Uveitis and Conjunctivitis

Question 1

What is conjunctivitis?

Answer 1

Inflammation of the lining of the eyelids and eyeball.

Question 2

What is the aetiology of conjunctivitis? (x6 (x6 and x6))

Answer 2

• Bacterial (Pneumococcus, Staph. aureus, Moraxella catarrhalis, H. influenzae, N. gonorrhoeae, Chlamydia) with transmission from genitalia to the hands and then eyes; highly contagious
• Viral (adenovirus, HSV, EBV, molluscum contagiosum, coxsackie, and enteroviruses); highly contagious
• Allergic: atopic/seasonal conjunctivitis
• Immunological
• Mechanical irritation such as contact lenses, floppy eyelid syndrome
• Drugs: glaucoma medications, some antibiotics and antivirals contain benzalkonium chloride which accumulate in the conjunctiva in chronic administration

Question 3

What is the pathophysiology of (i) infective and (ii) allergic conjunctivitis?

Answer 3

• Conjunctiva contains non-keratinising squamous epithelium and a thin, richly vascularised, transparent stroma called substantia propria. Also contains accessory lacrimal glands and goblet cells.
• (i) Pathogens replicate within conjunctival mucosal cells causing inflammatory cascade
• (ii) Type I immune response to allergen with mast cell and cross-linking to IgE. Result is mast cell degranulation of histamine, itching, increased vascular permeability and inflammatory cascade.

Question 4

What are the signs and symptoms of conjunctivitis? (x4)

Answer 4

• Irritated red eye with pain/itching
• Watery/mucoid/purulent discharge
• Eyelids stuck together in morning (bacterial and viral)
• Tender, pre-auricular lymphadenopathy

Question 5

What are the characteristics of allergic conjunctivitis? (x3)

Answer 5

Bilateral and mucoid discharge. Itching more common

Question 6

What are the characteristics of Neisseria gonorrhoeae conjunctivitis?

Answer 6

Hyperacute purulent conjunctivitis.

Question 7

What are the characteristics of Chlamydia conjunctivitis?

Answer 7

Persistent conjunctivitis.

Question 8

What are the characteristics of viral conjunctivitides? (x4)

Answer 8

Keratoconjunctivitis (inflammation of conjunctiva AND CORNEA (keratitis)), follicular conjunctivitis (follicles in eyelid conjunctiva – see photo), and superficial punctate keratopathy (death of corneal cells; eyes become red, watery and sensitive to light). Watery discharge more common in viral.

Question 9

What are the investigations for conjunctivitis? (x2)

Answer 9

• Clinical diagnosis.
• ADENOVRIUS IMMUNOASSAY: diagnose adenovirus aetiology
• CELL CULTURE/PCR: bacteria and viral aetiology

Question 10

What is the uvea?

Answer 10

Middle layer of eye, comprising of iris, ciliary body and choroid.

Question 11

What is uveitis? Three types?

Answer 11

Inflammation of the anterior uvea (well vascularised; iris and ciliary body). Can also have intermediate uveitis (posterior ciliary body and pars plana (sandwiched portion of ciliary body)) and posterior uveitis (posterior vitreous, retina, choroid and optic nerve).

Question 12

What is iritis?

Answer 12

Inflammation of iris

Question 13

What is iridocyclitis?

Answer 13

Iris and ciliary body

Question 14

What is the aetiology of uveitis? (x4)

Answer 14

• Most commonly idiopathic
• Infection e.g., HSC, herpes zoster
• Manifestation of systemic inflammatory conditions such as arthritis, HLA B27-related spondyloarthritides (ankylosing spondylitis, reactive arthritis), IBD, sarcoidosis, Behcet’s disease
• Sympathetic ophthalmia: inflammation of the contralateral eye weeks/months after penetrating injury
• Neoplasm

Question 15

What is the pathophysiology of uveitis?

Answer 15

In each aetiology, there is ocular inflammation. Depending on aetiology, this leads to damage caused by direct tissue damage, or – in autoimmune disorders – damage is caused by immune complex formation and deposition in the blood vessels, or cell-mediated responses.

Question 16

What is the epidemiology of uveitis: Age? Gender?

Answer 16

Peak age is 30-40. Spondylarthritis-associated uveitis is twice as common in men.

Question 17

What are the signs and symptoms of anterior uveitis? (x8) PPP VR HiS L

Answer 17

• Pain from ciliary spasm and inflammation which increases on accommodation
• Photophobia
• PUPILS: Small irregular pupil due to posterior synechiae (adhesion of iris to the lens) or anterior synechiae (adhesion of iris to the cornea)
• VISION: blurred vision, decreased visual acuity, flare is a hallmark
• Red eyes, may be confined to the corneoscleral junction (called ciliary flush)
• Hypopyon: proteinaceous exudate and inflammatory cells in the inferior angle of the anterior chamber
• SLIT LAMP: shows keratic precipitates (opaque spots; deposits of leucocytes on the corneal endothelium) and floaters (WBC floating in the fluid)
• Lacrimation

Question 18

How do you differentiate between conjunctivitis and uveitis? (x4)

Answer 18

• Uveitis sees inflammation that may extend to iris. In uveitis, the redness is most intense at the border of the iris; in conjunctivitis, the redness is most intense more peripherally
• Consensual photophobia occurs in uveitis (when iris affected) – pain in affected eye when light shone in unaffected eye
• Keratic precipitates and floaters in uveitis
• Uveitis is more associated with pain than conjunctivitis

Question 19

What are the investigations for anterior uveitis?

Answer 19

• Diagnosis is clinical
• Investigate for associated systemic conditions depending on associated symptoms
• Fundoscopy: exclude retinal detachment or posterior inflammation