By Ramana S. (Bob) Moorthy, MD
This study published in January in Ophthalmology provides a thorough review of posterior scleritis in children and retrospectively evaluates the largest pediatric cohort to date with this condition. Visual outcomes were favorable and common features of posterior scleritis included concurrent anterior uveitis, disc swelling and retinal striae. B-scan ultrasound demonstrating T-sign was the most useful confirmatory investigation in all cases. Aggressive systemic corticosteroid therapy achieved resolution in most cases within the first year, although long-term immunosuppression was often required to prevent recurrence.
This report focuses on an important cohort that can develop posterior scleritis. It was of particular interest to me since I tend to see more adults with posterior scleritis (often women in their third to fifth decades) than children. However, I find it clinically difficult to differentiate posterior scleritis from other workup-negative entities that also respond to corticosteroids and immunotherapy, such as orbital inflammatory syndrome or Vogt-Koyanagi-Harada syndrome (VKH) with posterior scleritis, which may also have a positive T-sign on B-mode ultrasonography.
The study reports on a retrospective case series of 13 patients (20 eyes) ranging in age from 5 to 16 years who were seen at an ocular immunology and inflammation clinic in Singapore. The median presenting vision was 20/30. No underlying connective tissue disorder was diagnosed in any patient.
Scleritis resolved with oral nonsteroidal anti-inflammatory treatment alone in one patient (8 percent). Twelve patients (92.3 percent) received oral corticosteroids. Immunosuppressive agents were required in 11 patients (84.6 percent) because of relapse or intolerance to corticosteroid. The median final vision at one year was 20/20. Seven patients (63.6 percent) remained on immunosuppression at the latest follow-up at a median of four years.
Four patients (31 percent) had limitation of ocular motility, which suggests orbital myositis. Did these patients only have posterior scleritis or a form of orbital inflammatory syndrome? Although 80 percent of eyes had anterior uveitis, no mention is made of vitreous inflammation. That seems somewhat unusual, since anterior segment inflammation is mild and variable in posterior scleritis. Could these have been cases of mild panuveitis? These issues remain somewhat unclear.
Although the authors performed ancillary testing that was sufficient to rule in the diagnosis of posterior scleritis, details are not given regarding how conditions, such as VKH, sarcoidosis posterior scleritis or orbital inflammatory syndrome, were ruled out. All of these conditions may have similar ultrasonographic, fluorescein angiographic and clinical characteristics, and they are an integral part of the differential diagnosis of this condition. In fact, some cases of VKH, a condition more common in Southeast Asia, can (by contiguous extension of posterior choroidal inflammation) be associated with bilateral posterior scleritis, and these cases may be impossible to differentiate.
My experience with treatment has been similar to the authors', with most patients responding nicely initially to corticosteroids but recurring with discontinuation and requiring either low-dose maintenance corticosteroids and/or long-term immunotherapy (four to five years or longer on average). Children with posterior scleritis do tend to maintain good vision and minimal macular complications when treated aggressively. In my experience, adults can occasionally develop long-term visual loss due to permanent macular striae, retinal pigment epithelium changes and macular scarring. These findings were rare in children in this and other reports.
The authors also performed an extensive literature review, identifying 14 relevant papers on posterior scleritis in patients younger than 21 years. They describe the new combined cohort of 38 patients (54 eyes), including their 13 patients. Systemic laboratory investigations were positive in 24 percent, mainly including their own cohort. Forty-eight percent of eyes had anterior uveitis; 19 percent had anterior scleritis. Posterior segment manifestations included disc swelling in 80 percent, retinal striae in 39 percent and serous retinal detachment in 26 percent.
Immunotherapy was used in 44 percent of the combined cohort. One patient received infliximab and recurred despite immunosuppression. Final visual acuity was a median of 20/20 (range, 20/15 to no light perception), with 93 percent of eyes recovering vision of better than 20/40. Presenting visual acuities were also variable (20/20 to no light perception) and may have been related to delays in diagnosis.