACEK group and miscellaneous Gram-Negative bacteria. In: Kasper DL, Hauser SL, Jameson JL, Fauci AS, Longo DL, Loscalzo J, editors. Harrison’s Principles of internal medicine, 19th ed. New York: McGraw-Hill Education; 2015.
• ³
  Steinberg JP, del Rio C. Other Gram-Negative bacilli. In: Mandell GL, Bennet JE, Dolin R, editors. Mandell, Douglas and Bennet’s Principles and practice of infectious diseases. 7th ed. Edinburg: Churchill Livingstone; 2010.
• ⁴
  Clinical and Laboratory Standards Institute. M100-S26: performance standards for antimicrobial susceptibility testing, 26^th informational supplement. Wayne, PA: CLSI; 2016.
• ⁵
  Fraser SL, Jorgensen JH. Reappraisal of the antimicrobial susceptibilities of Chryseobacterium and Flavobacterium species and methods for reliable susceptibility testing. Antimicrob Agents Chemother. 1997;41:2738-41.
• ⁶
  Han MS, Kim H, Lee Y, Kim M, Ku NS, Choi JY, et al. Relative prevalence and antimicrobial susceptibility of clinical isolates of Elizabethkingia species based on 16S rRNA gene sequencing. J Clin Microbiol. 2016;55:274-80.

• RESEARCH FUNDING/SUPPORT. The present work was partially supported by a grant from the Changhua Christian Hospital (grant 105-CCH-IPR-001).

Publication Dates

• Publication in this collection
  2017

History

• Received
  14 Feb 2017
• Accepted
  10 Apr 2017