Uveitis

Aka: Uveitis, Iritis, Anterior Uveitis, Iridocyclitis, Intermediate Uveitis, Posterior Uveitis, Neuroretinitis, Panuveitis, Corneal Keratic Precipitate, Keratic Precipitate

1. See Also
   1. See Medication Causes of Uveitis
2. Defintions
   1. Uveitis
      1. Uveal tract inflammation
      2. Defined as chronic if duration more than 3 months
3. Epidemiology
   1. Incidence: 17 to 52 per 100,000 per year in North America
   2. Prevalence: 58 to 115 per 100,000 per year in North America
   3. Peak ages: 20-59 years old
4. Pathophysiology
   1. Autoimmune reaction (similar to Episcleritis and Scleritis)
   2. Uveitis may occur in isolation or as part of a systemic inflammatory condition (see causes below)
   3. Diagnosis is as a result of spillover inflammation into the aqueous and vitreous resulting in cells and flare
5. Types
   1. Anterior Uveitis (Iritis or Iridocyclitis)
      1. Inflammation of iris of the uveal tract (and the ciliary muscle) in the anterior chamber
      2. When the ciliary muscle/body is involved it is known as Iridocyclitis
      3. May occur from spillover inflammation from the Cornea (keratouveitis) or Sclera (sclerouveitis)
   2. Intermediate Uveitis
      1. Inflammation of the vitreous chamber (vitritis)
   3. Posterior Uveitis
      1. Inflammation of the Retina (retinitis) or Choroid (Choroiditis or chorioretinitis)
      2. May extend to the Optic Nerve head (Neuroretinitis)
   4. Panuveitis
      1. Generalized ocular inflammation
6. Causes
   1. See Medication Causes of Uveitis
   2. Blunt Eye Trauma
   3. Bacterial Infection
      1. See Endophthalmitis under differential diagnosis below
      2. Bloodbourne infection
         1. Involves any uveal location
      3. Cat-Scratch Disease
         1. Involves Posterior Uveitis, specifically Neuroretinitis
      4. Lyme Disease
         1. Involves any uveal location
      5. Mycobacterium tuberculosis
         1. Involves any uveal location
         2. Affects <1% of Tb cases
      6. Syphilis
         1. Involves any uveal location
         2. Affects <5% of Syphilis cases
      7. Toxocariasis
         1. Involves posterior uveal location (Posterior Uveitis)
      8. Leprosy
   4. Other infectious causes
      1. Local infection from perforating wound or Corneal Ulcer
      2. Viral Exanthem
      3. HIV Infection
   5. Rheumatologic Conditions
      1. Rheumatoid Arthritis
         1. Occurs in up to 50% of pauciarticular Juvenile Rheumatoid Arthritis
            1. Accounts for 80% of Uveitis cases in children
         2. Occurs in <5% of adult Rheumatoid Arthritis
            1. Typically a result of Scleritis or Keratitis spill-over
      2. Spondyloarthropathy (often seronegative, affects Anterior Uveitis)
         1. Ankylosing Spondylitis
         2. Reiter's Syndrome (Reactive Arthritis)
         3. Psoriatic Arthritis
      3. Behcet's Disease
         1. May affect any uveal location
         2. Occurs in >60% of cases
      4. Relapsing Polychondritis
         1. Involves anterior chamber (Anterior Uveitis)
      5. Sarcoidosis
         1. Involves any uveal location
      6. Systemic Lupus Erythematosus (SLE)
         1. Involves any uveal location
         2. Affects <1% of SLE cases
      7. Vogt-Koyanagi-Harada Syndrome
         1. Involves Posterior Uveitis
         2. Uveitis occurs in 100% of cases
      8. Kawasaki's Disease
   6. Inflammatory Bowel Disease (Anterior Uveitis, affecting >15% of IBD cases)
      1. Ulcerative Colitis
      2. Crohn's Disease
   7. Neurologic disorders
      1. Multiple Sclerosis (Intermediate Uveitis, affecting 30% of MS cases)
   8. Renal disorders
      1. Tubular Interstitial Nephritis
         1. Involves anterior chamber (Anterior Uveitis)
7. Symptoms
   1. Eye Pain
      1. Moderate deep aching sensation
      2. May radiate into periocular structures (e.g. brow pain or temporal pain)
      3. Eye Pain is often absent in Intermediate Uveitis and Posterior Uveitis
   2. Photophobia
   3. Vision decreased or blurred
   4. Visual Floaters
8. Signs
   1. Pupil constricted and poorly reactive (due to iris spasm)
      1. Other acute eye conditions typically cause Mydriasis
   2. Conjunctival injection
      1. Present in most cases of Anterior Uveitis
   3. Ciliary Flush (or blush)
      1. Injection of bulbar Conjunctiva around limbus (circumcorneal hyperemia)
   4. Anterior flare
      1. Flare is an increased turbidness or cloudiness of the Aqueous Humor
   5. Anterior chamber "cells" slough
      1. Anterior cells seen on Slit Lamp exam
      2. Often in combination with flare (known as "cells and flare")
   6. Corneal Keratic Precipitates
      1. Yellow or white deposits of aggregated cells on the posterior surface of the Cornea (endothelial surface)
      2. Results from the anterior chamber cells
   7. Sterile Hypopyon
      1. White Blood Cells in severe inflammatory response may settle and accumulate at the anterior chamber floor
   8. Irregular pupil shape
      1. Iris may adhere to adjacent structures (anterior lens or posterior Cornea)
   9. Intraocular Pressure abnormal
      1. May be either increased or decreased
9. Labs
   1. First-line labs to consider if systemic cause is suspected
      1. Complete Blood Count
      2. Basic metabolic panel
      3. Urinalysis
      4. Erythrocyte Sedimentation Rate (ESR)
      5. C-Reactive Protein (CRP)
   2. Other tests to consider
      1. Rapid Plasma Reagin (RPR)
      2. Tuberculin Skin Test or Quantiferon-TB
      3. HLA-B27 (if Spondyloarthropathy suspected)
      4. Other rheumatologic of infectious disease tests as indicated based on history and exam
10. Imaging
    1. Chest XRay
       1. Consider if Sarcoidosis, Tuberculosis suspected
11. Differential Diagnosis
    1. See Acute Red Eye
    2. Acute Glaucoma
    3. Primary ocular Lymphoma
       1. Consider in age over 50 years old with intermediate or Posterior Uveitis
    4. Endophthalmitis
       1. Bloodborne infection with intraocular infection
       2. Patients typically present appearing toxic or septic
       3. Some cases may develop more insidiously
          1. KlebsiellaPneumoniae in diabetic patients
          2. Systemic Fungal infections
          3. Less virulent Bacterial Infections (e.g. Central Line infection, IV Drug Abuse)
12. Complications
    1. Decreased Visual Acuity
       1. Severe Visual Impairment: 35%
       2. Legally blind: 10%
    2. Iris scarring
       1. Impaired pupillary movement
       2. Secondary Glaucoma
13. Precautions
    1. Children be asymptomatic with minimal exam findings despite significant inflammation (e.g. juvenile RA)
    2. Intermediate and Posterior Uveitis may have relatively normal anterior chambers
    3. Most Uveitis findings require the magnification of a Slit Lamp exam
14. Management
    1. Urgent referral all cases to Ophthalmology
       1. Risk of serious complications if delayed management
    2. Timely Pupillary dilatation
    3. Topical Corticosteroids may be indicated (based on ophthalmology evaluation)
15. References
    1. Rosenbaum in Yanoff (1999) Ophthalmology, p. 4.1
    2. Trobe (2012) Physician's Guide to Eye Care, AAO, p. 67-8
    3. Harman (2014) Am Fam Physician 90(10): 711-6 [PubMed]