Microbiology Flashcards
List the main organisms that cause neonatal bacterial conjunctivitis
Staph. aureus
Neisseria gonorrhoea
Chlamydia trachomatis
All cases of neonatal bacterial conjunctivitis should be referred. True/False?
True
List the main organisms that cause bacterial conjunctivitis
Staph. aureus
Strep. pneumoniae
H. influenzae
List symptoms of bacterial conjunctivitis
Red, hot eyes
Hazy vision
Sticky discharge
Eyelids stick together
Bacterial swabs should be taken prior to prescribing antibiotics for bacterial conjunctivitis. True/False?
True
What is the main topical antibiotic for bacterial conjunctivitis?
Chloramphenicol
When must chloramphenicol be avoided?
History of aplastic anaemia
Allergy
How does discharge in bacterial conjunctivitis differ from adenoviral conjunctivitis?
Bacterial: sticky
Adenoviral: watery, gritty
List the 3 main organisms that cause viral conjunctivitis
Herpes simplex
Adenovirus
Herpes zoster (HZ ophthalmicus - shingles in eye)
When should chlamydial conjunctivitis be suspected?
Unresponsive to treatment/chronic
Bilateral conjunctivitis in young adults
Less discharge + less irritating
Lymphocyte follicles
What is hypopyon? What eye pathology is it typically found in?
Inflammatory cells in the anterior chamber of the eye
Appears as exudate over the eye
Bacterial or fungal keratitis
What type of ulcer can result from viral herpetic keratitis? What are the other symptoms?
Dendritic ulcer (branching)
Very painful eye
Reduced corneal sensation
Bacterial keratitis usually occurs in association with _____
Corneal disease
Contact lens wear
Herpetic keratitis should be treated with steroids. True/False?
FALSE
Steroids can cause corneal melt + perforation
List symptoms of orbital cellulitis
Painful eye movements Proptosis Pyrexia Swelling Sight-threatening
List the main organisms that cause orbital cellulitis
Staph. Strep. Coliforms H. influenzae Anaerobes
IV antibiotics may be started before culture results in orbital cellulitis. True/False?
True
Broad-spectrum antibiotics and abscess drainage
What is endophthalmitis and how is it usually caused?
Devastating infection of whole globe inside the eye
Trauma, nail guns, surgery, injections
What is the most common organism cause of endophthalmitis?
Conjunctival commensals - Staph. epidermidis
Outline treatment of endophthalmitis
Intravitreal amikacin + vancomycin
Topical antibiotics
List the main causes of chorioretinitis
CMV in AIDS
Toxoplasma gondii
Toxocara canis
What type of infection is toxoplasmosis?
Protozoan
What is toxocara?
Roundworm infection that affects cats/dogs but can spread to humans
What is the danger of toxocara?
Can form granules to cause irreversible visual loss
What are the 3 main types of eye swabs?
Bacterial
Viral
Chlamydial
What investigation may be done for bacterial keratitis?
Corneal scrape
What investigation may be done for endophthalmitis?
Vitreous/aqueous culture
When might antivirals be used for eye disease?
Dendritic ulcers of the cornea
What is the main treatment for chlamydial conjunctivitis?
Topical oxytetracycline
Azithromycin for adult general infection
List medications used to treat bacterial keratitis
Ofloxacin
Gentamicin
Cefroxime
What is characteristic about fungal keratitis?
Lazy lesion with long healing time
List the possible sources of infection in orbital cellulitis
Extension direct from sinus
Facial orbital infection (infected chalazion - eyelid lump, blocked oil gland ‘meibomion)
Dacrocystitis (infected lacrimal sac, obstructed nasolacrimal duct)
Post-op
Which investigation should be performed if orbital cellulitis is suspected?
CT scan
List the symptoms and signs of endophthalmitis
Pain
Reduced vision
Red eye
Sight threatening
