Scleritis

Because Treponema pallidum is sensitive to penicillin G, this antibiotic is the drug of choice for treatment of syphilis and syphilitic eye disease (see Table 11-1). Syphilitic eye disease can include interstitial keratitis (stromal inflammation and vascularization), episcleritis, scleritis, nongranulomatous or granulomatous iritis, iris papules (collections of dilated capillaries in the iris), chorioretinitis, papillitis, retinal vasculitis, and exudative retinal detachment. Probenecid can be added to procaine penicillin to decrease excretion of the penicillin by the kidneys, thus causing an increase in penicillin plasma levels. Penicillins are not used for the treatment of minor ocular infections such as blepharitis and conjimctivitis... 

Several randomized double-blind trials provided evidence that oral acyclovir 800 mg, five times daily, is the most effective dosage for treating HZO. Studies also stressed the importance of initiating treatment within the first 72 hours to prevent severe complications of HZO (i.e., keratitis, uveitis, secondary glaucoma, scleritis, optic neuritis, and acute retinal necrosis [ARN]).When there is ophthalmic involvement, it is recommended to treat even if the rash has been present for more than 72 hours. In addition, there is evidence that 7 days of treatment may be adequate. Studies have been shown that oral acyclovir may lessen the incidence and duration of postherpetic neuralgia associated with HZO, as shown in Table 11-10. 

Anterior uveitis Posterior uveitis Sympathetic ophthalmia Sclera Scleritis Episcleritis Retina... 

Clinical evaluation of patients with conjunctivitis, episcleritis, and scleritis indicates that fluorometholone acetate improves clinical signs and symptoms of inflammation significantly more than fluorometholone alcohol. Furthermore, when fluorometholone acetate 0.1% was compared with prednisolone acetate 1.0% in patients... 

Tuberculosis Unilateral Sectoral, inferior Anterior or mild stromal Scleritis... 

Additional findings in EKC can include pseudomembrane formation (Figure 26-46) and corneal epithelial sloughing. Symblepharon, scleritis, and anterior uveitis rarely develop. Nasolacrimal system obstruction due to inflammation or adhesion of opposing surfaces, as occurs in symblepharon formation, also is a rare complication. 

Ocular involvement can develop as soon as several days, to as long as years, after vesicle formation. Ocular involvement may inclnde lid edema, follicnlar conjunctivitis, corneal changes, anterior nveitis, glancoma, episcleritis, scleritis, Horner s syndrome, extraocnlar muscle palsy, chorioretinitis, optic nenritis, and scarring of the lids and lacrimal canalicnlar system. It is possible, but rare, to have ocular complications, snch as nveitis and disciform keratitis, withont any skin lesions. 

Episcleritis is clinically classified as either simple or nodular. Simple episcleritis is usually the milder form, being limited to a sector of the eye in approximately two-thirds of cases, but can affect the entire episclera in approximately one-third of cases. Nodnlar episcleritis is nsually more serious and involves the presence of a definitive nodule and mild to moderate discomfort. Approximately 20% to 25% of cases present as nodular. Only 2% to 5% of episcleritis progresses to scleritis. Simple episcleritis usually lasts 1 to 3 weeks, whereas nodular episcleritis has a more variable course, in some cases lasting up to 2 months. Both forms periodically recnr but become less frequent with time until the disease no longer remits. Either form may recur as the other. 

Adapted with permission from Castells DD. Anterior scleritis three case reports and a review of the literature. Optometry 2004 75 437... 

Unlike the more commonly encoimtered episcleritis, inflammation of the sclera is relatively rare, painfiil, and capable of extensive and permanent tissue and visual destruction. Scleritis is characterized by an immime-mediated vasculitis and inflammatory cell infiltration of the sclera and episclera. Scleritis usually occurs in the fiaurth to sixth decades of life but can be seen at any age. Peak incidence fi>r men is in the fiaurth decade, whereas there are two peaks for women the third and sixth decades. Diffuse scleritis shows a 1 1 distribution, whereas the other forms, particularly necrotizing and posterior scleritis, show a female predilection. Scleritis presents bilaterally about 50% of the time, and unilateral presentations usually... 

The pathophysiology of scleritis is complex and not fully understood.The main dysfunction is thought to be the deposition of immime complexes in the vasculature of the sclera and episclera, creating a vasculitis. This leads to edema and inflammatory cell infiltration of the sclera and episclera, which in turn cause disorganization and destruction of the collagen lamellae. However, not all presentations of scleritis demonstrate the same pathology. 

In diffuse anterior scleritis (Figure 28-4), the pain is often less severe. This form of scleritis is the mildest and most common type, and it manifests as an area of sectorial or diffuse dilation of the deep episcleral vascular plexus with overlying and adjacent episcleritis that can affect the whole eye. There can be mild anomalous changes in the blood vessels that may persist even after successful treatment, which is associated with a 9% incidence of vision loss. 

Nodular scleritis consists of one or more focal nonmovable nodules of inflamed scleral tissue (Figure 28-5), usually in the interpalpebral region. These nodules are frequently tender to palpation, and nodular scleritis is more likely to cause severe or radiating pain than diffuse scleritis. 

Figure 28-4 Diffuse scleritis with deep vessel injection and associated episcleritis.

Figure 28-5 Focal scleral and episcleral inflammation seen in nodular scleritis.

Topical anesthetic installation followed by applied pressure with a cotton swab to the inflamed site can be useful in diagnosis. If this elicits a pain response, scleritis or episcleritis should be suspected, whereas the absence of pain suggests conjunctivitis or uveitis. If 10% phenylephrine or epinephrine 1 1,000 blanches all episcleral vessels, then a scleritis is not present however, these drugs do not constrict the deep episcleral vascular plexus that is dilated in scleritis. 

Lesion color and examination lighting can play a crucial role in scleritis evaluation. For example, red-free light can be used to enhance blood vessels and may allow the clinician to observe areas of vascular closure (Figure 28-6) within a scleritis lesion. These areas represent vascular occlusion and destruction from progressive infiltrative inflammation. Except in scleromalacia perforans, anterior scleritis creates a characteristic bluish red or purplish (violaceous) color in contrast to the salmon red or bright red injection observed in episcleritis. This violaceous... 

Figure 28-6 Scleritis with areas of vascular closure...

Traditional examination alone may not always be adequate to diagnose or manage scleritis, to identify areas of early vascular closure (see Figure 28-6), to differentiate benign nondestructive scleritis from necrosis, or to adequately monitor the success of treatment. Although not readily available, high-frequency ultrasound biomicroscopy... 

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