OVERVIEW
Rheumatoid arthritis (RA) is a common autoimmune disease with multi-system inflammation characterized by chronic inflammatory lesions in joint tissues. It can also damage extra-articular tissues such as the eyes, skin, lungs, heart and peripheral nerves.
Causes
The cause of the disease is unknown and may be related to a variety of factors that induce an autoimmune response in the body. The following 3 related areas are currently considered most promising:
1. Host genetic factors
2. Abnormalities in immunoregulation and autoimmunity
3. triggered or persistent microbial infections
There are also dampness, cold, fatigue, malnutrition, trauma, and psychiatric factors, especially dampness and cold as the main triggers of the disease.
Symptoms
1. Scleritis
RA is the most common systemic disease causing scleritis. The incidence of RA in patients with scleritis is 10% to 33%. The incidence of scleritis in patients with RA ranges from 0.15% to 6.3%. RA scleritis is more common bilaterally in patients over 60 years old, and is more common in females than males. the most common type of RA scleritis is diffuse anterior scleritis. Patients have symptoms such as eye redness, eye pain, photophobia, tearing, conjunctival sac discharge and vision loss. It is mainly characterized by a diffuse anterior scleral inflammatory infiltrate, with few comorbidities and a relatively better prognosis than other types of scleritis. The sclera in the lesion area is suddenly and diffusely congested, and the bulbar conjunctiva is edematous; in severe cases, epinephrine drops are needed to see the sclera clearly.
2. Scleral episcleritis
RA scleral episcleritis is more common in women than in men, and it is more common in elderly patients around 60 years old. It is unilateral or bilateral, and the type is simple or nodular. Simple scleral episcleritis has an acute onset, short course, and periodic recurrence. In the acute phase, the affected eye has discomfort such as photophobia, tearing and burning pain. There is limited congestion and edema of the superficial sclera at the site of the lesion, and the conjunctiva can be moved. Nodular scleral episcleritis tends to be acute in onset, short in duration, and characterized by limited nodular elevation of the scleral surface. The nodules are mostly solitary, dark red in color, and 2 to 3 mm in diameter. The nodule and the surrounding bulbar conjunctiva are congested and edematous, and can be pushed. 2/3 patients can have multiple recurrences in different parts of the body, and the condition can be gradually relieved and completely subside, usually not affecting vision, and individual patients can develop scleritis.
Examination
The first step is to determine whether the patient has rheumatoid arthritis.
1. Rheumatoid factor (RF)
70% to 90% of patients with RA are RF positive. RF positivity is also seen in healthy individuals with secondary immune responses. The RF titer often correlates with the severity of the RA lesion; RA scleritis is usually RF positive, and some patients have high titers.
2. Blood count
There is usually normocytic normochromic anemia, occasionally eosinophils and thrombocytosis. Treatment of proliferative synovitis may reduce or eliminate hematologic abnormalities.
3. Acute phase reactants
Almost all patients have increased sedimentation rate (ESR) and increased C-reactive protein (CRP), both of which correlate positively with RA lesion activity. patients with RA scleritis have higher ESR values than RA patients without scleritis. After treatment, a decrease in ESR and CRP indicates improvement and slowing or reversal of joint destruction.
4. Synovial fluid analysis
RA synovial fluid is turbid, with low viscosity, forming a small amount of mucin clot, mildly decreased glucose concentration, increased protein content, and a markedly increased leukocyte count of (2,000-75,000) × 106/L, and more than 50% are neutrophils. Hemolytic complement (C3 and C4) within the synovial fluid was less than 30% of normal serum complement, suggesting that classical complement channels were activated by locally produced immune complexes. Histologic examination of synovial fluid is also helpful in the diagnosis of RA.
5. Circulating immune complexes (CIC)
CIC is not specific for RA, but can be used as a diagnostic and prognostic indicator of RA. In early arthritis, CIC can appear months before the diagnosis of RA. 70% of RF-negative RA patients can find CIC, which can help to distinguish RF-negative RA patients from other joint lesions. CIC levels correlate with the degree of activity of the lesion, but are not as sensitive as ESR, CRP, or IgG-type RF. vasculitides in RA patients have higher CIC levels.
6. Antinuclear antibodies (ANA)
Detection of serum antibodies against antigenic components of the nucleus and cytoplasm is useful in the diagnosis of patients with RA. The best means of routinely checking for ANA is immunofluorescence assay by Hep-2 cells, with results reported as positive or negative, including titers and graphs.
7. Complement
Serum complement is decreased in RA patients presenting with CIC and RF positivity. Low complement levels are commonly seen in patients with vasculitis in RA.
8. X-ray
Early manifestations of periarticular soft tissue swelling and joint cavity oozing, further development of the lesion is paraprosthetic osteoporosis, loss of articular cartilage, bone invasion and joint bone ankylosis deformity.
9. Ultrasound and CT scan
Scleral wall thickness is helpful in the diagnosis of RA posterior scleritis.
Diagnosis
Specific diagnostic tests are lacking. The diagnosis is mainly based on the clinical manifestations of sclerochoroiditis in RA, which is helped by the presence of RF positivity, increased ESR and CRP, characteristic histologic changes of synovitis, synovial and subcutaneous nodules, as well as periarticular osteoporosis and x-ray manifestations of joint erosions and joint invasive changes.
Treatment
1.Aim of treatment
RA scleritis has a long course, and the objectives of disease control are: (1) to relieve pain; (2) to reduce inflammation; (3) to minimize the side effects of medication; (4) to protect muscle strength, joints, and visual function; and (5) to return to a normal lifestyle as soon as possible.
2.Drug treatment
(1) Treatment of RA scleral epiphora Although the condition of RA simple scleral epiphora may deteriorate and may affect the patient’s appearance for a short period of time, it can be treated without medication. Because scleral epiphora is a benign relapsing disease, it is self-limiting and can resolve on its own within a few days without sequelae. Mild therapies such as cold compresses, cold artificial tears, and vasoconstrictor drops can be effective in simple scleral episcleritis.
If medication is used, nonsteroidal anti-inflammatory drugs (NSAIDs) are preferred. As a basic treatment, anti-inflammatory is very important, NSAID can be applied topically or systemically, and can be effective in some cases of simple scleral episcleritis. In clinical practice, it is sometimes necessary to screen among these drugs in order to maximize the therapeutic effect and minimize side effects in each patient.
(2) Treatment of RA scleritis In patients with RA who have diffuse or nodular anterior scleritis, an oral NSAID can be administered and topical glucocorticoid eye drops can be applied. A choice of multiple NSAIDs is usually required. After selecting an NSAID, the treatment period should be at least 1 year, after which the drug should be gradually reduced and discontinued. If the drug is ineffective or the scleritis recurs after stopping the glucocorticoid eye drops, switch to another NSAID and apply glucocorticoid eye drops at the same time, and observe whether the disease recurs after the glucocorticoid dose is reduced. The above steps can be repeated several times until the most appropriate NSAID drug is identified or whether it is used in conjunction with other drugs. Combination medications are effective treatment options, and short-term applications of prednisone are generally considered. Most patients with RA nodular scleritis are effectively treated with the above treatment options, but a small number of patients still need to be treated with small doses of immunosuppressive drugs.
3. Surgery
Patients with scleritis rarely need surgery, unless necrotizing anterior scleritis has a tendency to perforate or has already been perforated, scleral reinforcement can be considered. Since rheumatoid necrotizing anterior scleritis is caused by an autoimmune abnormality, it can also cause destruction of any grafts (sclera, periosteum, and fascia) that reinforce the sclera.
Prognosis
The prognosis for RA scleritis is poor; 36% to 45% of patients with RA scleritis die within 3 years of the onset of scleritis.
Prevention.
The presence of necrotizing anterior scleritis in patients with RA usually predicts a potentially lethal systemic vasculitis. When this occurs, high vigilance should be exercised, and early screening for ocular and systemic disease should be done. Early detection and early effective treatment measures will not only improve the ocular condition well, but also improve the poor prognosis of the patient’s systemic condition.