Related Experiment Video

Updated: Aug 30, 2026

Using Bioluminescent Imaging to Investigate Synergism Between Streptococcus pneumoniae and Influenza A Virus in Infant Mice
10:47

Using Bioluminescent Imaging to Investigate Synergism Between Streptococcus pneumoniae and Influenza A Virus in Infant Mice

Published on: April 14, 2011

[A case of Paenibacillus polymyxa bacteremia in a patient with cerebral infarction]

Yoshiyuki Nasu1, Yoshitomo Nosaka, Yoshihito Otsuka

  • 1Department of Clinical Laboratory, Noheji-municipal Hospital.

Kansenshogaku Zasshi. the Journal of the Japanese Association for Infectious Diseases
|November 12, 2003
PubMed

Insights

A rare case of Paenibacillus polymyxa bacteremia occurred in an elderly patient with cerebral infarction. Daily gardening activities were identified as a potential risk factor for this gram-positive spore bacillus infection.

Area of Science:

  • Medical Microbiology
  • Infectious Diseases
  • Clinical Case Study

Background:

  • Bacteremia, the presence of bacteria in the bloodstream, can lead to severe complications.
  • Paenibacillus polymyxa is a gram-positive spore-forming bacterium found in soil and plant matter.
  • Cerebral infarction, or stroke, is a significant risk factor for infections due to impaired immune function.

Observation:

  • A 93-year-old female with cerebral infarction developed a fever (38.2°C) on the fourth day of hospitalization.
  • Blood cultures revealed a gram-positive spore bacillus.
  • The patient had a daily habit of gardening, involving potential hand injuries.

Findings:

  • 16S rRNA gene sequencing identified the bacterium as Paenibacillus polymyxa with 99.26% similarity.
  • Biochemical tests using API 20E and API 50CH further confirmed the identification as Paenibacillus polymyxa.
  • The patient's gardening habit was considered a likely source of inoculation, leading to bacteremia.

Implications:

  • This case highlights Paenibacillus polymyxa as a potential pathogen in immunocompromised individuals.
  • Occupational or recreational activities involving soil contact may increase the risk of Paenibacillus polymyxa infections.
  • Awareness of environmental sources of infection is crucial for preventing bacteremia in vulnerable patients.

Related Concept Videos

Bacterial Meningitis I: Introduction01:22

Bacterial Meningitis I: Introduction

Bacterial meningitis is a severe, life-threatening inflammation of the meninges, particularly the pia mater and arachnoid mater, affecting the subarachnoid space, ventricles, and cerebrospinal fluid (CSF). If untreated, it can lead to significant neurological complications or death.Causative AgentsCommon pathogens vary with age and immune status. In adults, major organisms include Streptococcus pneumoniae, Neisseria meningitidis, and Haemophilus influenzae. Streptococcus agalactiae (group B...
Bacterial Meningitis01:24

Bacterial Meningitis

Bacterial meningitis is a severe infectious disease involving inflammation of the meninges, the protective membranes surrounding the brain and spinal cord. It occurs when pathogenic bacteria cross the blood–brain barrier and enter the cerebrospinal fluid. Common causative organisms include Neisseria meningitidis, Streptococcus pneumoniae, Haemophilus influenzae type b, Listeria monocytogenes, and Escherichia coli K1. The exact route of entry varies by pathogen and host condition.Routes of Entry...
Brain Abscess l: Introduction01:26

Brain Abscess l: Introduction

A brain abscess is a focal, intracerebral infection characterized by a localized collection of pus within the brain parenchyma, resulting from microbial invasion and the body’s inflammatory response. It progresses through stages: early and late cerebritis, followed by early and late capsule formation, reflecting tissue destruction, immune response, and eventual encapsulation.Etiology and PathogenesisCausative organisms vary with source and host factors, often involving polymicrobial infections,...
Pneumonia I: Introduction01:29

Pneumonia I: Introduction

Pneumonia is an infection of the lower respiratory tract that leads to inflammation of the lung parenchyma, often resulting in the accumulation of inflammatory exudate in the alveoli and airways. Unlike the watery, low-protein fluid exudate in pulmonary edema, the exudate in this case is a thick fluid rich in immune cells, proteins, and debris produced during infection and inflammation.This impairs gas exchange and can lead to consolidation of lung tissue. The infection may be caused by a...
Pneumonia I: Introduction01:30

Pneumonia I: Introduction

Pneumonia is an acute respiratory infection that targets the lungs, specifically the alveoli. These tiny air sacs, essential for oxygen exchange, become engorged with pus and fluid, severely hindering breathing, decreasing oxygen absorption, and causing significant pain and discomfort during respiration.
Risk Factors
Various factors influence the likelihood of developing pneumonia. Age plays a crucial role, with infants, children under two, and individuals over 65 at increased risk due to their...
Bacterial Meningitis II: Pathophysiology01:26

Bacterial Meningitis II: Pathophysiology

Bacterial meningitis typically begins when pathogens such as Neisseria meningitidis and Streptococcus pneumoniae colonize the nasopharynx and invade the bloodstream. This process is facilitated by bacterial virulence factors, such as polysaccharide capsules, which resist phagocytosis and complement-mediated killing. Less commonly, bacteria reach the central nervous system via contiguous spread from infections like otitis media or sinusitis, through congenital or acquired dural defects, or...