AED - Conjunctival Infections I - Week 7 Flashcards
Define conjunctivitis.
Non specific term that means inflammation of the conjuctiva.
List 7 diverse aetiologies for conjunctivitis.
Viral
Bacterial
Allergic
Toxic
Contact lens related
Trauma
Lid/corneal pathology
List 5 possible symptoms of conjunctivitis.
Discomfort
-gritty, itchy, burning, scratchy
Discharge
-watery/mucoid/purulent/mucopurulent
Increased redness
Variable vision from discharge
Mild photophobia from PEE/SPK
List 4 possible signs of conjunctiva.
Little or no corneal involvement
Slight lid oedema
Lymphadenopathy
Pseudomembranes/membranes
List 5 features of conjunctivitis that can be used for a differential diagnosis.
Types of discharge
Types of conjunctival reaction (papillary vs follicular)
Pattern of hyperaemia
Presence of membranes/pseudomembranes
Presence/absence of lymphadenopathy
What 5 things can conjunctival discharge contain?
Exuldates from dilated conjunctival blood vessels
Mucus from goblet cells
Debris from dead/dying cells
Tear production
White blood cells (usually neutrophils)
Microorganisms
For the following types of conjunctival discharge, what is a rule of thumb on their possible cause:
Watery (2)
Mucoid (1)
Purulent (1)
Mucopurulent (3)
Watery - viral/allergic
Mucoid - allergic
Purulent - acute bacterial
Mucopurulent - mild/chronic bacterial or chlamydial
Is it normal to have follicles in the palpebral conjunctiva? What about in children?
Normal to have a few, especially in kids, but not apparent until >2 years old
Which region of the eye are follicles most common?
Forniceal conjunctiva
Follicles near what two structures of the eye indicate pathology?
Near the lid margin or the centre of the tarsus
What do follicles generally have at their base that distinguishes them from papillae?
Blood vessels, often surrounding them
How big are follicles generally? What does it depend on?
0.2 to 2mm
Depends on the severity and duration of inflammation
List three main acute causes of a follicular reaction.
Viral infections
Chlamydial infections
Medication hypersensitivity
What occurs for a follicle to appear?
Hyperplasia of lymphoid tissue in the conjunctival stroma
Are papillae more or less diagnostic than follicles?
Less diagnostic
Are papillae more or less variable in appearance compared to follicles?
More variable
What kind of core do papillae have?
Subepithelial fibrovascular core
Where on the eye can papillae generally be found (2)?
Palpebral conjunctiva and bulbar conjunctiva at the limbus
What is characteristic of papillae in appearance?
Central blood vessel
List 4 common causes of papillae.
Chronic blepharitis
Allergic disease
Bacterial infection
Contact lens related problems
What occurs for papillae to form (2)?
The tarsal conjunctiva undergoes a form of hyperplasia of its epithelium and infliltration of inflammatory cells
If there are follicles present and you see herpetic signs (dedrites, skin vesicles), what is a possible cause?
HSV
If there are follicles present and you dont see herpetic signs (dedrites, skin vesicles), what is a possible cause (2)?
Adenovirus
Chlamydia
What are three possible causes of non-follicular conjunctivitis?
Toxic conjunctivitis
Molluscum
Pediculosis
If there are papillae present with severe purulent discharge, what is a possible cause?
GC (gonococcal)
If there are papillae present with scant purulent discharge, what is a possible cause?
Bacterial other than GC
If there are papillae present with watery or mucoid discharge, what is a possible cause (2)?
Allergic
Atopic
What is a pseudomembrane? Is it adhered or loose? Can it be peeled off without bleeding? Does this leave the underlying conjunctival epithelium intact?
Coagulated fibrinous exudate lightly adhered to inflammed conjunctiva
Can be peeled without bleeding and leaves the conjunctival epithelium intact
List three main causes of pseudomembranes.
Adenoviral infections
Gonococcal conjunctivitis
Alkali burns