Uveitis
Uveitis - Summary
Uveitis (also known as iritis) is inflammation of the uveal tract (iris, ciliary body, and choroid). Inflammation of nearby tissues, such as the retina, the optic nerve, and the vitreous humour may also occur.
Uveitis is a potentially blinding condition that accounts for approximately 10% of people with visual impairment in the western world.
Uveitis can be classified based on which part of the eye is affected:
Anterior uveitis (the most common form) is inflammation in the anterior segment of the eye; this includes iritis (inflammation that is confined to the anterior chamber) and iridocyclitis (inflammation that is confined to the anterior chamber and anterior vitreous).
Intermediate uveitis is inflammation of the ciliary body, pars plana, and anterior vitreous.
Posterior uveitis is inflammation of any combination of the following: the choroid (choroiditis), retina (retinitis), or optic nerve head (papillitis).
Panuveitis is inflammation in both the anterior and posterior chambers.
Most uveitis is idiopathic.; however, when a cause is identified, it usually includes one of the following: systemic autoimmune disorders, infection, trauma, or neoplasia.
The major causes of visual loss in people with uveitis are cystoid macular oedema, secondary cataract, and secondary glaucoma.
Symptoms may develop over hours or days (acute uveitis), or gradually (chronic uveitis). People who have had uveitis before may feel the symptoms coming on before the signs are present.
Uveitis usually resolves rapidly with treatment; however, it is thought that a significant number of people may develop persistent disease, which may cause severe visual impairment.
Clinical features include:
Pain in one or both eyes (pain may be worse when contracting the ciliary muscle such as when reading).
Red eye (not always present).
Diminished or blurred vision (although vision may be normal but become impaired later).
Watering of the eye.
Photophobia.
Flashes and floaters.
An unreactive or irregular-shaped pupil resulting from previous attacks.
Alternative diagnoses include acute glaucoma, keratitis, scleritis, and ocular trauma.
If uveitis is suspected (new presentations and recurrent), the person should be referred to an ophthalmologist for same-day assessment to confirm the diagnosis. Uveitis cannot be diagnosed without slit-lamp examination.
Treatment for uveitis should not be initiated in primary care unless asked to do so by an ophthalmologist.
For non-infectious uveitis, corticosteroids are used to reduce inflammation and prevent adhesions in the eye. A cycloplegic-mydriatic drug (e.g. cyclopentolate 1%) is also given to paralyse the ciliary body.
For infectious uveitis (bacterial, viral, fungal, or parasitic), an appropriate antimicrobial drug as well as corticosteroids and cycloplegics are used.
People with severe or chronic uveitis may also be given systemic (non-corticosteroid) immunosuppressive drugs, laser phototherapy, or cryotherapy, or have the vitreous removed surgically.
If treatment is initiated by an ophthalmologist, primary healthcare professionals may be asked to:
Monitor for adverse effects of treatments (e.g. oral corticosteroids).
Monitor the use of disease-modifying antirheumatic drugs (DMARDs) or immunosuppressants, depending on locally-agreed shared care guidelines.
Ensure that people receiving repeat prescriptions of topical corticosteroids are under the care of an ophthalmologist (to monitor for steroid-induced glaucoma).
Have I got the right topic?
This CKS topic covers the management of suspected uveitis in primary care.
This CKS topic does not cover the management of other causes of red eye.
There are separate CKS topics on Blepharitis, Conjunctivitis - allergic, Conjunctivitis - infective, Corneal superficial injury, Dry eye syndrome, Herpes simplex - ocular, Red eye, and Retinal detachment.
The target audience for this CKS topic is healthcare professionals working within the NHS in the UK, and providing first contact or primary health care.
How up-to-date is this topic?
How up-to-date is this topic?
Changes
March 2010 — minor typographical correction. Issued in March 2010.
July to November 2009 — this is a new CKS topic. The evidence-base has been reviewed in detail, and recommendations are clearly justified and transparently linked to the supporting evidence.
Update
New evidence
Evidence-based guidelines
No new evidence-based guidelines since 1 July 2009.
HTAs (Health Technology Assessments)
No new HTAs since 1 July 2009.
Economic appraisals
No new economic appraisals relevant to England since 1 July 2009.
Systematic reviews and meta-analyses
Systematic reviews published since the last revision of this topic:
Barisani-Asenbauer, T., Macam S.M., Mejdoubi, L., et al. (2012) Uveitis - a rare disease often associated with systemic disease and infections - a systematic review of 2619 patients. Orphanet Journal of Rare Diseases 7(1), 57. [Abstract] [Free Full-text]
Primary evidence
No new randomized controlled trials published in the major journals since 1 July 2009.
Observational studies published since the last revision of this topic:
Nguyen, Q.D., Hatef, E., Kayen, B., et al. (2010) A cross-sectional study of the current treatment patterns in noninfectious uveitis among specialists in the United States. Ophthalmology 118(1), 184-190. [Abstract]
New policies
No new national policies or guidelines since 1 July 2009.
New safety alerts
No new safety alerts since 1 July 2009.
Changes in product availability
No changes in product availability since 1 July 2009.
Goals and outcome measures
Goals
To recognize uveitis in its early stages and refer for same-day specialist assessment
Background information
Definition
What is it?
Uveitis (also known as iritis) is inflammation of the uveal tract (iris, ciliary body, and choroid). Inflammation of nearby tissues, such as the retina, the optic nerve, and the vitreous humour, may also occur [Rathinam and Namperumalsamy, 2007; Forster, 2009].
See Wikipedia for a cross-sectional diagram of the eye.
Uveitis is a potentially blinding condition that accounts for approximately 10% of people with visual impairment in the western world [Wakefield and Chang, 2005].
Uveitis can be classified based on which part of the eye is affected by the inflammation [Bloch-Michel and Nussenblatt, 1987; Merck, 2008].
Anterior uveitis (the most common form of uveitis) — inflammation in the anterior segment of the eye; this includes iritis (inflammation that is confined to the anterior chamber) and iridocyclitis (inflammation that is confined to the anterior chamber and anterior vitreous).
Intermediate uveitis — inflammation of the ciliary body, pars plana, and anterior vitreous.
Posterior uveitis — inflammation of any combination of the following: the choroid (choroiditis), retina (retinitis), or optic nerve head (papillitis).
Panuveitis — inflammation in both the anterior and posterior chambers.
Uveitis may be acute, recurrent, or chronic [Jabs et al, 2005].
Acute — sudden onset of inflammation which resolves within 3 months.
Recurrent — repeated episodes, separated by periods of inactivity without treatment for more than 3 months.
Chronic — persistent inflammation lasting more than 3 months, in which prompt relapse (within 3 months) occurs when treatment is discontinued.
Causes
What causes it?
In many cases, the cause of uveitis is not known; when a cause is identified, it usually includes one of the following [Merck, 2008; Forster, 2009]:
Systemic autoimmune disorders, such as:
Seronegative spondyloarthropathies (ankylosing spondylitis, juvenile rheumatoid arthritis, Reiter's syndrome, and inflammatory bowel disease).
Behçet's disease.
Sarcoidosis.
Psoriasis (with or without associated arthritis).
Multiple sclerosis.
Infection.
Common infectious causes are herpes simplex, varicella-zoster virus, cytomegalovirus, and toxoplasmosis.
Less common infectious causes include histoplasmosis, Lyme disease, syphilis, toxocariasis, and tuberculosis.
Rare infectious fungal causes include Aspergillus and Candida.
Trauma.
Neoplasia (rare).
In developed countries [Forster, 2009]:
Most uveitis is idiopathic and thought to be autoimmune in origin.
Only a minority of people with uveitis have an infectious cause.
Some people go on to develop chronic uveitis. The reason for this is unknown, but it is not thought to be due to poor treatment [Gupta and Murray, 2006].
Prevalence
How common is it?
The annual incidence of uveitis is 17–52 per 100,000 people, and the prevalence is 38–714 per 100,000 people [Wakefield and Chang, 2005].
Uveitis usually affects people 20–59 years of age; however, it can occur at any age. It is less common in children younger than 16 years of age [Wakefield and Chang, 2005].
Men and women are equally affected by uveitis [Wakefield and Chang, 2005].
Risk factors
What are the risk factors?
Factors known to increase the risk of uveitis include [Khaw et al, 2004; Gupta and Murray, 2006]:
A history of uveitis.
A seronegative spondyloarthropathy, such as:
Ankylosing spondylitis.
Reactive arthritis (including Reiter's syndrome).
Psoriatic arthritis.
Inflammatory bowel disease.
Juvenile rheumatoid arthritis — children with a seronegative arthritis are at high risk, particularly if the arthritis affects only a few joints (pauciarticular) [Khaw et al, 2004].
The HLA-B27 antigen — this is present in approximately 10% of the general population and in about 50% of white people with acute anterior uveitis [Wakefield and Chang, 2005].
Complications
What are the complications?
About 10% of the visual impairment in the western world is thought to be caused by uveitis. Up to 35% of all people with uveitis worldwide have been reported to have significant visual impairment or legal blindness (visual acuity of 20/200 [6/60] or less in the better eye with the best correction possible) [Pugh, 2000; Wakefield and Chang, 2005].
The major causes of vision loss in people with uveitis are cystoid macular oedema, secondary cataract, and secondary glaucoma [Gupta and Murray, 2006].
Other vision-threatening complications include [Forster, 2009]:
Band keratopathy (calcium deposits in the cornea).
Posterior synechiae (adhesions between posterior iris and the anterior lens surface).
Hypotony (low intraocular pressure).
Macular hole.
Macular ischaemia.
Retinal detachment (exudative and tractional).
Choroidal and retinal neovascularization.
Optic neuropathy.
Optic atrophy.
Vitreous opacities.
Retinal scars.
Phthisis (shrinkage of the globe).
Prognosis
What is the prognosis?
Uveitis usually resolves rapidly with treatment; however, it is thought that a significant number of people may develop persistent disease, which may cause severe visual impairment [Gupta and Murray, 2006]. The proportion of people who go on to develop chronic disease is not currently known.
Continued inflammation may lead to permanent damage of the trabecular meshwork, secondary glaucoma, cataracts, and oedema of the macula [Khaw et al, 2004].
Acute anterior uveitis has the best visual outcome; people with chronic anterior uveitis, posterior uveitis, and panuveitis have a worse visual prognosis [Gutteridge and Hall, 2007].
Permanent vision loss may occur following [Gutteridge and Hall, 2007]:
Late detection.
Delayed treatment.
Poor control of inflammation.
Damage from recurrent attacks.
Diagnosis
Diagnosis of uveitis
When to suspect uveitis
When should I suspect uveitis?
Clinical features of uveitis vary depending on the location of the inflammation. They include:
Pain in one or both eyes (pain may be worse when the person is reading and otherwise contracting the ciliary muscle).
Red eye (this is not always present).
Diminished or blurred vision (although vision may be normal but become impaired later).
Watering of the eye.
Photophobia.
Flashes and floaters.
An unreactive or irregular-shaped pupil resulting from previous attacks (although this is not easy to see in primary care).
Symptoms may develop over hours or days (acute uveitis), or onset may be gradual (chronic uveitis).
If the person has had uveitis before, they may feel the symptoms coming on before the signs are present.
People with chronic uveitis are more likely to experience milder inflammatory symptoms:
Mildly red eye or normal-looking eye.
Mild pain with photophobia.
Uveitis is more likely if the person has risk factors for uveitis (for example a history of attacks) and other eye conditions have been excluded.
If uveitis is suspected, refer the person to an ophthalmologist for same-day assessment to confirm the diagnosis and for treatment.
Uveitis cannot be diagnosed without slit-lamp examination.
Slit-lamp examination will show inflammatory cells that may aggregate to form 'snowballs'.
Basis for recommendation
Basis for recommendation
When to suspect uveitis
The information on when to suspect uveitis is based on two standard reference textbooks, Ophthalmology [Forster, 2009] and ABC of eyes [Khaw et al, 2004], and published expert opinion [Gupta and Murray, 2006; Gutteridge and Hall, 2007].
Symptoms and signs vary depending on the location of the inflammation
The statement in that symptoms and signs vary depending on the location of the inflammation is based on expert opinion from an online textbook [Merck, 2008].
Findings on slit-lamp examination
The statement that slit-lamp examination will show inflammatory cells, which may aggregate to form 'snowballs' is derived from a textbook [Moorthy and Jampol, 2009; Tsai and Rao, 2009].
Differential diagnosis
What else might it be?
Other serious sight-threatening conditions:
Acute glaucoma — causes markedly increased intraocular pressure; it presents with pain in the eye, headache, and blurring of vision. Signs include:
Ciliary injection.
Eye feels rock hard and very painful.
Fixed and mid-dilated pupil.
Hazy cornea.
Headache and vomiting.
Markedly diminished vision.
Keratitis — presents with a unilateral, painful, photophobic, injected eye. Signs include:
Ciliary injection.
Corneal ulceration — often seen as a white spot (ulcer may be dendritic when caused by herpes simplex).
Visual impairment may be affected, depending on the site of the ulcer.
Scleritis — characterized by severe pain. It is usually associated with headache; autoimmune diseases, such as rheumatoid arthritis and systemic lupus erythematosus; infections (rarely); and chemical injuries (rarely).
Ocular trauma
Penetrating eye injury or embedded foreign body.
Acid or alkali burns to the eye.
Non-sight-threatening causes
Episcleritis — this is painful but essentially self limiting. Scleritis is much more serious.
Infective conjunctivitis — this is more likely when:
There is a history of close contact with another affected person.
Symptoms of upper respiratory tract infection are present.
The eyes are glued together by discharge after sleep, or mucopurulent discharge is seen on examination.
Symptoms start in one eye then spread to the other.
An enlarged lymph node in front of the ear is identified.
Irritant conjunctivitis is likely when conjunctivitis is associated with an identifiable mechanical or irritant cause, such as a displaced contact lens, a foreign body or eyelashes rubbing against the surface of the eye, or a chemical splashing into the eye.
Allergic conjunctivitis is likely when conjunctivitis is associated with itching and recurs after exposure to a known allergen.
Superficial corneal injury is likely when eye pain follows trauma or possible trauma, and a foreign body is present. It is confirmed when an abrasion is seen after staining with fluorescein.
Subconjunctival haemorrhage is asymptomatic and, other than redness, there are no other abnormal findings. The redness is well demarcated, does not cover the cornea, and obliterates conjunctival blood vessels.
Rare neoplastic syndromes which mimic intraocular inflammation (masquerade syndromes), such as:
Lymphoma.
Leukaemia.
Ocular melanoma.
Metastases.
[Khaw et al, 2004; Yanoff and Duker, 2004; Gupta and Murray, 2006]
Management
Management
Scenario: Management: covers the primary care management of people with suspected uveitis.
Scenario: Management
Scenario: Management of uveitis
Suspected uveitis
How do I manage a person with suspected uveitis in primary care?
Refer people with suspected uveitis (new presentations and recurrent) for assessment within 24 hours by an ophthalmologist.
This includes people who have had uveitis before and feel the symptoms coming on before the signs are present.
Do not initiate treatment for recurrent uveitis in primary care, unless asked to do so by an ophthalmologist.
Additional information
Treatment in secondary care
Non-infectious uveitis
Corticosteroids are used to reduce inflammation and prevent adhesions in the eye. They may be given topically, orally, intravenously, intramuscularly, or by periocular or intraocular injection, depending on how severe the uveitis is [Gupta and Murray, 2006]. Corticosteroids are tapered slowly (over weeks) because withdrawing them too quickly may lead to rebound inflammation [Gupta and Murray, 2006].
A cycloplegic-mydriatic drug (for example cyclopentolate 1% or atropine 1%) is also given to paralyse the ciliary body. This relieves pain and prevents adhesions between the iris and lens [Khaw et al, 2004].
Infectious uveitis
Infectious uveitis (bacterial, viral, fungal, or parasitic) is treated with an appropriate antimicrobial drug as well as corticosteroids and cycloplegics [Durand, 2005].
People with severe or chronic uveitis may also be given systemic (non-corticosteroid) immunosuppressive drugs, laser phototherapy, or cryotherapy, or have the vitreous removed surgically (vitrectomy) [Merck, 2008].
Basis for recommendation
Basis for recommendation
Referral is recommended because:
Uveitis cannot be diagnosed without slit-lamp examination.
Uveitis usually resolves quickly with treatment; however, if it is not treated or is inadequately treated, it may result in profound and irreversible vision loss [Gupta and Murray, 2006; Merck, 2008].
Treatment with corticosteroids should not be prescribed before the diagnosis has been confirmed by slit-lamp examination. If the person has herpes simplex virus infection corticosteroids can transform a simple herpetic dendritic ulcer into an extensive amoeboid ulcer involving all layers of the cornea, with resultant corneal scarring and visual loss [Frith et al, 2001].
Recurrent or chronic uveitis
How do I manage someone with recurrent or chronic uveitis in primary care?
Refer people with recurrent or chronic uveitis to an ophthalmologist for each episode, to confirm the diagnosis and treatment.
Do not initiate treatment, unless asked to do so by an ophthalmologist.
Uveitis should be managed by an ophthalmologist; however, primary healthcare professionals:
May be asked to monitor the person for adverse effects of long-term oral corticosteroids (continuous or repeated courses).
May be asked to monitor the use of disease-modifying antirheumatic drugs (DMARDs) or immunosuppressants, depending on locally-agreed shared care guidelines. For more information, see the CKS topic on DMARDs.
Should ensure that people receiving repeat prescriptions of topical corticosteroids are under the care of an ophthalmologist (to monitor for steroid-induced glaucoma).
Additional information
Managing the adverse effects of systemic corticosteroids
Adverse effects of systemic corticosteroids include:
Gastrointestinal toxicity: consider prescribing gastrointestinal protection. Peptic ulceration with perforation and haemorrhage, dyspepsia, abdominal distention, and oesophageal ulceration have been reported.
Osteoporosis: see the CKS topic on Osteoporosis - steroid-induced for details on when to prescribe prophylactic bisphosphonate therapy.
Blood pressure: monitor annually and treat if necessary. See the CKS topic on Hypertension - not diabetic for more information.
Diabetes mellitus: screen every 6–12 months and treat if necessary. See the CKS topic on Diabetes - type 2 for more information.
Glaucoma: screening is usually conducted within 3 months of starting corticosteroids and annually thereafter.
Adrenal insufficiency: gradually taper (reduce) the dose after prolonged systemic corticosteroid treatment to prevent potentially fatal acute adrenal insufficiency.
Immunosuppression: document the person's history of chickenpox or measles. Advise those without a history of chickenpox or measles who are taking systemic prednisolone to avoid close contact with people who have chickenpox, shingles, or measles and to seek urgent medical advice if they are exposed.
Psychiatric effects (such as mood changes, depression, suicidal thoughts, or feeling high) can occur within a few days or weeks after the start of treatment in up to 5–6% of people. Seek specialist advice if psychiatric adverse effects occur. Most people recover from these reactions after dose reduction or withdrawal, although specific treatment might be necessary.
Basis for recommendation
Basis for recommendation
Referral is recommended because:
Uveitis cannot be diagnosed without slit-lamp examination.
Uveitis usually resolves quickly with treatment; however, if it is not treated or is inadequately treated, it may result in profound and irreversible vision loss [Gupta and Murray, 2006; Merck, 2008].
Treatment with corticosteroids should not be prescribed before the diagnosis has been confirmed by slit-lamp examination. If the person has herpes simplex virus infection corticosteroids can transform a simple herpetic dendritic ulcer into an extensive amoeboid ulcer involving all layers of the cornea, with resultant corneal scarring and visual loss [Frith et al, 2001].
Managing the adverse effects of systemic corticosteroids
These recommendations are based on published information from manufacturers [ABPI Medicines Compendium, 2009], best medical practice, and advice issued by the Medicines and Healthcare products Regulatory Agency [MHRA, 2007a; MHRA, 2007b].
The risk and severity of adverse effects with oral corticosteroids increase with the dose and the duration of treatment.
Evidence
Evidence
Supporting evidence
There is no supporting evidence section within this CKS topic because:
The recommendations for when to suspect uveitis and how to manage suspected uveitis are based on published expert opinion rather than trial-based evidence.
The evidence for the treatments of uveitis has not been reviewed, as these are initiated by specialists and are therefore beyond the scope of this CKS topic.
Search strategy
Scope of search
A literature search was conducted for guidelines, systematic reviews and randomized controlled trials on the primary care management of uveitis with additional searches in the following areas:
When to suspect uveitis, differential diagnosis.
When to refer.
Search dates
Medline and Embase: January 1990 – August 2009
Key search terms
Various combinations of searches were carried out. The terms listed below are the core search terms that were used for Medline and these were adapted for other databases. Further details are available on request.
exp Uveitis/, exp Uveitis, Anterior/, exp Uveitis, Suppurative/, exp Uveitis, Posterior/, exp Uveitis, Intermediate/
Table 1. Key to search terms.| Search commands | Explanation |
|---|---|
| / | indicates a MeSH subject heading with all subheadings selected |
| .tw | indicates a search for a term in the title or abstract |
| exp | indicates that the MeSH subject heading was exploded to include the narrower, more specific terms beneath it in the MeSH tree |
| $ | indicates that the search term was truncated (e.g. wart$ searches for wart and warts) |
Topic specific literature search sources
American Academy of Ophthalmology
Royal College of Ophthalmologists
Sources of guidelines
National Institute for Health and Clinical Excellence (NICE)
Scottish Intercollegiate Guidelines Network (SIGN)
Royal College of General Practitioners
National Guidelines Clearinghouse
Institute for Clinical Systems Improvement
Guidelines International Network
NHS Evidence - National Library of Guidelines
National Health and Medical Research Council (Australia)
Royal Australian College of General Practitioners
National Resource for Infection Control
NHS Scotland National Patient Pathways
Agency for Healthcare Research and Quality
UK Ambulance Service Clinical Practice Guidelines
RefHELP NHS Lothian Referral Guidelines
Medline (with guideline filter)
British Columbia Medical Association
University of Michigan Medical School
Michigan Quality Improvement Consortium
Sources of systematic reviews and meta-analyses
Systematic reviews
Protocols
Database of Abstracts of Reviews of Effects
Medline (with systematic review filter)
EMBASE (with systematic review filter)
Sources of health technology assessments and economic appraisals
NIHR Health Technology Assessment programme
NHS Economic Evaluations
Health Technology Assessments
Canadian Agency for Drugs and Technologies in Health
International Network of Agencies for Health Technology Assessment
Sources of randomized controlled trials
Central Register of Controlled Trials
Medline (with randomized controlled trial filter)
EMBASE (with randomized controlled trial filter)
Sources of evidence based reviews and evidence summaries
DynaMed
Central Services Agency COMPASS Therapeutic Notes
Sources of national policy
Health Management Information Consortium (HMIC)
References
ABPI Medicines Compendium (2009) Summary of product characteristics for Deltacortril gastro-resistant tablets. Electronic Medicines Compendium..Datapharm Communications Ltd.www.medicines.org.uk
Bloch-Michel, E. and Nussenblatt, R.B. (1987) International Uveitis Study Group recommendations for the evaluation of intraocular inflammatory disease. American Journal of Ophthalmology 103(2), 234-235.
Durand, M.L. (2005) Chapter 109: infectious causes of uveitis. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases - Online.6th edn.Elsevier.www.ppidonline.com
Forster, D.J. (2009)
Frith, P., Gray, R., MacLennan, A.H. and Ambler, P. (Eds.) (2001) The eye in clinical practice. 2nd edn. London: Blackwell Science.
Gupta, R. and Murray, P.I. (2006) Chronic non-infectious uveitis in the elderly: epidemiology, pathophysiology and management. Drugs & Aging 23(7), 535-558. [Abstract]
Gutteridge, I.F. and Hall, A.J. (2007) Acute anterior uveitis in primary care. Clinical & Experimental Optometry 90(2), 70-82. [Abstract]
Jabs, D.A., Nussenblatt, R.B., Rosenbaum, J.T. and Standardization of Uveitis Nomenclature (SUN) Working Group (2005) Standardization of uveitis nomenclature for reporting clinical data. Results of the First International Workshop. American Journal of Ophthalmology 140(3), 509-516. [Abstract]
Khaw, P.T., Shah, P. and Elkington, A.R. (Eds.) (2004) ABC of eyes. 4th edn. London: BMJ Books.
Merck (2008) Uveitis. Merck Manual..MERCK.www.merck.com [Free Full-text]
MHRA (2007a) Steroids: ten questions and answers for patients. ..Medicines and Healthcare products Regulatory Agency.www.mhra.gov.uk [Free Full-text]
MHRA (2007b) Corticosteroids: early psychiatric side-effects. Drug Safety Update 1(2), 9-10. [Free Full-text]
Moorthy, R.S. and Jampol, L.M. (2009)
Pugh, M. (Ed.) (2000) Stedman's medical dictionary. 27th edn. Baltimore, MD: Lippincott Williams & Wilkins.
Rathinam, S.R. and Namperumalsamy, P. (2007) Global variation and pattern changes in epidemiology of uveitis. Indian Journal of Ophthalmology 55(3), 173-183. [Abstract] [Free Full-text]
Tsai, J.H. and Rao, N.A. (2009)
Wakefield, D. and Chang, J.H. (2005) Epidemiology of uveitis. International Ophthalmology Clinics 45(2), 1-13.
Yanoff, M. and Duker, J.S. (Eds.) (2004) Ophthalmology. 2nd edn. St. Louis: Mosby.