Eye, red and tender

Question 1

Probability diagnosis

Answer 1

Conjunctivitis:

1. bacterial
2. adenovirus
3. allergic

Acute conjunctivitis accounts for over 25% of all eye complaints seen in general practice.

Question 2

Serious disorders not to be missed

Answer 2

1. Acute glaucoma
2. Uveitis:

• acute iritis
• choroiditis

1. Corneal ulcer
2. Corneal injury: abrasion/foreign body
3. Herpes simplex keratitis
4. Microbial keratitis (e.g. fungal, amoeba, bacterial)
5. Herpes zoster ophthalmicus
6. Penetrating injury
7. Endophthalmitis
8. Orbital cellulitis
9. Trachoma

Question 3

Pitfalls (often missed)

Answer 3

Scleritis/episcleritis

Foreign body (esp. IOFB)

Trauma—contusion, penetrating injury

Ultraviolet light ‘keratitis’

Blepharitis

Rarities:

• cavernous sinus arteriovenous fistula
• primary tumour of eye

Question 4

Masquerades checklist

Answer 4

Drugs (hypersensitivity)

Thyroid disorder (hyperthyroidism)

Question 5

Key history

Answer 5

The five essentials of the history are:

• hx of trauma, especially as indicator of intraocular foreign body (IOFB)
• vision
• the degree and type of discomfort
• presence of discharge
• presence of photophobia.

Consider association with spondyloarthropathies.

Question 6

Key examination

Answer 6

When examining the unilateral red eye keep the following diagnoses in mind:

• trauma
• foreign body, including IOFB
• corneal ulcer
• iritis (uveitis)
• viral conjunctivitis (commonest type)
• acute glaucoma

The four essentials of the examination are:

• testing and recording vision
• meticulous inspection under magnification (slit lamp is ideal)
• testing the pupils
• testing ocular tension

Question 7

Key investigations

Answer 7

May include swab of discharge for MC, visual acuity

ESR/CRP

HLAB27

Consider specialist referral

Question 8

Diagnostic tips

Answer 8

Pain and visual loss suggest a serious condition such as:

• glaucoma
• uveitis (inc. acute iritis) or
• corneal ulceration

A purulent discharge indicates bacterial conjunctivitis.

A clear or mucus discharge indicates viral or allergic conjunctivitis.

Question 9

The clinical approach

Answer 9

The five essentials of the history are:

1. history of trauma (esp. as indicator of IOFB)
2. vision
3. the degree and type of discomfort
4. presence of discharge
5. presence of photophobia

Question 10

When examining the unilateral red eye, keep the following diagnoses in mind:

Answer 10

Beware of the unilateral red eye:

—think beyond bacterial or allergic conjunctivitis.

It is rarely conjunctivitis and may be a:

1. viral conjunctivitis (commonest type)
2. corneal ulcer
3. keratitis
4. foreign body, inc. IOFB
5. trauma
6. iritis (uveitis)
7. acute glaucoma

Question 11

Red flags and ‘golden rules’ for red eye

Answer 11

Always test and record vision

Beware of the unilateral red eye

Conjunctivits is almost always bilateral

Irritated eyes are often dry

Never use steroids if herpes simplex is suspected

A penetrating eye injury is an emergency

Consider an intra-ocular foreign body

Beware of herpes zoster ophthalmicus if the nose is involved

Irregular pupils: think iritis, injury and surgery

Never pad a discharging eye

Refer patients with eyelid ulcers

If there is a corneal abrasion, look for a foreign body

Source: Based on J Colvin and J Reich

Question 12

Red eye in children

Answer 12

Of particular concern is orbital cellulitis,

• which may present as a unilateral swollen lid
• and can rapidly lead to blindness if untreated.

Bacterial, viral and allergic conjunctivitis are common in all children.

Conjunctivitis in infants is a serious disorder because of the immaturity of tissues and defence mechanisms.