Iritis
Iritis is a term describing inflammation of the eye structures surrounding iris. Iritis is used interchangeably with another condition called anterior uveitis. Uveitis is more involved inflammation of the eye that can affect the optic nerve, sclera, and retina. In a way, this terminology is important to the ophthalmologists to describe the segments of the eye that are inflamed.
In this article:
- Iritis Treatment
- Medical treatment of Iritis
- Drugs to treat iritis
- Iritis treatment at home
- Iritis Complications
- References
Iritis Treatment
Treatment aims at eliminating inflammation and pain with steroids and topical cycloplegics. The main goal is to prevent complications and blindness. Any additional therapies depend on associated processes. For example, anti-viral medications are necessary in herpetic uveitis, while bactrim can be used in toxoplasmic chorioretinitis.
Antimetabolite, biologics, and other immunosuppressive medications (e.g., methotrexate, azathioprine, mycophenolate, cyclosporine, adalimumab, and infliximab) are often necessary for chronic, non-infectious cases, especially in cases associated with systemic inflammatory diseases. However, these agents should only be prescribed by doctor specifically trained in their use and attuned to their side effect profile.
Medical treatment of Iritis
For anterior uveitis therapy consists of topical corticosteroids and cycloplegics. Steroids should be tapered according to clinical response to minimize rebound inflammation.
People should return for a scheduled follow-up after 1 week of treatment with corticosteroids. During this visit and each subsequent visit, the number of anterior chamber cells/high-power field (HPF) should be half of what it was at the initial examination. If the number of cells is not decreasing, then the primary eye care practitioner should suspect one of two things: the patient is either not using the drops correctly, or an infection should be suspected, such as herpes.
Cycloplegics, typically atropine or cyclogyl, are used to minimize pain by reducing spasm of the ciliary body and prevent and/or lyse posterior synechiae (adhesions of the iris to the lens capsule). These medications are typically applied twice daily until inflammation has resolved or has significantly decreased before cessation.
Drugs to treat iritis
Initial treatment of anterior uveitis involves topical corticosteroids. The most common topical corticosteroid prescribed for the treatment of anterior uveitis is prednisolone acetate 1%, followed by dexamethasone 0.1% and prednisolone sodium phosphate 1%. Ophthalmologist needs to monitor a person for resolution of inflammation and measure intraocular pressure if prolonged topical steroid used.
Viral iritis treatment: to reduce an inflammation and heal tissues of the eye doctor prescribes a combination regimen: Oral acyclovir, topical corticosteroids, and cycloplegics/mydriatic agents. In severe and recurrent disease, maintenance therapy of oral acyclovir is useful to prevent a relapse. Alternatively, valacyclovir may also be used.
Systemic antiviral therapy combined with low-dose corticosteroid drops may have to be used for several years, to prevent relapses. For people with raised intraocular pressure antiglaucoma medications are given topically.
Severe elevation of IOP may require oral carbonic anhydrase inhibitors and filtration surgery.
Resistance of herpes simplex virus (HSV) to acyclovir and cytomegalovirus (CMV) to ganciclovir is a recently reported phenomenon. HSV resistance to acyclovir occurs due to specific mutations in the viral thymidine kinase, mutations in the viral DNA polymerase gene, HSV having a deficient thymidine kinase protein or the natural hypervariability of HSV thymidine kinase gene.
Acyclovir resistant HSV strains also show some amount of cross-resistance to ganciclovir which has implications in management of these patients. Use of cidofovir and foscarnet is recommended to treat acyclovir resistant HSV anterior uveitis.
Brimonidine should be used with caution to treat high IOP in patients of viral anterior uveitis. Brimonidine may cause granulomatous anterior uveitis which may mimic recurrence of viral anterior uveitis. This side-effect may present with or without symptoms, usually many months after initiation of treatment. It may occur only in unilaterally and is fully reversible once brimonidine is withdrawn.
Iritis treatment at home
Self-treatment of iritis is not recommended due to potential of vision loss. At home you should strictly follow recommended by a specialist treatment. It is also important to shake the steroid suspension as failure to do so may result in a subtherapuetic response.
Usually, hourly instillation of topical corticosteroids with weekly follow-up visits until there are five or fewer cells/HPF. Once five or fewer cells/HPF are present in the anterior chamber, the frequency of drop instillation should be reduced to every 2 hours.
Follow-up care for iritis
Uveitis is a condition that can present in emergency departments or primary care settings. It is important to recognize symptoms and make an accurate diagnosis. It is vital for primary care providers to refer the patient to an ophthalmologist if uveitis is suspected.
Treatment for uveitis should be handled by an interprofessional team approach that includes:
- ophthalmologists
- retina and uveitis specialists
- specialty-trained nurses
- rheumatologist or allergist (for systemic disease)
- pharmacists
It is very important to have continuous care by an ophthalmologist, as in many cases systemic disease can relapse causing vision loss.
Iritis Complications
Prolonged or undertreated intraocular inflammation can lead to pathological changes in the eye resulting in permanent vision loss. These complications include:
- cataracts
- iris adhesions,
- epiretinal membrane (ERM),
- cystoid macular edema (CME)
- band keratopathy,
- hypotony,
- glaucoma,
- optic nerve edema