Nongranulomatous Iritis (Anterior Uveitis) Clinical Presentation

Inquire about the patient's complete medical history, including all medical conditions, surgeries, medications, and ocular history (eg, history of iritis, trauma, surgery). Perform a detailed review of systems. This is critical, as the history and the review of systems in many cases will suggest a diagnosis.

Critical review questions include, but are not limited to, asking about recent ocular trauma, back pain or stiffness, arthritis, rashes, shortness of breath, urethral discharge or dysuria, swollen lymph nodes, diarrhea, blood in stools, recent insect bites, sexually transmitted diseases (STDs),  tuberculosis (TB) exposure, and COVID-19 infection, exposure, or recent immunization.

Inquire about the onset of the symptoms. Most cases of acute anterior uveitis begin with the sudden onset of redness, pain, and photophobia.

Family history is also important. Inquire about a family history of uveitis or other symptoms in family members that might suggest associated diseases, such as a spondyloarthropathy or other HLA-B27 processes. ^[6]

A dull, aching eye pain may occur and may worsen when one touches the eye through the eyelid. Pain may be referred to the temple or periorbital region. The pain is usually abrupt in onset. Photosensitivity to light, especially sunlight, may worsen the patient’s discomfort.

Redness with no mucopurulent discharge is seen. Patients rarely have a watery discharge or tearing. Some forms of iritis, such as Fuchs heterochromic iridocyclitis, may have no symptoms other than loss of vision or glare from associated cataract.

Decreased vision may be noted.

Most cases of acute anterior uveitis are unilateral, although the same eye is not always involved in different episodes. Tubulointerstitial nephritis is a rare syndrome that is often associated with a bilateral anterior uveitis of sudden onset.

Vision

Visual acuity is usually normal or only slightly decreased, although, in severe episodes, the acuity can be very low.

Intraocular pressure

Intraocular pressure (IOP) is often lower in the eye with iritis when compared to the fellow eye. This is secondary to a decrease in aqueous production by the ciliary body. However, in some cases, the IOP may be elevated as a result of altered aqueous outflow at the level of the trabecular meshwork; this may be more common in viral anterior uveitis.

Conjunctiva

Typically, the eye has a perilimbal injection termed ciliary flush. Less commonly, generalized redness of the bulbar conjunctiva may be present. This is not found in Fuchs heterochromic iridocyclitis or the anterior uveitis associated with juvenile idiopathic arthritis.

Cornea

Keratic precipitates (KPs) may be present. These clusters of WBCs collect on the endothelium. In nongranulomatous iritis, they tend to be small and are usually located over the inferior half of the cornea. Keratic precipitates in acute anterior uveitis associated with ankylosing spondylitis are shown below.

Fine keratic precipitates in a patient with ankylosing spondylitis–associated acute anterior uveitis.

Stellate-shaped KPs, uniformly spread over the endothelium, are typical of Fuchs heterochromic iridocyclitis, as shown in the image below, and may also be seen in herpetic viral anterior uveitis.

Small stellate keratic precipitates with fine filaments in a patient with Fuchs heterochromic iridocyclitis.

Calcific band keratopathy can occur in chronic uveitides as in the uveitis associated with juvenile idiopathic arthritis. Corneal stromal edema may be present secondary to viral endotheliitis or endothelial dysfunction due to uveitic glaucoma or extensive anterior chamber inflammation. Cytomegalovirus (CMV) infection in nonimmunosuppressed patients can cause corneal edema that may even recur in corneal grafts. ^[7]

Anterior chamber

Flare, cells, and/or hypopyon may be present.

Anterior chamber flare, resulting from extra protein in the aqueous, is usually present and can be graded using the SUN Working Group Grading Scheme for Anterior Chamber Flare, as follows ^[8] :

• 0 = None
• 1+ = Faint
• 2+ = Moderate (iris and lens detail clear)
• 3+ = Marked (iris and lens detail hazy)
• 4+ = Intense (fibrin or plastic aqueous)

Cells, the hallmark of iritis, are present in the aqueous. They should be graded by severity under high-magnification slit lamp examination in a 1 X 3-mm field of light, as described by the SUN Working Group Grading Scheme for Anterior Chamber Cells, as follows:

• 0 < 1
• 0.5 = 1-5 cells
• 1+ = 6-15 cells
• 2+ = 16-25 cells
• 3+ = 26-50 cells
• 4+ = More than 50 cells

Hypopyon, if present, is highly suggestive of diseases associated with HLA-B27; with Behçet disease; or, less commonly, with an infection-associated iritis.

Acute anterior uveitis with plasmoid aqueous and hypopyon in a patient with ulcerative colitis.

Iris

Posterior synechiae may be present. Pupillary irregularity may be the result of posterior synechiae.  Synechiae may not be visible if the pupil is small. Inflammatory nodules are usually not present in nongranulomatous iritis, although Koeppe nodules can be present in Fuchs heterochromic iridocyclitis. Sector atrophy of the iris, if present, suggests herpes zoster as the etiology of the inflammation, while patchy or generalized iris atrophy suggests herpes simplex uveitis. Iris changes may also be seen in CMV anterior uveitis.

Iris atrophy in a patient with herpes simplex virus–associated anterior uveitis.

Heterochromia and loss of iris stromal detail suggest Fuchs heterochromic iridocyclitis.

Fuchs heterochromic iridocyclitis with cataract and iris heterochromia.

Lens and anterior vitreous

Lenticular precipitates may be present on the anterior lens capsule. Posterior subcapsular cataracts may be present if the patient has had repeated episodes of iritis.

Cells are commonly seen in the anterior vitreous. They represent either an iridocyclitis or a spillover of cells from the anterior chamber into the retrolental space. This may happen even in Fuchs iridocyclitis.

Occasionally, patients with HLA-B27 disease have an intense vitritis, papillitis, and cystoid macular edema.

Posterior segment

Carefully examine the posterior segment through a dilated pupil for evidence of optic nerve edema, for vasculitis, and for focal retinal and/or choroidal lesions. All patients with acute anterior uveitis must undergo dilated fundus examination to ascertain that the diagnosis is confined to the anterior segment. A patient with a granulomatous-appearing iritis is likely to have a more extensive uveitis.

It is important to ascertain whether the uveitis is unilateral or bilateral, symptomatic (pain and photophobia), and acute (lasting less than 3 months) or chronic.

Unilateral, sudden onset, acute

Causes of acute anterior uveitis may include the following:

• Idiopathic
• Diseases associated with HLA-B27 (eg,  ankylosing spondylitis,  reactive arthritis,  inflammatory bowel disease,  psoriasis) may manifest as unilateral acute anterior uveitis; they have a high tendency to recur at some later time in the same eye or contralateral eye; 50% of HLA-B27–positive patients with acute anterior uveitis will develop an associated seronegative spondyloarthropathy; 25% of patients with HLA-B27–associated systemic illness will develop acute anterior uveitis ^[1]
• Behçet's disease
• Sarcoidosis
• Trauma
• Infections (herpes zoster, herpes simplex, CMV, syphilis, postoperative or metastatic endophthalmitis)

Immune dysregulation presenting with uveitis in a child with COVID-19 related multi-inflammatory syndrome has been described. ^[9]  In addition, there are numerous anecdotal reports of both conjunctivitis and anterior uveitis associated with COVID-19 infection.

Unilateral, chronic

Infectious causes may include the following:

• Herpes zoster, herpes simplex, acute retinal necrosis, CMV
• Syphilis
• Fuchs heterochromic iridocyclitis (which may be due to rubella, at least in some cases)

The following are other potential causes:

• Sarcoidosis
• Chronic postoperative endophthalmitis

Bilateral

Causes of bilateral disease may include the following ^[10] :

• Sarcoidosis
• Lyme disease
• Fuchs heterochromic iridocyclitis (rare cause)
• Juvenile idiopathic arthritis ^[11]
• Acute retinal necrosis
• Tuberculosis
• Tubulointerstitial nephritis and uveitis syndrome (a small group of patients with interstitial nephritis has tubulointerstitial nephritis and uveitis)