Microbiology Flashcards
what type and shape of bacteria is neisseria?
gram negative cocci
what type of shape of bacteria is h. influenzae?
gram -ve cocci-bacilli
gram -ve bacilli?
pseudomonas
what is an infection of the cornea called?
keratitis
what is an infection of the entire eyeball called?
endophthalmitis
watery red eye - bacterial or viral?
viral
gunky red eye - bacterial or viral?
bacterial
bacterial causes of bacterial conjunctivitis in neonates?
staph aureus
neisseria gonnorrhoeae
chlamydia trachomatis
bacterial causes of bacterial conjunctivitis in adults?
staph aureus
strep pneumoniae
haemophilus influenzae
first line investigation for bacterial conjunctivitis
bacterial swab
first line treatment and frequency for bacterial conjunctivitis
chloramphenical topical qds
contraindications of chloramphenicol
aplastic anaemia
allergy
viral causes of viral conjunctivitis
adenovirus
herpes simplex
herpes zoster
what should be done before a swab is taken of the eye?
anaesthetic
first line investigation for viral conjunctivitis?
viral PCR
what is hutcheson’s sign?
sign the nasociliary nerve is involved in CNV1 herpes zoster infection
appearance of chlamydial conjunctivitis?
“rice grain” appearance of the inner lid
slightly red eye
will chlamydial conjunctivitis present acutely or chronically?
chronic
consequence of chlamydial conjunctivitis?
subtarsal scarring
main component of the sclera?
collagen
white globs on eye with a hypopyon?
bacterial keratitis
what is a hypopyon?
collection of white cells at the bottom of the iris, looks like a white meniscus
gold standard treatment of bacterial keratitis?
hourly drops in hospital
cause of bacterial keratitis?
contact lens use
other corneal pathology
dendritic ulcers over eye?
herpetic keratitis
is herpetic keratitis painful or painless?
painful
what medication should be avoided in suspected herpetic keratitis and why
steroids
can cause a corneal melt or perforated cornea
best way to investigate a dendritic ulcer?
fluroscein stain and blue light
white subepithelial infiltrates on both eyes?
adenoviral keratitis
treatment for adenoviral keratitis?
topical antibiotic
steroids if becomes chronic
adenoviral keratitis is contagious T or F
T
most common cause of adenoviral keratitis?
URTI
fungal causes of keratitis from contact lenses?
acanthamoeba
pseydomonas aerugenosa
fungal keratitis heals relatively quickly T or F
F
slightly red eye that has been there for a while, not that sore?
fungal keratitis
what microbial eye problem can cause proptosis?
orbital cellulitis
associated symptoms with orbital cellulitis?
paranasal sinusitis
fever
first line investigation for orbital cellulitis?
CT scan to identify orbital abscesses
why is orbital cellulitis particularly worrying?
infection can go into the paranasal sinus and go to the brain
cause of orbital cellulitis?
focal orbital infection
op
will an infected sinus look grey or black on mri
grey
causative organisms of orbital cellulitis?
Staphylococci Streptococci Coliforms Haemophilus influenzae anaerobes
Tx for orbital cellulitis?
broad spec ab and monitor
if abscess, drain
cause of endophthalmitis?
post surgical
endogenous
endophthalamitis isnt painful T or F
F
how red is the eye in endophthalamitis?
very red
most common cause of endophthalmitis?
staph epi
other commensals of eye
Tx for endophthamitis?
intravitreal amikacin/ceftaazidime/vancomycin
+ topical abs
causative organisms of chorioretinitis?
CMV in aids (rare)
toxoplasma gondii
toxocara canis
“pizza fundus” on fundoscopy
CMV retinitis in AIDS
causes of toxoplasmosis?
cats
raw meat
symptoms of toxoplasmosis?
mild flu like symptoms
toxoplasma appearance on fundoscopy?
pigemented scar in the retina
problem with eye drops?
need to be stored in fridge
only last 28 days
toxocara sources?
cats
dogs
what microbial causes granulomas that cause visual loss?
toxocara
investigation for bacterial keratitis?
corneal scrape
Ix for endophthalamitis?
aqueous/vitreous for culture
Ix for acanthamoeba?
microscopy
culture
Ix for toxocara/toxoplasma infection?
serology
most commonly used topical antibiotic in opthalmology?
chloramphenicol
what kind of bacteria does chloramphenicol kill?
strep
haemophilus
what antibiotics inhibit cell wall synthesis?
cehalosporins
penicillins
what antibiotics inhibit nucleic acid synthesis?
quinolones eg ciprofloxacin
common contaminant of eyedrop bottles?
pseudomonas
what organism can chloramphenicol not treat?
pseuodomonas aeruginosa
what can fusidic acid treat?
staph aureus
what antibiotic is used for pseudomonas aeruginosa?
gentamicin
Tx for chlamydial conjunctivitis?
topical oxytetracycline
chlamydia treatment