Basics for Clinical Microbiology Flashcards
What does bacteremia mean?
Bacteria in the blood
What does septicemia mean?
Replicating bacteria in the blood
What is pathogenicity?
The ability to cause disease by evading or overcoming the host defenses
What is virulence?
The extent to which the microorganism is pathogenic
What are virulence factors?
Molecules or strategies produced by pathogens that actively contribute to their pathogenicity either by evading immunity or damaging host systems
What is tropism?
The affinity that an organism has for certain cells or tissues
What are the determinants of tropism?
Distribution of cell receptors for microbes
Accessibility of correct host cell types
Requirement for appropriate cellular elements that will allow the microbe to grow
Physical and innate defenses at the site of infection
What are host factors influencing the occurrence, course, or severity of disease?
Age at onset of the disease
Sex
Race
Genetic factors controlling the immune system
Preexisting level of innate and adaptive immunity
Behavior and lifestyle
Dual infection or superinfection
Preexisting chronic conditions or pregnancy
Nutritional status
Psychological status
What is conjugation?
Transferral of plasmids containing genes for virulence attributes or antibiotic resistance
Sex pilus allows plasmid to transfer from donor to recipient
What is transduction?
Acquisition of genes for toxin production - bacteriophage
What is transformation?
Acquiring gene for toxin, capsule production, or other things - take up DNA from the environment
