BACTERIAL PATHOGENS Flashcards
STAPHYLOCOCCUS AURIES
- Nasal carriage in 50% people
- can cause bacteraemia, septicaemia, pneumonia and meningits.
- produces exoenzymes and toxins
STAPHYLOCOCCUS EPIDERMIS
- opportunistic skin commensal pathogen
- causes infection in association with ‘foreign bodies’ eg intravascular catheters. adheres to plastics/metals using glycocalyx (slime).
- slower acting than auries. high temp and pain.
STREPTOCOCCUS PYOGENES
- group A strep.
- commonest cause of bacterial sore throat.
- causes scarlet fever (strawberry tongue), pneumonia
- gram positive
STREPTOCOCCUS PNEUMONIAE
- commonest cause of bacterial pneumonia
- commonest cause of bacterial meningitis (except in neonates)
STREPTOCOCCUS AGALACTIA
- group B strep
- commonest cause of bacterial meningitis and sepsis in neonates
STREPTOCOCCUS MILLERI COMPLEX
- 3 closely related species of pus forming cocci.
- associated with abscesses e.g dental
VIRIDENS STREPTOCOCCI
- a- haemolytic streptococci inhabit upper resp. tract.
- cause sub-acute bacterial endocarditis
STREPTOCOCCUS GALLOLYTICUS
- (former name S.BOVIS)
- a-haemolytic strep that forms part of normal bowel flora.
- bacteraemia of this –> colonic malignancies
LISTERA MONOCYTOGENES
- gram +ve , Zoonosis
- rare cause of sepsis and meningitis in pregnancy, neonates and the immunosupressed.
- associated with unpasteurised milk
CORYNEBACTERIUM species
- gram +ve
- opportunistic infections with trauma and devices
- eg corynebacterium diptheria
PROPIONIBACTERIUM acnes
- gram +ve
- associated with acne
- device associated and post-procedural infecitons
ENTEROBACTERIACEAE
- gram -ve found in bowel flora
- e.g E.COLI which is commonest cause of UTI and bacteraemia.
- source of nosocomial (health-care) infections
- colonise shorter urethra in females and can develop antibiotic resistance.
PSUDOMONAS AERUGINOSA
- gram -ve multi resistant.
- opportunistic: causes resp infections, UTI
- GREEN PIGMENT
NEISSERIA MENINGITIS
- gram -ve
- causes meningococcal sepsis/ meningitis
- classic purpuric non-blanching rash
NEISSERIA GONORRHOEAE
- gram -ve : cause of gonorrhora
- rare to cause invasive infections 2ndary to primary STI.
-HAEMOPHILLUS influenzae
- gram -ve
- forms normal resp.tract flora and infections eg pneuonia
- type b (capsulated) causes meningitis and epiglottitis. only type b prevented by Hib vaccine.
HACEK organisms
- unusual cause of infective endocarditis
- Haemophilus parainfluenzae,
- Haemophilus aphrophilus,
- Actinobacillus actinomycetemcomitans,
- Cardiobacterium hominis,
- Eikenella corrodens, and Kingella kingae.
SPIROCHETES
- Treponemaa pallidium –> syphilis
- other species cause leptospirosis and lyme disease
Cell-wall free
- MYCOPLASMA PNEUMONIAE
- LEGIONELLA PNEUMONIAE
- C. TRACHOMATIS (chalmydia species and commonest STI)
ANAEROBES
- Bcteriodes fragilis
- e.g clostridium species: C.dofficile, C.tetani, C.botulinum
MYCOBACTERIA
- AFB acid fast bacilli
dont stain conventionally ie gram
Mycobacterium tuberculosis –> tb
others are opportunistic in AIDS patients
