An Introduction to Medical Microbiology Flashcards
What are possible infecting agents?
Bacteria
Viruses
Fungi
Parasites
Prions
What are the two areas of the body in terms of organisms?
Sterile and non-sterile
What is a sterile site?
One which normally does not have infection
What is a non-sterile sites?
One which has some degree of harmless infection, usually associated with the outside world
What are examples of sterile sites?
Blood
Cerebrospinal fluid (CSF)
Lung
Bladder
What are examples of non-sterile sites?
Skin
Nasopharynx
Urethra
Gut
Which kind of sites is easier to diagnose a harmful infection?
Sterile sites because you are not expecting to find anything there
What are some common speciments collected for bacterial culture?
Mid-stream urine (urinary tract infection)
Sputum (chest infection)
Throat swab (tonsillitis)
Swab or pus (wound or site of infection)
Faeces (diarrhoea)
Blood culture (bacteraemia)
Cerebro-spinal fluid (meningitis)
What are different ways of looking for pathogens?
Microscopy
Gram stain and microscopy
Bacterial culture
In what site does microscopy work well?
Sterile sites but not non-sterile sites
What can microscopes not see?
Viruses, they are too small
What can unstained microscopy see?
Pus cells (in urine)
Parasites (in faeces)
What is stained microscopy used to see?
Yeasts
Fungi
How can flourescent bacteria be seen?
By using flourescent staining such as auramine. such as for mycobacteria
What does gram staining identify?
Whether the bacteria is gram negative or gram positive
How does gram negative bacteria appear when gram staining?
Pale red