Makindo Medical Notes.com

Related Subjects: |Episcleritis |Scleritis |Assessing a Red eye |Acute Angle Closure Glaucoma |Allergic and Infective Conjunctivitis |Anterior and Posterior Uveitis

Uveitis comes from the Latin word uva, meaning grape. If recent intraocular surgery, (e.g. cataract or injections), consider endophthalmitis as the cause of pain and photophobia |

About

• Inflammation of the middle tract of the iris, ciliary body and uveal tract
• Trauma or iatrogenic sources, infectious agent, medications
• Systemic autoimmune condition or idiopathic causes
• Anterior uveitis can affects young patients with potentially long-lasting sight-threatening complications

Epidemiology

• 50% of cases are idiopathic
• Uveitis can occur at any age, but the average age at presentation is about 40
• Anterior uveitis causes 90% of cases of uveitis

Types

• Anterior Uveitis: involves the iris(iritis),anterior ciliary body(cyclitis),or both (iridocyclitis)
• Posterior uveitis : choroid(choroiditis),retina (retinitis),both( chorioretinitis),or retinal vessels(retinal vasculitis)
• Intermediate uveitis
• Panuveitis uveitis

Aetiology: 50% of cases are idiopathic

• Idiopathic: Anterior uveitis with the HLA-B27 haplotype
• Trauma, including penetrating injury and ophthalmic surgery
• Fuchs’ heterochromic cyclitis
• Posner–Schlossman syndrome
• Rheumatological HLA-B27-associated Ank spondylitis, Psoriatic, reactive
• Juvenile idiopathic arthritis
• Behçet’s disease
• Polyarteritis nodosa
• Granulomatosis with polyangiitis (Wegener’s)
• Brucellosis
• Herpesvirus infections(CMV, HSV, VZV)
• Leptospirosis, Lyme borreliosis, Syphilis
• Toxoplasmosis, Tuberculosis
• Whipple’s disease, Crohn’s disease, ulcerative colitis)
• Primary central nervous system lymphoma (rare)
• Multiple sclerosis, Sarcoidosis

Clinical

• Severe eye pain with tearing. Small pupil due to iris spasm
• Anterior uveitis: diffuse redness most marked at limbus
• anterior chamber may appear cloudy from suspended white blood cells and flare.
• Look closely for a hypopyon.
• Limbal flush, posterior synechiae and Anterior chamber cells
• Assess visual acuity which may be reduced
• Flare observed on slit-lamp biomicroscopy see below
• Assess the cornea for white cell infiltrates (small white opacities indicating bacterial infection).
• Check for fluorescein staining and intraocular pressure

Investigations

• Slit lamp biomicroscopy: are cells and “flare" (protein) in the anterior chamber. The inner surface of the cornea may be speckled with keratic precipitates that either fine (“granular") or globular (“granulomatous" or “mutton fat" keratic precipitates)
• PCR has proven most helpful in herpetic uveitis cases, such as herpetic anterior uveitis and ARN
• Investigations for systemic disease - TB and other infections and autoimmune diseases etc.

Differentials

• Endophthalmitis
• Uveitis (iritis)
• Severe corneal inflammation from bacterial or viral infection, or chemical burn
• Intraocular foreign bod

Complications

• Glaucoma
• Cataracts
• Corneal complications
• Systemic side effects

Management: Refer early to ophthalmology. They may Dilate pupil and give steroids

• Suspected Endophthalmitis requires immediate phone referral, as do most corneal conditions.
• Idiopathic Anterior uveitis: Acutely, dilating drops prevent the inflamed iris from sticking to the lens (posterior synechiae) and obstructing the outflow of aqueous fluid. Given with a reducing dose of topical glucocorticoids, usually over 4–6 weeks
• Management of AAU is focused on reducing the inflammation and any associated pain, redness, photophobia and visual blur and determining the aetiology.
• Sun protection: avoidance of bright light is to their immediate benefit. Encouragement of sunglasses, a brimmed hat, staying indoors more frequently and lowered lighting levels are good behavioural modifications during the acute symptomatic stage.
• Cycloplegics: Cycloplegic agents are important for relaxing the iris (for comfort), breaking posterior synechiae, and stabilizing the blood-aqueous barrier by decreasing the iris surface area (preventing further cellular and exudative leakage). The most popular agents used in AAU treatment are homatropine 5% or scopolamine 0.25%. Atropine is used in more severe cases. They will enlarge pupils and temporarily blur vision, especially when reading
• Mydriatics: Phenylephrine is an adrenergic(alpha receptor) agonist used for assisting with the dilation of the pupil. It is used in-office with a cycloplegic agent for breaking recalcitrant posterior synechiae. Usually, only one or two drops are instilled in the affected eye to facilitate dilation. The drug also assists in facilitating view of the vitreous and retina, to determine if there is any posterior segment inflammation.
• Corticosteroids: Corticosteroids are critical in the treatment of uveitides, including AAU. They reduce pain (including photophobia), inflammation(of most ocular tissues) and redness(of conjunctiva, episclera, limbus).Corticosteroids block the enzyme phospholipase A2 (which converts cell membrane phospholipids into inflammatory mediators such as leukotrienes and prostaglandins).
• Herpetic anterior uveitis is treated primarily with topical corticosteroids. Oral acyclovir should be started as well because long term prophylactic oral Aciclovir(400 mg twice daily)

References

• Management and treatment
• Case reports