What Is Iritis Inflammation and Why Does It Occur?

The symptoms with iritis are very general, so diagnosis of the disease is often difficult. Nevertheless, it's a condition that has serious consequences.
What Is Iritis Inflammation and Why Does It Occur?

Last update: 11 July, 2021

You should be well aware of the iritis inflammation. The eyeball is a structure that specializes in the capture and transmission of luminous stimuli. The iris is responsible for regulating the amount of light absorbed by the retina. So an infection in this structure can be quite annoying. Are you interested in knowing what iritis is and why it occurs?

The iris is the pigmented ring located between the cornea and the crystalline lens. It constitutes the uvea or vascular tunica media of the eye together with the ciliary body and the choroid. It also has a series of muscles that contract and relax, adjusting the size of the central opening or pupil.

Inflammation or swelling of the iris is known as iritis or anterior uveitis. It usually develops rapidly and affects only one eye. However, in some people, it manifests in both eyes. However, early treatment is crucial to avoid complications such as glaucoma and vision loss.

Symptoms of iritis

In most cases, iritis is quite bothersome for the patient, as it can affect visual ability and hinder daily activities.

The main clinical manifestations associated with iris inflammation are as follows:

  • Ocular pain and sensitivity
  • Foreign body sensation in the eye
  • Reddened eyes
  • Increased tear production
  • Sensitivity to bright and intense lights
  • Cloudy or blurred vision
  • Headache

This condition usually manifests itself acutely and suddenly, subsiding in a period of fewer than 6 weeks. However, in some patients, it may have a chronic presentation and last for more than 3 months.

Woman rubbing her eyes
Iritis can manifest with ocular pain and intense headache, accompanied by blurred vision.

Causes and risk factors

Anterior uveitis is common in young adults between the ages of 20 and 50. However, it can also occur in children and adolescents. The origin of this condition is very varied, which makes the initial diagnosis difficult.

It’s estimated that iritis can be triggered by external factors, such as trauma and infections, as well as by endogenous alterations of the eyeball itself or as a result of systemic conditions. In addition, common causes are high-intensity blunt trauma and short penetrating injuries.

On the other hand, among the causes of iritis due to non-traumatic conditions, the following stand out:

  • Herpes Zoster virus infection
  • Toxoplasmosis
  • Tuberculosis
  • Syphilis
  • Reactive or psoriatic arthritis
  • Inflammatory bowel disease
  • Sarcoidosis
  • Reiter’s syndrome
  • Lyme disease
  • Medications, such as rifabutin and cidofovir

Recently, researchers found a relationship between the Ebola hemorrhagic virus and conditions such as uveitis and panuveitis, manifesting in more than 15% of patients.

Similarly, there are several factors that can increase the risk of suffering iritis and the possibility of suffering complications, among which are the following:

  • Tobacco and cigarette consumption
  • Hereditary alteration of the HLA-B27 gene, responsible for the stability of the immune system
  • Sexually transmitted diseases
  • Autoimmune pathologies

Complications of iritis

The negative prognosis associated with retinal inflammation is related to delayed diagnosis and late or inappropriate treatment.

Among the main complications of iritis inflammation are the following:

  • Cataract: This is an opacity of the crystalline lens that affects its refractive capacity, so the person tends to manifest progressive loss of vision. This represents the most common complication of uveitis, present in more than 30% of cases.
  • Macular edema: A thickening of the retinal macula that may occur with or without cystic lesions. In addition, it usually progresses from blurred vision to loss of vision. It’s responsible for more than 20% of complications.
  • Retinal alterations: Doctors associate this with retinal detachment or tear, the formation of problematic vessels, and vascular occlusions, which have been identified in 15% of cases.
  • Maculopathies: Related to macular necrosis, as well as a choroidal neovascular membrane (CNVM) and epiretinal membrane (ERM). These represent more than 14% of uveitis complications.
  • Other complications: Calcium deposits and irregular pupils.
A woman with cataracts
Cataracts, which are the opacity of the crystalline lens, are the most frequent complication of iritis inflammation.


The ophthalmologist makes the diagnosis of iritis inflammation by a comprehensive examination of the eyeball. The ocular symptomatology identified during the examination is vital, allowing the clinical suspicion to be developed.

This is usually confirmed by the following tests:

  • External ocular evaluation: The physician will evaluate the different structures of the eye comparatively, with the aim of identifying and ruling out any problems. Likewise, the pupillary reactivity will be studied with a small lamp, as well as the pattern of vascularization, secretion, and redness of the globe.
  • Visual acuity and visual fields test: With the help of tables or charts with figures and letters, the specialist will evaluate the focusing ability of the eyeball and its adaptive response. Likewise, by means of campimetry, the integrity or affection of the visual quadrants will be identified.
  • Fundus examination: The specialist will use an ophthalmoscope to observe the internal structures of the eye, using magnifying lenses. The doctor will evaluate the retina, macula, optic disc, and retinal vessels for abnormalities.

Treatment for iritis

The therapeutic protocol is focused on relieving ocular symptoms and controlling the disease that’s causing the inflammatory process. Likewise, the aim is to avoid the appearance of complications and the unfavorable evolution associated with vision loss.

It usually includes the following medications:

  • Mydriatic eye solutions: Drops that dilate the pupil, reducing pain and sensitivity.
  • Corticosteroids: Drops that reduce the swelling and inflammation of the iris, in addition to reducing intraocular pressure. They relieve redness, pain, and grit or foreign body sensation.
  • Oral analgesics and anti-inflammatory drugs: Drugs such as acetaminophen and ibuprofen to reduce pain and inflammation.

If the pain continues after several weeks of treatment, then the specialist may resort to the use of oral corticosteroids or infiltrates around the eyeball. As for light sensitivity, it’s advisable to use sunglasses or photochromic glasses.

Don’t hesitate to seek ophthalmologic help

In case of iritis symptoms affecting the eyeball and hindering vision, you must seek medical help immediately. In conclusion, the eye is a delicate structure that requires timely care and attention to avoid complications that may reduce or cause total loss of vision.

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