Concepts in Infection Flashcards
What is Empiric Management?
An educated guess on how to manage a patient based on the their clinical case
What is a Pathogen?
This is ANY microorganism that has the potential to cause disease
What is Virulence?
The ability/likelihood of a pathogen to cause disease
What is the Prodromal Period?
The period of minor illness preceding the point at which becomes more unwell e.g. in Shingles, the Prodromal Period is a burning pain which precedes the blisters
What is the Convalescing Period?
The period where the patient starts to recover from illness
What is the Difference between Aerobes and Anaerobes?
Aerobes grow in oxygen-rich environments whilst anaerobes grow in oxygen-void environments.
Which Aerobic Streptococcus Group is Alpha Haemolytic?
What is Alpha Haemolysis?
Strep. Viridans
Partial Lysis of RBCs (green stain on blood agar)
Which Aerobic Streptococcus Group is Beta Haemolytic?
What is Beta Haemolysis?
Strep. Pyogenes (Group A)
Group B Strep.
Complete Lysis of RBCs (bright white/gold stain on blood agar)
Which Aerobic Streptococcus Group is Gamma Haemolytic?
What is Gamma Haemolysis?
Enterococcus Group
No Lysis of RBCs (no stain but bacterial presence visible on blood agar)
How are Gram Negatives tested for in the lab?
Gram stain testing
They are tested based on their nutritional requirements for growth e.g. Lactose Fermenting
What Agar is used to grow Lactose Fermenting bacteria?
Give an example of a bacteria
McConkey Agar, which turns pink.
E.coli 0157
What further/additional testing can be done to aid identification of certain bacteria?
(E.g. after growing bacteria)
Antigen Testing
For Neisseria species, it is also used for tracking infection and vaccine design
Give examples of bacteria used in Antigen Testing?
E.coli 0157 (via the O and H antigens) Legionella Strep. Pyogenes Strep. Pneumoniae Shigella species Salmonella species (via the O antigens) Neisseria species
If bacteria is present on a swab, does it always indicate infection?
NO.
Bacteria could be a Normal Commensal Bacteria. Only consider infection IF there is inflammation and other signs of infection present, even if the bacteria is commensal.
Which infection is transmitted via sneezing?
Measles
