Microbiology Flashcards
What are the 4 steps of organism invasion?
- Introduction
- Establishment
- Growth and spread
- Impact
What are the 6 steps of pathogenic infection?
Exposure Adhesion Invasion Colonization Toxicity Tissue damage + disease
What is a pathogen?
Any microorganism that has the potential to cause disease
Define sepsis?
A life-threatening organ dysfunction caused by a dysregulated host response to infection
What immune system component responds to bacteria?
Phagocytes
Antibody and B lymphocytes
Complement
What immune system component responds to viruses?
T lymphocytes
Antibody and B lymphocytes
What immune system component responds to fungi?
Phagocytes
T lymphocytes
Eosinophils
What immune system component responds to protozoa?
T lymphocytes
Eosinophils
What immune system component responds to worms?
Eosinophils
Mast cells
Describe the period of communicability
Invasion Incubation (sub-clinical infection) Prodromal period (early symptoms) Ilness period Convalescent period
What is alpha haemolysis?
Partial haemolysis
What is beta haemolysis?
Complete haemolysis
What is gamma haemolysis?
No haemolysis
What are some examples of aerobic organisms?
Staphylococci
Streptococci
Enterococci
Coliforms
What is the classification of E.coli?
Name some other bacteria in this group
Gram -ve bacilli
Lactose +
Fast fermenter
Enterobacter
Klebsiella
What pathogens are commonly found in the mouth?
Strep viridans
Neisseria
Anaerobes
Candida
Staphylococci
What pathogens are found in the stomach/duodenum?
Usually sterile
Normal flora of the jejunum
Coliforms and anaerobes
Normal flora of the colon
Coliforms
Anaerobes
Enterococcus faecalis
What are coliforms
Gram -ve rods e.g. E.coli
What is the drug of choice for sepsis and coliforms?
Gentamicin
Aztreonam if gentamicin contraindications
Co-trimoxazole for oral switch
What is the drug of choice for sepsis and anaerobes?
Metronidazole
What is the drug of choice for sepsis and gram +ve cocci?
Amoxicillin
Co-trimoxazole if amox contraindications
Co-trimox for oral switch
Name a gram +ve cocci
Enterococci
What antibiotic can be used to kill enterococci?
Vancomycin
What is the treatment for a severe C.diff infection?
Vancomycin +/- metronidazole
What is the treatment for peritonitis/biliary tract/intra-abdominal infection?
IV amox, met + gent
What is the treatment for proven spontaneous bacterial periotonitis?
Severe - pip/taz
Mild - co-trimox
What is the classification of haemophilus influenzae?
Gram -ve coccobacillus
What does haemophilus influenzae grow on?
Chocolate agar media
Name some atypical pneumonia
Mycoplasma pneumoniae
Coxiella burnetii
Chlamydophila psittaci
Legionella
What do most atypical pneumonias respond to?
Doxycycline
What pneumonia can people get from sheep and goats?
Coxiella burnetii
Psittacosis and avian chlamydiosis are common in what pet owners?
Bird owners
How can atypicals be diagnosed?
Serology
PCR
How are viruses tested?
PCR
What test would you do if you suspected legionella?
Urine legionella antigen
What agar does legionella grow on?
BCYE
What top bottle should you use for urine culture in the community?
Red top
What top vacutainer do you use for serology of atypicals?
Gold top
Name an aminoglycoside
Gentamicin
What class of drugs does gentamicin belong to?
Aminoglycosides
Name a quinolone
Levofloxacin
What class of drugs does ciprofloxacin belong to?
Quinolones
What should be monitored when prescribing gentamicin?
Renal function
What signs/symptoms might a patient who has sepsis have?
V high or low temp Uncontrolled shivering Confusion Cold/blotchy hands/feet Not passing as much urine as normal