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Super-resolution Imaging of Proteus mirabilis Biofilm by Expansion Microscopy
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Characteristics of bacteremia caused by extended-spectrum beta-lactamase-producing Proteus mirabilis

Yoko Kurihara1, Shigemi Hitomi, Tsuyoshi Oishi

  • 1Department of Infectious Diseases, University of Tsukuba Hospital, 2-1-1 Amakubo, Tsukuba, Ibaraki, 305-8576, Japan.

Journal of Infection and Chemotherapy : Official Journal of the Japan Society of Chemotherapy
|February 2, 2013
PubMed

Insights

Extended-spectrum beta-lactamase (ESBL)-producing Proteus mirabilis bacteremia is linked to hospital onset and prior antibiotic use. While ESBL strains delay appropriate treatment, they do not appear to increase 30-day mortality.

Area of Science:

  • Medical Microbiology
  • Infectious Diseases
  • Antimicrobial Resistance

Background:

  • Proteus mirabilis is a frequent human pathogen.
  • Bacteremia caused by P. mirabilis, particularly strains producing extended-spectrum beta-lactamase (ESBL), is understudied.
  • ESBL-producing bacteria pose a significant challenge due to their resistance to common antibiotics.

Purpose of the Study:

  • To investigate the clinical characteristics of P. mirabilis bacteremia.
  • To compare cases involving ESBL-producing strains versus non-producing strains.
  • To identify risk factors and outcomes associated with ESBL-producing P. mirabilis bacteremia.

Main Methods:

  • Retrospective analysis of 64 P. mirabilis bacteremia cases in Japan (2001-2010).
  • Comparison of clinical data between ESBL-producing (n=13) and non-producing (n=51) strains.
  • Genetic analysis of ESBL-producing strains to assess diversity.

Main Results:

  • ESBL-producing strains were significantly associated with hospital onset, hemodialysis, and recent antibiotic use (penicillin, cephalosporin, fluoroquinolone).
  • Isolation of ESBL-producing strains correlated with delayed appropriate antibiotic therapy on days 1 and 4.
  • No significant association was found between ESBL-producing strains and 30-day mortality.

Conclusions:

  • P. mirabilis bacteremia caused by ESBL-producing strains is associated with specific patient risk factors and healthcare exposures.
  • The presence of ESBL in P. mirabilis bacteremia leads to delays in effective antimicrobial treatment.
  • Despite treatment delays, ESBL production in P. mirabilis bacteremia does not appear to significantly impact short-term mortality.

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