Flashcards in Uvea Deck (35)
What is iritis, and what are some other terms for it?
Iritis is the term commonly used for inflammation of the anterior uvea.
However, because the anterior ciliary body is usually involved, the anatomically more correct designation is anterior uveitis or iridocyclitis.
It may be acute or chronic, and can affect one or both eyes. It is often idiopathic, likely to include both genetic and environmental factors. Recurrent episodes of idiopathic acute iritis are common.
What are the five symptoms of iritis (anterior uveitis, or iridocyclitis?)
1. Pain (an ache, aggravated by reading)
3. Photophobia (from reactive spasm of inflamed iris muscle)
4. Watering (lacrimation)
5. Blurred vision (secondary to inflammatory cells and flare in the anterior chamber; accommodation may be impaired).
What are the six signs of iritis?
1. Redness (in early stages, may be confined to limbal area - ciliary flush, circumcorneal injection - eyelid conjunctiva spared)
2. Inflammatory cells and flare (proteinaceous exudate in anterior chamber - appearance similar to beam of a projector passing through smoke in a darkened room - or hypopyon as cells settle in inferior anterior chamber angle).
3. Keratic precipitates (KPs, clumps of inflammatory cells on corneal endothelium, usually on the inferior half).
4. Miosis (spasm of the sphincter muscle of the pupil).
5. IOP - can be low, high, or normal.
6. Fundus - examine thoroughly.
What are posterior synechiae?
In iritis, after spasm of the sphincter muscle of the pupil (causing miosis), focal inflammatory adhesions between the pupil margin and the lens (posterior synechiae) are caused by inflammatory mediators and are typical of iritis.
About half of patients with acute iridocyclitis are positive for what?
HLA B27, although its significance is not understood.
Specific investigations for the most common causes of iridocyclitis are performed when?
Only if the iritis is recurrent, persistent, bilateral, resistance to standard therapy, and granulomatous inflammation.
Initial patient assessment includes an attempt to detect a cause. This involves a simple systems inquiry, which may suggest appropriate investigations. Then turn to specific Ix as indicated above.
Name 4 ocular causes of iridocyclitis.
1. Herpes virus: infections of the eye and periocular structures - herpes zoster ophthalmicus, herpes simplex keratitis, etc. Acute glaucoma is an importsnt complication.
2. Fuchs' heterochromic cyclitis
3. Trauma (incl. surgery) - common cause of anterior segment inflammation
4. Sympathetic ophthalmitis (a rare bilateral granulomatous panuveitis occurring weeks to months after penetrating injury).
What is Fuchs' heterochromic cyclitis?
A low grade but chronic unilateral iridiocyclitis (iritis) characterised by heterochromia (difference in colour between the two irises, owing to diffuse iris atrophy), file stellate KPs (keratic precipitates) across the entire endothelium and the absence of posterior synechiae.
Cataract and glaucoma are long-term complications.
Pts usually present with floaters and cataract.
Try and name 10 systemic causes of iridocyclitis.
1. Seronegative arthritides (HLA B27 association)
2. Ankylosing spondylitis
3. Reiter's syndrome
4. Psoriatic arthritis
5. IBD (Crohn's, UC)
6. Juvenile chronic arthritis (cataract, glaucoma, macular oedema = common complications).
7. Sarcoidosis (granulomatous anterior uveitis)
8. Behçet's disease (a systemic vasculitis)
9. Tuberculosis (rare cause)
10. Syphilis (granulomatous and non-granulomatous)
11. Masquerade syndromes (a range of conditions in which uveal inflammation is not the primary pathology. eg. Retinal detachment, neoplasia, bacterial endophthalmitis, presence of occult intraocular foreign body.
Name 7 investigations which may be included when worried about iritis (as directed by clinical suspicion)?
3. serum ACE level
4. Syphilis serology
5. HLA typing
7. Sacroiliac joint Xray
Refer to physician if evidence of systemic disease.
What is the mainstay of iritis treatment?
Topical steroids (prednisolone, betamethasone, dexamethasone) which can be varied in concentration and frequency according to the severity of inflammation.
Usually drops for daytime, and ointment at night.
Subconjunctival steroids and mydriatics for severe cases.
Deep orbital injection of depot steroid preparations useful for posterior segment inflammation and for maculsr oedema.
Systemic steroids & immunosuppressants reserved for resistant, dight-threatening disease.
Besides steroids, what else can help to ease the discomfort in iritis and what is a prophylactic bonus of this?
A topical mydriatic, such as cyclopentolate.
This also prevents the formation of posterior synechiae.
What needs to be monitored regularly during active iritis?
May be elevated by iritis itself, or by topical steroid use.
Name three complications of iritis.
3. Macular oedema
Define posterior uveitis.
Inflammation of the choroid (as opposed to anterior: iris and ciliary body).
Name two main symptoms of posterior uveitis, and two rare symptoms.
1. Floaters (vitreous opacities consisting of debris and inflammatory cells)
2. Decreased vision
Rare: pain and redness.
Name three other causes of cells in the vitreous.
2. Retinal tears
3. HIV infection
Is posterior uveitis due to a local disorder or systemic disease?
As with anterior uveitis, it can be either local or due to a systemic disease.
Name some ophthalmoscopic features of posterior segment inflammation (uveitis):
1. Vitritis: inflammatory cells in the vitreous
2. Vasculitis (?candlewax exudate, venous sheathing, RV occlusion)
3. Cotton wool spots
4. Macular oedema (cystoid)
5. Optic disc swelling
6. Foci of chorioretinal inflammation or scarring
There may be mild anterior uveitis, seen on slit lamp examination only.
After general and ocular Hx to indicate a disease process, name 7 other investigations of posterior segment inflammation.
3. ACE levels (elevated in sarcoidosis)
4. Syphilis serology
5. Toxoplasma serology
6. CXR (sarcoidosis and tuberculosis)
7. Fundus fluorescein angiogram: can show disease-specific lesions (occult vasculitis, macular oedema or ischaemia); baseline for future reference; identify cause of loss of vision.
What is the most common cause of posterior segment inflammation in the developed world?
Toxoplasmosis (toxoplasma gondii, a protozoan).
About 50% of population positive for Abs, but not indicative of active inflammation so a positive result is unhelpful. A negative result in an immunocompetent pt makes a diagnosis of toxoplasma retinochoroiditis unlikely.
How would toxoplasma retinochoroiditis appear on ophthalmoscopy?
One or more foci of activity will usually be visible (in active disease) as a whitish patch with moderately well define borders and overlying vitreous inflammation, sometimes located at the edge of an old pigmented (blackish) scar.
Reactivation of an old ocular lesion tends to occur early in adulthood, causing floaters and blurred vision.
Treatment of toxoplasma retinochoroiditis?
Most cases of reactivation resolve spontaneously without impairment of vision, so do not require Rx.
Systemic Rx indicated where vision is significantly affected or threatened, such as when a lesion is close to the macula or optic nerve.
Oral steroids suppress inflammation, but concurrent antimicrobial Rx important. ABx, often in combination, include clindamycin (beware pseudomembranous colitis), sulphonamides, and pyrimethamine (with folic acid).
How would sarcoidosis posterior uveitis present?
Unusual for the fundus to be involved without some degree of anterior uveitis, therefore it tends to present with pain and redness in addition to floaters and loss of vision.
Name three features on ophthalmoscopy which are characteristic of sarcoidosis posterior uveitis.
1. Snowballs (vitreous inflammatory cells and opacities)
2. Venous sheathing
3. Candlewax drippings (perivenous exudates)
Retinal and choroidal nodules may be seen. The optic disc can be swollen as a result of of infiltration.
Treatment of sarcoidosis posterior uveitis?
Systemic Rx via physician.
Mild ocular inflammation may be treated with a topical steroid and a mydriatic. Periocular depot steroid injections, systemic steroids and systemic cyclosporin A are reserved for severe or resistant cases in which permanent visual loss is likely.
Name three systemic vasculidites in which the eye may experience vasculitis (posterior uveitis).
2. Polyarteritis nodosa
3. Wegener's granulomatosis
What can be a cause of posterior uveitis, iridocyclitis, vitritis, and occlusive vasculitis, and how is it treated?
Syphilis can cause all of the above. Always check it out with non-specific signs. Treatment with penicillin or erythromycin.
What is the pattern of pigmentary retinopathy in congenital syphilis chorioretinitis?
Salt and pepper pattern.