Microbiology Flashcards
What is the medical term for inflammation:
of the whole eye
and
inflammation of the Cornea
Endophthalmitis
Keratitis
What are the top causes of conjunctivitis in neonates?
Staph aureus
Neisseria gonorrhoeae
Chlamydia trachomatis
what are the top causes of conjunctivitis in adults and children?
Staph aureus
Strep pneumonia
Haemophilus influenzae (especially in children)
what anti-biotic should be used for conjunctivitis?
Chloramphenical qds
what are the contraindications for chloramphenical?
aplastic anaemia
allergy
what are the common causes of conjunctivitis with contact lenses?
acanthamoeba
pseudonomas aeruginosa
list common viral causes of conjunctivitis
adenovirus
herpes simplex
herpes zoster
what’s the classic presentation of chlamydial conjunctivitis?
chronic,
resistant to treatment
bilateral presentation in young adults
What condition does this picture show?
What is the condition usuallly associated with?
How is it treated?
bacterial keratitis with hypopyon
Associated with pathology of cornea or contact lense wear
admission and cloramphenicol
What condition is shown in the picture?
How does it present?
What can happen when it is treated with steroids?
Herpetic keratitis : dendritic ulcer
Very painful
Corneal meslt and perforation
how does adenoviral keratitis present?
What are the treatments?
usually follows a urti
may affect sight
Bilateral
AB to prevent secondary infection
steroids to speed up recovery if it becomes chronic
What is the presentation of fungal keratitis
trauma from vegitation
slow onset
What is the presentation of Orbital Cellulitis?
Proptosis
Pain, especially on movement
Paranasal sinusitis
Fever
What investigations should you carry out for orbital cellulitis?
CT scan for orbital abscesses
which is more serious preseptal or orbital cellulitis?
Orbital
what are causal organsims for orbital cellulitis?
Staphylococci
Streptococci
Coliforms
Haemophilus influenzae
anaerobes
Treatment of orbital cellulits
scan if there is any suggestion of muscle or optic nerve dysfunction
Give Broad spectrum antibiotics
Abscess will require drainage
What condition is shown in the picture and how does it present?
Endophthalmitis
very red, very painful eye with decreasing vision
what are the most common causes of endopthalmitis?
Often conjunctival “commensals”
Most common is staph epidermidis
what is the treatment for endophthalmitis?
Intravitreal amikacin and vancomycin
And topical antibiotics
name the top 3 causes of chorioretinitis
CMV in AIDS
Toxoplasma gondii- Self limiting, mild-flu like symptoms
Toxocara canis (worm)- self-limiting (parasite can’t reproduce in humans) but can cause permanent damage through granuloma formation.
What techniques are used to diagnose an eye infection?
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
treatment of bacterial conjunctivitis
chloramphenicol
(treats most bacteria except Pseudomonas aeruginosa)
fusidic acid
(treats Staph. aureus)
gentamicin
(treats most Gram negative bacteria including coliforms, Pseudomonas aeruginosa)
treatment of chlamydial conjunctivitis
topical oxytetracycline
(but adults may also need oral azithromycin treament for genital chlamydia infection)
treatment of bacterial keratitis
4-quinolone (Ofloxacin)
(treats most Gram negative bacteria including coliforms, Pseudomonas aeruginosa, Haemophilus influenzae. Not active vs. Strep. pneumoniae)
Gentamicin and cefuroxime
(the combination will treat most Gram positive and Gram negative organisms)
What is this condition called and what causes it?
Dacrocystitis
is an infection of the lacrimal sac, secondary to obstruction of the nasolacrimal duct
