Randoms Flashcards
(25 cards)
What does a Medical Microbiologist do?
Diagnoses infections, advises on tests and treatment, infection control, antibiotic policy.
What are sterile specimen sites?
Blood, CSF, lung, bladder.
What are non-sterile specimen sites?
Skin, nasopharynx, urethra, gut.
What is the purpose of a Gram stain?
To classify bacteria as Gram-positive or Gram-negative and guide antibiotic choice.
Why is bacterial culture used despite being slow?
It is sensitive and helps in organism identification and antibiotic testing.
What is phage typing?
Use of bacteriophages to identify bacterial strains based on lysis patterns.
What is the role of latex agglutination tests?
Serotyping based on antigen-antibody reaction.
What are the main signs of clinical infection?
Inflammation, fever, pain, tachycardia, high CRP, high white blood cell count.
What are Koch’s postulates?
Criteria to link a microbe to a disease: isolation, culture, reinfection.
What is infectivity?
The ability of a microorganism to become established in the host.
What is virulence?
The capacity to cause harmful effects, mediated by virulence factors.
Name three types of bacterial toxins.
Exotoxins, enterotoxins, endotoxins.
What is a superantigen?
An exotoxin causing massive, nonspecific T-cell activation and cytokine storm.
What causes toxic shock syndrome?
Superantigens from Staphylococcus aureus or Streptococcus pyogenes.
What is MRSA?
Methicillin-resistant Staphylococcus aureus, resistant to β-lactam antibiotics.
What does coagulase-positive mean?
The organism (e.g., S. aureus) produces coagulase, distinguishing it from other staphylococci.
What is the main pathogen among α-haemolytic streptococci?
Streptococcus pneumoniae.
Which Gram-negative cocci cause meningitis and urethritis?
Neisseria meningitidis and Neisseria gonorrhoeae.
What is the role of E. coli in disease?
Causes UTIs, diarrhoea, produces exotoxins, has multiple serotypes.
How is Salmonella enterica identified?
Non-lactose fermenter, self-limiting diarrhoea, >1500 serotypes.
Which bacterium causes typhoid fever?
Salmonella typhi.
What is the commonest cause of bacterial diarrhoea in the UK?
Campylobacter spp.
What is unique about Mycobacterium species?
Require Ziehl-Neelsen staining; acid-fast; cause TB and leprosy.
How is syphilis caused and detected?
By Treponema pallidum; diagnosed via serology.
