Microbiology Flashcards
What type of bacteria is H influenza?
gram negative cocci-bacilli
What type of bacteria is pseudomonas?
gram negative bacilli
What type of bacteria is niesseria?
gram negative cocci
What is inflammation of the entire globe of the eye?
endophthalmitis
What is inflammation of the cornea?
keratitis
What bacteria cause bacterial conjunctivitis in neonates?
Staph aureus
Neisseria gonorrhoeae
Chlamydia trachomatis
What bacteria cause bacterial conjunctivitis in other ages?
Staph aureus
Strep pneumoniae
Haemophilus influenzae (especially in children)
What is a common contaminant of bottles?
Pseudomonas
What is the treatment of bacterial conjunctivitis?
Swab
Topical antibiotic usually chloramphenical qds
Drops vs ointment
Avoid chloramphenicol if history of aplastic anaemia or allergy
(Be aware of chloramphenicol allergy if worsening symptoms)
Which organisms cause contact lens infections?
Acanthamoeba
Pseudomonas aeruginosa
Which viruses may cause conjunctivitis?
Adenovirus
Herpes simplex
Herpes zoster
What should you suspect in bilateral conjunctivitis in young adults?
Chlamydial conjunctivitis
What is the treatment of bacterial keratitis?
Need admission for hourly drops
Daily review
What is bacterial keratitis often linked to?
Usually in association with other corneal pathology or contact lens wear
Descibe herpetic keratitis.
Very painful, can be recurrent - recurrences eventually result in reduced corneal sensation
What happens if herpetic keratitis is treated with steroids?
If treated with steroids can cause a corneal melt and perforation of the cornea
What does Adenoviral keratitis usually follow?
a UTI
Is orbital cellulitis painful?
Yes, especially on eye movements
What is orbital cellulitis often associated with?
paranasal sinusitis
Whiich organisms tend to cause orbital cellulitis?
Staphylococci Streptococci Coliforms Haemophilus influenzae anaerobes
How should you treat orbital cellulitis?
Broad spectrum AB and monitor closely
Sometimes an abscess will require drainage
What are symptoms of Endophthalmitis?
Painful +++, with decreasing vision
Very red eye
What is the most common bacterial cause of Endophthalmitis?
staph epidermidis
How should you treat Endophthalmitis?
Intravitreal amikacin and vancomycin and topical antibiotics
What can cause Chorioretinitis?
CMV in AIDS
Toxoplasma gondii
Toxocara canis (worm)
What is Toxoplasmosis?
Protozoan infection toxoplasmosis gondii
Mild flu like illness
Rarely causes any further problems
What is Toxocara canis (worm)?
Parasitic nemotode (roundworm)
Affects cats or dogs
Remains an immature form of the worm (larvae)
Form granulomas which can cause irreversible visual loss
How should eye infections be diagnosed?
Swabs for culture – bacterial, chlamydial, viral
Corneal scrapes in bacterial keratitis
Aqueous/vitreous for culture in endophthalmitis
Microscopy/culture for acanthamoeba
Serology for toxoplasma and toxocara
What bacteria does chloramphenicol not treat?
pseudomonas aeruginosa
What does fusidic acid treat?
staph aureus
How should you treat Chlamydial conjunctivitis?
topical oxytetracycline
but adults may also need oral azithromycin treament for genital chlamydia infection
How should you treat Herpetic conjunctivitis?
antivirals eg aciclovir
How should you treat bacterial conjunctivitis?
A 4-quinolone (Ofloxacin)
OR
Gentamicin and cefuroxime
