Scleritis is a painful inflammatory condition of the sclera, the tough white outer wall of the eye, and it poses a real threat to vision if left untreated. Unlike the more common and milder episcleritis, which affects only the thin tissue overlying the sclera, scleritis reaches deep into the eye wall itself and can damage surrounding structures. It is uncommon, but when it strikes, the pain tends to be severe enough that people seek help quickly. In many cases the eye inflammation turns out to be a signal of a broader autoimmune disease happening elsewhere in the body, which makes scleritis a condition that eye doctors and rheumatologists often manage together.
What the Sclera Is and Why It Is Vulnerable
The sclera is the dense, collagen-rich shell that gives the eyeball its shape and protects the delicate tissues inside. It is mostly made of tightly woven collagen fibers, with relatively few cells and very little blood supply of its own. Nutrients reach it indirectly, from a thin network of small vessels in the overlying episclera and from the choroid underneath.1PubMed. Scleral structure, organisation and disease The sclera also lacks lymphatic vessels under normal conditions, a feature that is actively maintained by a balance of pro- and anti-growth signals from scleral cells.2PubMed. The lymphangiogenic and hemangiogenic privilege of the human sclera
That sparse blood supply is a double-edged sword. On one hand, it keeps the sclera relatively quiet immunologically. On the other hand, the slow, oscillating blood flow in the episcleral vessels makes the tissue prone to vasculitis, where the immune system attacks blood-vessel walls. When that happens, inflammatory cells flood in, enzymes chew through the collagen framework, and the sclera can thin dramatically or even perforate.1PubMed. Scleral structure, organisation and disease The breakdown of collagen fibrils by both resident scleral cells and invading immune cells appears to be a central feature of the disease process.3PubMed. Therapy insight: scleritis and its relationship to systemic autoimmune disease
How Scleritis Feels
The hallmark symptom is deep, boring eye pain that can radiate to the forehead, cheek, or jaw on the same side. Many people describe it as a constant ache that worsens at night and can wake them from sleep. The pain often intensifies with eye movement. This is different from the gritty irritation of dry eye or the mild tenderness of episcleritis; scleritis pain tends to be severe enough to interfere with daily life.4PubMed Central. Scleritis: Differentiating infectious from non-infectious entities
Alongside the pain, the white of the eye turns a deep red or violet hue. In anterior scleritis, which affects the front of the eye, you can see this redness clearly. Sometimes a raised, tender nodule forms on the sclera. In more aggressive forms, the scleral tissue thins and takes on a bluish tint because the underlying choroid shows through. Vision may blur if the inflammation spills over into the cornea or the uvea (the pigmented layer inside the eye).5PubMed. Scleritis
Posterior scleritis, which involves the back of the eye, is trickier to recognize. The external eye can look relatively normal. Instead, people notice blurred or distorted vision, sometimes with pain behind the eye. Fluid can collect under the retina, causing a detachment, or the optic nerve head can swell. Because these signs overlap with other conditions, posterior scleritis is frequently misdiagnosed at first.
Autoimmune Causes
In the majority of non-infectious cases, scleritis is driven by the immune system attacking the body’s own tissues. Rheumatoid arthritis is the single most commonly associated systemic disease. Roughly one in fifty people with rheumatoid arthritis develops scleritis at some point, and the condition accounts for somewhere between 8 and 15 percent of all scleritis cases.6PubMed Central. Rheumatoid Arthritis Associated Episcleritis and Scleritis: An Update on Treatment Perspectives These patients tend to develop more severe forms, including necrotizing scleritis, and may need aggressive treatment early on.
ANCA-associated vasculitis, a group of conditions in which immune proteins target certain white blood cells and inflame small blood vessels throughout the body, is the other major autoimmune culprit that rheumatologists watch for closely.7PubMed. Noninfectious Autoimmune Scleritis: Recognition, Systemic Associations, and Therapy Granulomatosis with polyangiitis (formerly called Wegener’s granulomatosis) is a well-known example. Other linked conditions include lupus, inflammatory bowel disease, relapsing polychondritis, and spondyloarthritis, though each of these is individually less common as a cause of scleritis.
Sometimes scleritis is the first sign that an autoimmune disease is brewing. A person may walk into the ophthalmologist’s office with a painfully red eye and leave with blood-test orders that ultimately reveal rheumatoid arthritis or vasculitis they did not know they had. This is one reason a thorough systemic workup matters even when the eye symptoms seem to be the only problem.
Infectious and Drug-Related Triggers
A smaller but important fraction of scleritis cases are caused by infections rather than autoimmunity. The most common scenario involves previous eye surgery, particularly pterygium removal, cataract extraction, and procedures that use radiation or antimetabolite drugs on the eye surface. These surgeries can thin the sclera and compromise its blood supply, creating an environment where bacteria or fungi can take hold.8Open Forum Infectious Diseases. Infectious Scleritis: What the ID Clinician Should Know In one tertiary-center study, prior surgery was the leading risk factor, present in well over half the cases of bacterial and fungal scleritis.9PubMed Central. Risk Factors and Clinical Outcomes of Bacterial and Fungal Scleritis at a Tertiary Eye Care Hospital Trauma with organic material like soil or plant matter is another well-recognized route, particularly for fungal and Nocardia infections.8Open Forum Infectious Diseases. Infectious Scleritis: What the ID Clinician Should Know
Distinguishing infectious scleritis from autoimmune scleritis matters enormously because the treatments are almost opposite. Autoimmune scleritis calls for suppressing the immune system; infectious scleritis requires ramping the immune response up while targeting the microbe. Giving steroids to someone with an unrecognized infection in the sclera can make things much worse. Diabetes and prior use of topical or systemic steroids are additional risk factors for the infectious form.9PubMed Central. Risk Factors and Clinical Outcomes of Bacterial and Fungal Scleritis at a Tertiary Eye Care Hospital
Medications themselves can occasionally trigger scleral or ocular inflammation. Bisphosphonates, widely prescribed for osteoporosis, are a recognized cause. Nitrogen-containing bisphosphonates provoke an acute-phase reaction in a substantial proportion of patients, typically within the first day or two of an intravenous infusion. The resulting surge in inflammatory signaling molecules can produce uveitis, scleritis, or orbital inflammation. The risk is highest with the first infusion and drops with subsequent doses.10Clinical Optometry. Drug-Induced Uveitis: Patterns, Pathogenesis and Clinical Implications
How Scleritis Is Diagnosed
Most anterior scleritis is diagnosed clinically: a doctor sees the characteristic deep redness, feels the tenderness, and hears the patient describe severe boring pain. Distinguishing scleritis from episcleritis is one of the first challenges. Episcleritis affects only the superficial episcleral layer, causes mild discomfort rather than severe pain, and usually resolves on its own. A classic bedside test involves placing a drop of phenylephrine on the eye, which blanches the superficial episcleral vessels but not the deeper scleral vessels involved in scleritis.
Posterior scleritis requires imaging. B-scan ultrasonography is a workhorse tool here. It can reveal thickening of the scleral-choroidal complex and fluid collecting behind the eye in Tenon’s capsule, producing the so-called T-sign, a characteristic appearance on the scan that is highly suggestive of the diagnosis.11PubMed Central. The clinical features of posterior scleritis with serous retinal detachment: a retrospective clinical analysis Comparing the thickness of the back of the affected eye to the unaffected eye can be helpful: one study found that a scleral-choroidal thickness above 1.7 mm had both high sensitivity and high specificity for the diagnosis.12PubMed Central. B-Scan Ultrasonography Findings in Unilateral Posterior Scleritis
Optical coherence tomography, which generates cross-sectional images of eye tissues with very fine detail, is increasingly used alongside ultrasound. Specialized versions of this technology can visualize changes deep in the choroid beneath the inflamed sclera, showing marked thickening during active disease and thinning as inflammation responds to treatment.13PubMed. Choroidal observations in posterior scleritis using high-penetration optical coherence tomography
The Systemic Workup
Because scleritis so often signals an underlying systemic disease, blood tests are a standard part of the evaluation. A typical workup includes markers for rheumatoid arthritis, ANCA antibodies, antinuclear antibodies, syphilis serology, and tuberculosis screening, among others. In one large series, ANCA testing was performed in nearly all patients. When the ANCA result was non-specific (positive on the screening test but without a particular antibody identified), the positive predictive value for an associated systemic vasculitis was only about 29 percent. But when more targeted testing identified specific antibodies like anti-PR3, the predictive value jumped to 86 percent, making it a much more useful signal.14PubMed Central. Scleritis and associated systemic diseases: contribution of systemic examination, follow-up, and additional investigations
If initial labs come back clean but the clinical suspicion remains high, referral to a rheumatologist or internist for a more thorough physical examination makes sense. In that same series, repeating laboratory tests during follow-up did not produce additional diagnoses beyond what the initial workup found, which suggests that the first round of testing is the one that counts most.14PubMed Central. Scleritis and associated systemic diseases: contribution of systemic examination, follow-up, and additional investigations
First-Line Treatment
For mild to moderate non-necrotizing anterior scleritis, oral anti-inflammatory drugs like ibuprofen, naproxen, or indomethacin are usually tried first. In an analysis of treatment outcomes across scleritis subtypes, initial failure rates for anti-inflammatories were low in both diffuse and nodular scleritis, around 7 to 9 percent.15PubMed. An analysis of therapeutic decision for scleritis That means most patients with these milder forms respond to medications you can buy at a pharmacy, though the doses used tend to be higher than what people take for a headache.
When anti-inflammatories are not enough, oral corticosteroids like prednisone come next. They are powerful at shutting down inflammation, but they carry well-known side effects with prolonged use, including elevated eye pressure, cataracts, bone thinning, and weight gain. For that reason, doctors try to keep steroid courses as short as possible and taper the dose once the inflammation is controlled.
When Standard Treatments Fall Short
Necrotizing scleritis, posterior scleritis, and any case linked to a systemic vasculitis typically require stronger immune-suppressing medications. Antimetabolites like methotrexate and mycophenolate, T-cell inhibitors like cyclosporine, and biologic therapies are all options for refractory or severe disease.16PubMed Central. Pharmacotherapy of scleritis: current paradigms and future directions In clinical practice, the choice often depends on what underlying systemic disease is present and what other medications the patient is already taking for it.
Biologic therapies targeting specific immune pathways have gained ground in recent years. Rituximab, which depletes a particular type of immune cell, was tested in a phase I/II trial for patients whose scleritis had resisted conventional immunosuppressives. It controlled the disease in nine out of twelve enrolled patients by six months, though most needed a repeat infusion to maintain that control.17PubMed. Rituximab therapy for refractory scleritis: results of a phase I/II dose-ranging, randomized, clinical trial That finding is promising but also illustrates a common theme in scleritis management: the disease tends to relapse, and long-term treatment plans have to account for that.
When Surgery Becomes Necessary
Surgery is rarely needed and is essentially reserved for emergencies. The most common scenario is necrotizing scleritis that has thinned the scleral wall to the point of perforation or near-perforation. In these cases, a patch graft using donor sclera, preserved tissue, or even synthetic material is placed over the weakened area to prevent the eye from collapsing. Various graft materials have been used, including fascia lata, periosteum, and homologous sclera.18PubMed. Scleral patch graft in the management of necrotizing scleritis A reinforcement suturing technique, using overlapping compressive sutures over the patch, has been described for cases with bulging uveal tissue pushing through the thinned sclera.19PubMed. Scleral Patch Graft With a Suture Reinforcement Technique in Surgical Management of Necrotizing Scleritis With Ectasia
A critical point that surgeons emphasize: the patch graft is a structural rescue, not a cure. If the underlying immune dysfunction that caused the tissue destruction is not also treated with medications, the graft itself will be attacked and the patient risks losing the eye.18PubMed. Scleral patch graft in the management of necrotizing scleritis
Complications and What Determines Visual Outcome
Scleritis can damage the eye in several ways beyond the scleral wall itself. The most frequent complication in one Japanese cohort was elevated eye pressure, seen in about 41 percent of cases, followed by inflammatory cells spilling into the front chamber of the eye in roughly 38 percent.20PubMed. Clinical characteristics and ocular complications of patients with scleritis in Japanese Over time, chronic inflammation can lead to cataracts, glaucoma, corneal thinning, and optic nerve damage.
Not all subtypes carry the same risk. A large study identified several factors that independently predicted vision loss: necrotizing scleritis carried the highest risk, followed by posterior scleritis, intense scleral inflammation, associated anterior uveitis, elevated eye pressure, and an underlying infectious cause.21Ophthalmology. Severity of Scleritis and Episcleritis In the Japanese cohort, about a third of patients with necrotizing or posterior scleritis experienced a decrease in vision, with secondary glaucoma and optic nerve inflammation being the leading causes.20PubMed. Clinical characteristics and ocular complications of patients with scleritis in Japanese
The good news is that diffuse and nodular anterior scleritis, the most common forms, generally respond well to treatment and carry a much lower risk of lasting visual damage. Patients who are treated promptly tend to see meaningful improvement in both symptoms and visual acuity, and studies tracking quality of life show substantial gains after treatment that go beyond just the eye itself, improving overall psychosocial well-being.22PubMed Central. Vision-related quality of life and psychosocial well-being of patients with episcleritis and scleritis: a neglected essence?
Scleritis in Children
Scleritis is rare in adults and even rarer in children, which means it often catches clinicians off guard. The pattern in children looks somewhat different from the adult version. Posterior scleritis without an identifiable cause is the most common subtype seen in childhood, and autoimmune associations are less frequent than in adults.23PubMed. Pediatric Scleritis: An Update In one series of thirteen children with posterior scleritis, none had an underlying connective tissue disease, and standard autoimmune blood markers were essentially unrevealing.24Ophthalmology. Posterior Scleritis in Children: Clinical Features, Systemic Associations, and Treatment Outcomes
Treatment tends to escalate faster in children. In that same series, only one child responded to anti-inflammatory drugs alone. Nearly all required oral corticosteroids, and the majority relapsed when the steroid dose was reduced, ultimately needing a secondary immunosuppressive agent.24Ophthalmology. Posterior Scleritis in Children: Clinical Features, Systemic Associations, and Treatment Outcomes Case reports of anterior scleritis in children are even scarcer, but they echo the same theme: the disease can be stubborn, often resists first-line therapy, and requires a careful diagnostic search for hidden systemic causes despite the lower yield of that workup compared to adults.25PubMed Central. Idiopathic Anterior Scleritis in Pediatric Patients: A Report of Two Cases
The rarity of pediatric scleritis means there are no large randomized trials guiding treatment in this age group. Clinicians largely extrapolate from adult data and published case series, tailoring therapy to the child’s subtype, severity, and tolerance of medications. A multidisciplinary approach with pediatric rheumatology involvement is considered best practice, even when no systemic disease has been found, because autoimmune conditions can declare themselves years after the eye inflammation first appears.23PubMed. Pediatric Scleritis: An Update
Living With Scleritis and Managing Recurrences
One of the more frustrating aspects of scleritis for patients is its tendency to come back. Even after successful treatment, many people experience flares, sometimes triggered by tapering their medication too quickly, sometimes without an obvious reason. The relapse pattern is especially pronounced in people with underlying autoimmune disease, where the eye inflammation may track with disease activity elsewhere in the body.
The psychosocial toll can be substantial. Chronic eye pain, unpredictable flares, and worry about losing vision take a measurable toll on quality of life. Research comparing patients with scleritis to those with the milder condition episcleritis found that scleritis had a significantly greater negative impact on vision-related quality of life and psychological well-being, but also that successful treatment brought significant improvement.22PubMed Central. Vision-related quality of life and psychosocial well-being of patients with episcleritis and scleritis: a neglected essence? That finding reinforces why getting adequate control early, rather than tolerating smoldering inflammation, matters beyond just protecting the tissue.
Patients on long-term immunosuppressives need monitoring for medication side effects, including regular blood counts, liver-function tests, and screening for infection. Eye-pressure checks and cataract screening are important for anyone who has been on corticosteroids. Many ophthalmologists settle into a routine of visits every few months during remission, with the understanding that any return of deep eye pain warrants an urgent appointment rather than waiting for the next scheduled one.