Posterior scleritis in pediatric age group: A case report and review of literature.

Posterior scleritis is rare in both the adult and pediatric age groups. Increased awareness and availability of advanced diagnostic facilities aid in early diagnosis and management. Visual recovery is possible with systemic steroids and immunosuppression. We report the case of a 12-year-old male child who presented with poor vision in his right eye and was found to have retinal striae and disc edema due to posterior scleritis.

Introduction

Scleritis is an uncommon chronic inflammation involving the outermost coat of the eye. Disease can be isolated to the eye, but most often occurs in relation to immune-mediated systemic inflammatory conditions.[1234] It is often extremely painful, vision-threatening and is considered to confer an increased risk of mortality in patients with rheumatoid arthritis. Posterior scleritis represents a diagnostic challenge, requiring a high index of suspicion, and knowledge of the disease.[12345678910111213] Treatment is variable.[12345678910111213]

We report the case of a 12-year-old male child who presented with recurrent redness of his right eye due to posterior scleritis and responded to treatment with systemic steroids.

Case Report

A 12-year-old male child was brought to the Ophthalmology Emergency Clinic with a history of decrease in vision of his right eye (oculus dextrus [OD]) of 1-week duration. There was no history of redness or pain OD. Trauma, ocular surgery or any major systemic disease in past was ruled out. On examination, the best corrected visual acuity OD was −6/9 with (0.25/−0.50 cyl × 90 [no improvement with pin hole]). In the left eye (oculus sinister [OS]) it was 6/5 with 0.50/−0.25 cyl 90. In both eyes (oculus uterque [OU]) anterior segment, direct and consensual pupillary reaction, intraocular pressure (12 mmHg), and extraocular muscle movements were normal. Color vision (Ishihara PseudoIsochromatic Chart) was normal OU.

Amsler chart testing OD showed metamorphopsia but was normal OS. Visual field charting (Humphreys Visual Field Analyzer C-120) was normal OU. Fundus evaluation showed the disparity in the cup-disc ratio (OD 0.1 and OS 0.3). Optic disc OD was hyperemic with blurred margins. There were horizontal striae in the posterior pole between the optic disc and the fovea and the parafoveal and perifoveal region deeper to the retinal blood vessels. The retinal blood vessels and the fovea appeared normal OS [Figure 1a and b], optical coherence tomography (OCT) of macula OD showed folding of the inner retinal layers in the posterior pole, with a central thickness of 254 μ and a parafoveal thickness between 400 and 420 μ. Macular region OS was normal [Figure 2]. B-scan ultrasonography (USG) OD showed diffuse thickening of the choroid and sclera and was normal OS [Figure 3]. Fundus fluorescein angiography (FFA) showed early leakage of the dye from the disc OD and normal dye transit OS [Figure 4]. Magnetic resonance imaging (MRI) of the brain was normal, but right orbit showed diffuse isointense swelling that became hyperintense with contrast on T1-weighted and hypointense on T2-weighted images. The left eye was normal [Figure 5a-c].

Figure 1

(a) Fundus photo oculus dextrus showing disc edema and retinal straie. (b) Fundus photo oculus sinister normal

Figure 2

Optical coherence tomography macula oculus dextrus showing retinal straie, foveal pit is normal

Figure 3

B-scan ultra sound oculus dextrus showing typical “T sign”

Figure 4

Fundus fluorescein angiogram oculus dextrus showing leak from disc

Figure 5

(a) Magnetic resonance imaging brain and orbit – isointense diffuse thickening of right ocular coats. (b) Magnetic resonance imaging brain and orbit – T1-weighted image with contrast – showing hyperintense diffuse thickening of the right ocular coats. (c) Magnetic resonance imaging brain and orbit – T2-weighted image showing hypo intense diffuse thickening of right ocular coats

Complete blood count, differential count, erythrocyte sedimentation rate, C-reactive protein, sickledex, anti-nuclear antibodies, anti-cardiolipid antibodies, rheumatoid antibodies, antiphospholipid antibodies, serology for TORCH, VDRL, were normal. Chest X-ray was normal. Mantoux test was negative. Angiotensin conversion enzyme assay was normal.

A presumptive diagnosis of idiopathic posterior scleritis was made and the patient was treated with pulse methylprednisolone 1 g/day for 3 days followed by oral prednisolone 1 mg/kg body weight. This was tapered gradually over next 8 weeks.

Visual acuity improved to 6/6 (0.25/−0.50 cyl × 90) with a resolution of disc edema and flattening of the retinal striae within 4–6 weeks of initiation of above treatment [Figure 6a and b].

Figure 6

(a) Fundus picture oculus dextrus posttreatment - absent disc edema retinal straie +. (b) Optical coherence tomography macula oculus dextrus - eye – flattening of retinal straie posttreatment

Discussion

Scleritis is an uncommon, destructive inflammation of the sclera, often associated with systemic connective tissue diseases, or potentially lethal vasculitides [Table 1].[12345678910111213] If left untreated, it can cause irreversible visual loss.[123] It has been classified based on anatomical location (anterior and posterior) and nature of involvement (diffuse, nodular, and necrotizing).[12345]

Table 1

Systemic diseases associated with scleritis

Posterior scleritis is inflammation of the sclera posterior to the equator and is often associated with concurrent anterior scleritis.[123456] Incidence rates of scleritis are not well defined yet. However, the prevalence is estimated to be six cases per 10,000 population, with anterior scleritis being more common, occurring in 94% of patients, as opposed to posterior scleritis, which is diagnosed only 6% of the time. The reported average age group of patients with posterior scleritis is 45–49 years.[234] In the pediatric age group, it is rarer compared to adult population, is often idiopathic with no associated systemic disease, or concurrent anterior segment inflammation or pain and occurs both in males and females.[12345678910111213]

Differential diagnosis depends upon the presenting clinical features and includes a wide range of both extraocular and intraocular conditions.[12345678910111213]

Our patient had no pain redness or proptosis; there was a moderate loss of vision with disc edema and retinal folds, absence of dyschromatopsia, visual field defect, and relative afferent pupillary defect and presence of diffuse thickening of the sclera - choroid on MRI and B-scan ultrasound ruled out the diagnosis of optic neuritis/papillitis. Diagnosis of choroidal hemangioma was ruled out by the absence of typical findings on USG and FFA.[678910111213]

Diffuse infiltrating retinoblastoma is rare form presenting at a more advanced age than the typical form (6 years vs. 24 months) and was considered in the differential diagnosis in our case. It is unilateral, sporadic, and more common in boys, between the ages of 1 and 11 years. Pseudo inflammation is a common presenting sign. The reported sonographic findings include retinal detachment, retinal thickening, and nonspecific hyperechogenicity of the vitreous. MRI images show high signal intensity on T1-weighted sequences, low signal intensity on T2-weighted sequences, and moderate contrast enhancement.[13] In our case, the above reported sonographic and MRI findings were absent.[13]

Presenting symptoms and signs of posterior scleritis are variable.[12345] Optic disc edema and retinal striae are common posterior segment findings.[567] Complete resolution of the disease with visual recovery occurs within the 1st year of aggressive systemic corticosteroid therapy. Long-term immune-suppression is often required in most cases to prevent recurrence.[1234567]

Recent studies have led to significant progress in understanding the epidemiology, immunopathogenesis, severity assessment, treatment, and prognosis of this potentially sight-threatening disease.[3456] Wakefield et al. reported scleromalacia perforans as the rarest form of scleritis reaching almost to the point of extinction in some countries. In contrast, they noted that posterior scleritis was more common and recognized more frequently than in the earlier studies, probably due to increased awareness, appreciation of the subtle clinical features and the widespread clinical use of B-mode ultrasound examination of the orbit. The “T sign” on B-scan ultrasound is vital in the diagnosis. However, systemic as well as other ocular investigations such as FFA, OCT, and imaging of brain and orbits are often required to eliminate simulating conditions, and to confirm the diagnosis, as was also in our case.[1234] Significant challenges still exist regarding the understanding of the mechanisms of scleral destruction and inflammation, and the rational approach to the treatment of scleritis. Systemic steroids are the mainstay in the treatment of scleritis and the first line of treatment in posterior scleritis.[1234567891011]

Reports on the role of T- and B-cells, autoantibodies, immune complexes, and cytokines such as tumor necrotic factor (TNF)-alpha in the etiopathogenesis, and clinical trials demonstrating the effectiveness of anti-TNF, anti-B-cell therapy, and systemic immunosuppression, has revolutionized treatment for refractive and recurrent cases.[910111213]

Suppressors of cytokine signaling (SOCS) proteins regulate the intensity and duration of cytokine signals, and their defective expression has been reported in a number of human diseases. Defective expression of SOCS1 has been noted in patients with scleritis, implying that administration of SOCS1 mimetic peptides may be useful in treating scleritis in the future.[11] Posterior scleritis in the pediatric age group is rare and a diagnostic challenge to the ophthalmologist, requiring a high index of suspicion and awareness with extensive systemic and ocular investigations.[12345] B-scan ultrasound is an important investigation in the diagnosis. MRI, FFA, and OCT aid in diagnosis by eliminating simulating conditions.[12345678]

Early diagnosis and prompt treatment with high dose of systemic steroids lead to complete visual recovery as was seen in our case. Immunosuppression is required in refractory and recurrent cases. Posterior scleritis though uncommon should be considered in the differential diagnosis of acute orbital inflammation in the pediatric age group.[910111213]

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