Uveitis

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      • Anatomic Classification
        • Anterior uveitis.
          • It is inflammation of the uveal tissue from iris up to pars plicata of ciliary body.
          • It may be subdivided into
            • Iritis, in which inflammation predominantly affects the iris.
            • Iridocyctitis in which iris and pars plicata part of ciliary body are equally involved
            • Cyclitis, in which pars plicata part of ciliary body is predominantly affected.
        • Intermediate uveitis.
          • It includes inflammation of the pars plana and peripheral part of the retina and underlying ‘choroid’.
          • It is also called ‘pars planitis’.
        • Posterior uveitis.
          • It refers to inflammation of the choroid (choroiditis).
          • Always there is associated inflammation of retina and hence the term ‘chorioretinitis’ is used.
          • Panuveitis. It is inflammation of the whole uvea.
      • Clinical classification
        • Acute uveitis.
          • It has got a sudden symptomatic onset
          • the disease lasts for about six weeks to 3 months.
        • Chronic uveitis.
          • It frequently has an insiduous and asymptomatic onset.
          • It persists longer than 3 months to even years
          • usually diagnosed when it causes defective vision.
      • Pathological classification – Wood’s classification
        • Suppurative or purulent uveitis.
        • Non-suppurative uveitis.
          • Non-granulomatous uveitis, and
          • Granulomatous uveitis
      • Etiology of uveitis
        • Types of infectious uveitis. (MCQ)
          • Bacterial infections
            • granulomatous
              • tubercular, leprotic, syphilitic, brucellosis
            • pyogenic
              • streptococci, staphylococci, pneumococci and gonococcus
          • Viral infections associated with uveitis are
            • herpes simplex, herpes zoster and cytomegalo inclusionvirus (CMV).
          • Fungal uveitis
            • systemic aspergillosis
            • candidiasis
            • blastomycosis.
          • Parasitic uveitis
            • toxoplasmosis, toxocariasis, onchocerciasis and amoebiasis.
          • Rickettsial uveitis
            • scrub typhus and epidemic typhus.
      • Allergic (hypersensitivity linked) uveitis.
        • Allergic uveitis is of the commonest occurrence in clinical practice.
        • It may be caused by the following ways
          • Microbial allergy
            • InIndia tubercular infections still play an important role.
          • Anaphylactic uveitis
          • Atopic uveitis.
          • Autoimmune uveitis.
            • It is found in association with autoimmune disorders such as
              • Still’s disease, rheumatoid arthritis, Wegener’ s granulomatosis
              • systemic lupus erythematosus, Reiter’s disease
            • In phacoanaphytic endophthalmitis
              • lens proteins play role of autoantigens
            • sympathetic ophthalmitis
              • autoimmune reaction to uveal pigments
          • HLA-associated uveitis
            • HLA-B27.-ankylosing spondylitis and Reiter’ s syndrome.
            • HLA-B5: Uveitis in Behcet’s disease.
            • HLA-DR4 and DW15: Vogt Koyanagi Harada’s disease (MCQ)
          • Toxic uveitis.
            • Endotoxins,
            • seen in patients with
              • acute pneumococcal or gonococcal conjunctivitis
              • fungal corneal ulcer
            • Endocular toxins
            • Uveitis seen in patients with
              • blind eyes
              • long-standing retinal detachment
              • intraocular haemorrhages
              • intraocular tumours
              • phacotoxic uveitis.
            • Exogenous toxins
            • miotics and cytotoxic drugs are exogenous toxins.
      • Traumatic uveitis.
        • Sympathetic ophthalmia in the other eye.
      • Uveitis associated with non-infective systemic diseases.
        • sarocoidosis
        • collagen related diseases (polyarteritis nodosa (PAN), disseminated lupus erythematosus (DLE), rheumatic and rheumatoid arthritis)
        • metabolic diseases (diabetes mellitus and gout),
        • disease of the central nervous system (disseminated sclerosis)
        • diseases of skin (psoriasis, lichen planus, erythema nodosum, pemphigus)
      • Idiopathic uveitis.
        • Idiopathic specific uveitis entities
          • pars planitis,
          • sympathetic ophthalmitis
          • Fuchs’ hetero-chromic iridocyclitis.
        • Nonspecific idiopathic uveitis entities
          • About more than 25 percent cases of uveitis fall in this group.
      • Pathology of uveitis
        • Pathology of non-granulomatous uveitis.
          • iris
            • becomes waterlogged, oedematous, muddy with blurring of crypts and furrows.
            • its mobility is reduced
          • pupil
            • becomes small in size due to
              • sphincter irritation
              • engorgement of radial vessels of iris.
          • aqueous flare and fine KPs
            • Exudates and lymphocytes poured into the anterior chamber result in
              • aqueous flare (MCQ)
              • deposition of fine KPs at the back of cornea (MCQ)
          • posterior synechiae (MCQ)
            • Due to exudates in the posterior chamber, the posterior surface of iris adheres to the anterior capsule of lens leading to posterior synechiae formation.
          • cyclitic membrane (MCQ)
            • In severe inflammation, due to pouring of exudate from ciliary processes, behind the lens, an exudative membrane called cyclitic membrane may be formed.
          • After healing, pin-point areas of necrosis or atrophy are evident.
          • Subsequent attacks lead to structural changes like atrophy, gliosis and fibrosis which cause adhesions, scarring and eventually destruction of eye.
      • Pathology of granulomatous uveitis.
        • Iris nodules (MCQ)
          • Iris nodules are usually formed near pupillary border (Koeppe’s nodules)( MCQ)
          • characterised by infiltration with lymphocytes, plasma cells, with mobilization and proliferation of large mononuclear cells which eventually become epithelioid and giant cells and aggregate into nodules.
        • mutton fat keratic precipitates (MCQ)
          • Similar nodular collection of the cells is deposited at the back of cornea
        • aqueous flare is minimal.
      • Anterior uveitis (iridocyclitis)
        • Clinical features
          • Main symptoms of acute anterior uveitis are pain, photophobia, redness, lacrimation and decreased vision.
          • In chronic uveitis, however the eye may be white with minimal symptoms even in the presence of signs of severe inflammation.
      • Symptoms
        • Pain.
          • It is dominating symptom of acute anterior uveitis.
          • dull aching throbbing sensation which is typically worse at night.
          • The ocular pain is usually referred along the distribution of branches of fifth nerve, especially towards forehead and scalp.
        • Redness.
          • It is due to circumcorneal congestion
          • occurs as a result of active hyperaemia of anterior ciliary vessels
          • due to the effect of toxins, histamine and histamine-like substances and axon reflex.
        • Photophobia and blepharospasm
          • due to a reflex between sensory fibres of fifth nerve (which are irritated) and motor fibres of the seventh nerve, supplying the orbicularis oculi muscle.
        • Lacrimation
          • occurs as a result of lacrimatory reflex mediated by fifth nerve (afferent) and secretomotor fibres of the seventh nerve (efferent).
        • Defective vision
          • Factors responsible for visual disturbance include
            • induced myopia due to ciliary spasm
            • corneal haze (due to oedema and KPs)
            • aqueous turbidity
            • pupillary block due to exudates
            • complicated cataract
            • vitreous haze
            • cyclitic membrane,
            • associated macular oedema, papillitis or secondary glaucoma
      • Signs
        • Slit lamp biomicroscopic examination is essential to elicit most of the signs of uveitis
      • Lid oedema
      • Circumcorneal congestion
        • marked in acute iridocyclitis and minimal in chronic iridocyclitis.
        • differentiated from superficial congestion occurring in acute conjunctivitis.
      • Corneal signs
        • Corneal oedema
          • due to
            • toxic endothelitis
            • raised intraocular pressure when present.
        • Keratic precipitates (KPs) (MCQ)
          • proteinaceous- cellular deposits occurring at the back of cornea.
          • Mostly, these are arranged in a triangular fashion occupying the centre and inferior part of cornea due to convection currents in the aqueous humour
        • Mutton fat KPs. (MCQ)
          • typically occur in granulomatous iridocyclitis
          • composed of epithelioid cells and macrophages.
          • They are large, thick, fluffy, lardaceous KPs
          • have a greasy or waxy appearance.
          • Mutton fat KPs are usually a few (10 to 15) in number
        • Small and medium KPs (granular KPs). (MCQ)
          • pathognomic of non-granulomatous uveitis
          • composed of lymphocytes.
          • small, discrete, dirty white KPs
          • arranged irregularly at the back of cornea.
          • Small KPs may be hundreds in number and form the so called endothelial dusting.
        • Red KPs.
          • RBCs also take part in composition.
          • seen in haemorrhagic uveitis.
        • Old KPs.
          • These are sign of healed uveitis
          • with healing process KPs shrink, fade, become pigmented and irregular in shape (crenated margins).
          • Old mutton fat KPs usually have a ground glass appearance due to hyalinization.
        • Posterior corneal opacity
          • formed in long- standing cases of iridocyclitis.
      • Anterior chamber signs
        • Aqueous cells.
          • It is an early feature of iridocyclitis.
          • The cells should be counted in an oblique slit-lamp beam,
          • graded as :
            • = 0cells,
            • ± = 1–5 cells,
            • +1 = 6–10 cells,
            • +2 = 11-20 cells,
            • +3 = 21–50 cells, and
            • +4 = over 50 cells
        • Aqueous flare. (MCQ)
          • It is due to leakage of protein particles into the aqueous humour from damaged blood vessels
          • It is demonstrated on the slit lamp examination by a point beam of light passed obliquely to the plane of iris
          • In the beam of light, protein particles are seen as suspended and moving dust particles.
          • This is based on the ‘Brownian movements’ or ‘Tyndal phenomenon’.
          • Aqueous flare is usually (MCQ)
            • marked in nongranulomatous uveitis
            •  minimal in granulomatous uveitis.
          • The flare is graded from ‘0’ to +4. Grade :
            • 0=no aqueous flare
            • +1=just detectable
            • +2=moderate flare with clear iris details
            • +3=marked flare (iris details not clear);
            • +4= intense flare (fixed coagulated aqueous with considerable fibrin).
        • Hypopyon. (MCQ)
          • When exudates are heavy and thick, they settle down in lower part of the anterior chamber as hypopyon (sterile pus in the anterior chamber)
        • Hyphaema (blood in the anterior chamber):
          • seen in haemorrhagic type of uveitis.
        • Changes in depth and shape of anterior chamber
          • occur due to synechiae formation.
        • Changes in the angle of anterior chamber
      • Iris signs
        • Loss of normal pattern.
          • It occurs due to
            • oedema and waterlogging of iris in active phase
            • atrophic changes in chronic phase.
          • Iris atrophy is typically observed in Fuchs’ heterochromic iridocyclitis.(MCQ)
        • Changes in iris colour.
          • muddy in colour during active phase
          • show hyperpigmented and depigmented areas in healed stage.
        • Iris nodules
          • These occur typically in granulomatous uveitis
        • Koeppe’s nodules
          • situated at the pupillary border
          • may initiate posterior synechia.
        • Busacca’s nodules (MCQ)
          • situated near the collarette
          • are large but less common than the Koeppe’s nodules.
        • Posterior synechiae.
          • formed due to organisation of the fibrin-rich exudates.
          • These are adhesions between the posterior surface of iris and
            • anterior capsule of crystalline lens or
            • any other structure which may be
              • artificial lens
              • after cataract
              • posterior capsule (left after extracapsular cataract extraction)
            • anterior hyaloid face.
          • Morphologically, posterior synechiae may be segmental, annular or total.
            • Segmental posterior synechiaerefers to adhesions of iris to the lens at some points
            • Annular posterior synechiae
              • ring synechiae are 360o adhesions of pupillary margin to anterior capsule of lens.
              • seclusio pupillae (MCQ)
                • These prevent the circulation of aqueous humour from posterior chamber to anterior chamber
              • ‘iris-bombe’ (MCQ)
                • Thus, the aqueous collects behind the iris and pushes it anteriorly leading to ‘iris-bombe’ formation
                • This is usually followed by a rise in intraocular pressure.
            • Total posterior synechiae
              • Occur due to plastering of total posterior surface of iris with the anterior capsule of lens
              • formed in acute plastic type of uveitis.
              • These result in deepening of anterior chamber
        • Neovascularsation of iris (rubeosis iridis)  (MCQ)
          • develops in some eyes with chronic iridocyclitis.
      • Pupillary signs (MCQ)
        • Narrow pupil.
          • It occurs in acute attack of iridocyclitis
          • occurs due to
            • irritation of sphincter pupillae by toxins
            • Iris oedema and engorged radial vessels of iris
        • Irregular pupil shape. (MCQ)
          • It results from segmental posterior synechiae formation.
          • Dilatation of pupil with atropine at this stage results in festooned (MCQ)
        • Ectropion pupillae (evertion of pupillary margin). (MCQ)
          • develop due to contraction of fibrinous exudate on the anterior surface of the iris.
        • Pupillary reaction (MCQ)
          • becomes sluggish or absent
          • occurs due to oedema and hyperaemia of iris which hamper its movements.
        • Occlusio pupillae (MCQ)
          • results when the pupil is completely occluded
          • occur due to organisation of the exudates across the entire pupillary area.
      • Changes in the lens
        • Pigment dispersal on the anterior capsule of lens
          • almost of universal occurrence in a case of anterior uveitis.
        • Exudates may be deposited on the lens
          • Occur in cases with acute plastic iridocyclitis.
        • Complicated cataract
          • develop as a complication of persistent iridocyclitis.
      • Change in the vitreous
        • Anterior vitreous may show exudates and inflammatory cells after an attack of acute iridocyclitis.
      • Complications and sequelae (mcq)
        • Complicated cataract.
        • Secondary glaucoma.
        • Early glaucoma (hypertensive uveitis) (MCQ)
          • In active phase of the disease, presence of exudates and inflammatory cells in the anterior chamber may cause clogging of trabecular meshwork
          • result in the decreased aqueous drainage
          • cause a rise in intraocular pressure (hypertensive uveitis).
        • Late glaucoma in iridocyclitis (post- inflammatory glaucoma)
          • result of pupil block not allowing the aqueous to flow from posterior to anterior chamber.
            • seclusio pupillae due to ring synechiae formation
            • occlusio pupillae due to organised exudates
        • Cyclitic membrane.
          • late complication of acute plastic type of iridocyclitis.
        • Choroiditis.
        • Retinal complications.
          • cystoid macular oedema, macular degeneration
          • exudative retinal detachment and secondary periphlebitis retinae.
        • Papillitis(inflammation of the optic disc).
        • Band-shaped keratopathy (MCQ)
          • Occurs  especially in children having Still’s disease.
        • Phthisis bulbi.

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      • Treatment of iridocyclitis (A Very High yield MCQ Zone )
        • Non-specific treatment
          • Local therapy
            • Mydriatic-cycloplegic drugs. (MCQ)
              • very useful and most effective during acute phase of iridocyclitis.
              • Commonly used drugs
                • 1 percent atropine sulfate eye ointment or drops
                • In case of atropine allergy,
                  • 2 percent homatropine
                  • 1 percent cyclopentolate eyedrops
                • a subconjunctival injection of 0.25 ml mydricain
                  • a mixture of atropine, adrenaline and procaine
                  • provides more powerful cycloplegic effect
              • cycloplegics should be continued for at least 2-3 weeks after the eye becomes quiet, otherwise relapse may occur.
              • Mode of action (MCQ frequently asked )
              • In iridocyclitis, atropine
                • gives comfort and rest to the eye by relieving spasm of iris sphincter and ciliary muscle
                • prevents the formation of synechiae and may break the already formed synechiae, reduces exudation by decreasing hyperaemia and vascular permeability
                • increases the blood supply to anterior uvea by relieving pressure on the anterior ciliary arteries. As a result more antibodies reach the target tissues and more toxins are absorbed.
            • Corticosteroids, (MCQ) administered locally
          • Systemic therapy
            • Corticosteroids
            • Non-steroidalanti-inflammatorydrugs(NSAIDS) (MCQ)
            • Immunosuppressive drugs
          • Physical measures
            • Hot fomentation
            • Dark goggles
      • Treatment of complications
        • Inflammatory glaucoma (hypertensive uveitis) (MCQ commonly asked in exam)
          • drugs to lower intraocular pressure
            • 0.5 percent timolol maleate eyedrops
            • tablet acetazolamide (250 mg thrice a day)
          • Pilocarpine and latanoprost eye drops are contraindicated in inflammatory glaucoma. (MCQ)
        • Post-inflammatory glaucoma due to ring synechiae
          • treated by laser iridotomy
          • Surgical iridectomy may be done when laser is not available.
          • Surgery should be performed in a quiet eye under high doses of corticosteroids.
        • Complicated cataract
          • requires lens extraction with guarded prognosis in spite of all precautions.
          • The presence of fresh KPs is considered a contraindication for intraocular surgery.(MCQ)
        • Retinal detachment
          • of exudative type usually settles itself if uveitis is treated aggressively.
          • A tractional detachment
            • requires vitrectomy
            • poor visual prognosis.
        • Phthisis bulbi especially when painful,
          • requires removal by enucleation operation.

Overview of uveitis Part1

Overview of uveitis Part2

Uveitis

The Causes and Symptoms of Uveitis

Diagnosis of Uveitis

Uveitis – Treatment and Symptoms