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Inducing Meningococcal Meningitis Serogroup C in Mice via Intracisternal Delivery
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MENINGITIS IN AN INFANT DUE TO A HITHERTO UNDESCRIBED ORGANISM, MICROCOCCUS FLORENS

W C Davison1, A S Davison, M K Miller

  • 1Department of Pediatrics and the Department of Pathology of the Johns Hopkins University, Baltimore.

The Journal of Experimental Medicine
|October 30, 2009
PubMed

Insights

Micrococcus florens is pathogenic in animal models, causing septicemia and meningitis. It is distinct from meningococcus, despite morphological similarities, based on biological and agglutination tests.

Area of Science:

  • Microbiology
  • Pathogen Discovery
  • Bacteriology

Background:

  • The study investigates a Gram-negative micrococcus, Micrococcus florens.
  • Morphological similarity to meningococcus necessitates further differentiation.
  • Limited literature exists on Gram-negative micrococci with specific growth and fermentation profiles.

Purpose of the Study:

  • To determine the pathogenicity of Micrococcus florens in animal models.
  • To differentiate Micrococcus florens from morphologically similar bacteria, such as meningococcus.
  • To characterize the unique biological and biochemical properties of Micrococcus florens.

Main Methods:

  • Virulence tests were conducted on mice, rabbits, and monkeys (Macacus rhesus).
  • Biological reactions and agglutination tests were employed for bacterial characterization.
  • Literature review was performed to compare findings with existing descriptions.

Main Results:

  • Micrococcus florens demonstrated pathogenicity, causing septicemia in mice, rabbits, and monkeys.
  • Purulent meningitis was observed in rabbits and monkeys infected with Micrococcus florens.
  • The organism is morphologically similar to meningococcus but distinct based on biological and agglutination tests.
  • Micrococcus florens is a Gram-negative micrococcus that grows luxuriantly on various media, produces no pigment, and ferments arabinose, dextrose, and galactose.

Conclusions:

  • Micrococcus florens is a distinct bacterial species pathogenic to multiple animal models.
  • The organism's unique biochemical profile differentiates it from known bacteria, including meningococcus.
  • Further research is warranted to understand the full clinical and epidemiological significance of Micrococcus florens.

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