Clinical characteristics and visual outcomes in infectious scleritis: a review

Abstract

Infection is a very important but rare cause of scleritis, occurring in about 5%-10% of all patients presenting with scleral inflammation. However, due to the similarity of its presentation, infectious scleritis is often initially managed as autoimmune, potentially further worsening its outcome. The overall visual outcome in infectious scleritis is generally worse than its autoimmune counterparts, perhaps because of the delay in diagnosis or because of the aggressive nature of associated microbes. Thus, there is a definite need for insight into the diagnostic approach and treatment options for this ocular disease process. Several studies and case reports have been published in recent years that have provided useful information regarding the presenting clinical features and etiologic microbial agents in infectious scleritis. This review summarizes the important findings in the literature that may aid in differentiating infectious scleritis from other etiologies, including predisposing factors, microbe-specific characteristics, diagnostic tools, treatment modalities, and outcomes.

Keywords: Pseudomonas; abscess; infectious scleritis; necrotizing scleritis.

Figure 1

Scleral ulcer with calcific plaque. Notes: (A) At presentation, there was a calcific plaque over the scleral ulcer bed (arrowhead). The ulcer progressed and became contiguous with a corneal infiltrate (arrow). (B) Multiple new nodules (arrowheads) from which P. aeruginosa was cultured, appeared on the 22nd day of hospitalization. ©1998 BMJ Publishing Group. Reproduced with permission from Hsiao CH, Chen JJ, Huang SC, Ma HK, et al. intrascleral dissemination of infectious scleritis following pterygium excision. Br J Ophthalmol. 1998;82(1):29–34.

Figure 2

Slit lamp pictures depicting different clinical presentation. Notes: (A) Case no 2: multiple scleral abscess. (B) Case no 12: single scleral abscess. (C) Case no 4: necrotic ulcer (post cataract surgery). (D) Case no 3: two punched out ulcers. Reproduced with permission from Kumar SS, Das S, Sharma S et al. Clinico-microbiological profile and treatment outcome of infectious scleritis: experience from a tertiary eye care eye center of india. Int K Inflam. 2012:753560.

Figure 3

Case 1: Scleral thinning from original ulcer through subsequent abscess extended in an arc shape. Note: © 1998 BMJ Publishing Group. Reproduced with permission from Hsiao CH, Chen JJ, Huang SC et al. Intrascleral dissemination of infectious scleritis following pterygium excision. Br J Ophthalmol. 1998;82(1):29–34.

Figure 4

Visual acuities before and after treatment. Notes: Patients with infectious necrotizing scleritis had the poorest BCVA before and after treatment. The data are presented as the mean ± standard deviation. Reproduced with permission from Ahn SJ, Oh JY, Kim MK, Lee JH, Wee WR. Clinical features, predisposing factors, and treatment outcomes of scleritis in the Korean population. Korean J Ophthalmol. 2010;24(6):331–335. Abbreviations: BCVA, best corrected visual acuities; logMAR, logarithmic value of the minimal angle of resolution.

Figure 5

Advanced imaging studies of complications of infectious scleritis. Notes: (A) 35 MHz immersion ultrasound biomicroscopy demonstrating shallow anterior chamber, thickened and anteriorly rotated ciliary body (arrow), and elimination of the ciliary sulcus. (B) Thickened episcleral, scleral, and choroidal tissues are evident in the magnified view. (C) 10 MHz B-scan ultrasonography showing double retinal and choroidal detachment, L-12 view, (D) L-mac view, and (E) spectral optical coherence tomography showing vitreous clumps (dotted arrows and circles), subretinal fluid, and subretinal precipitates (solid arrow). Reproduced with permission from Nguyen P, Yiu SC. Imaging studies in a case of infectious scleritis after pterygium excision. Middle East Afr J Ophthalmol. 2012;19(3): 337–339. Abbreviations: L-12, longitudinal-12 view; L-mac, longitudinal-macular view.

Figure 6

Scleral ulcer before and after debridement Notes: (A) The scleral ulceration located at the 9 o’clock position. Severe congestion and subconjunctival abscess were noted at 10 o’clock position under the biomicroscope. (B) After the surgical debridement, the scleral wound was left open. in comparison with (A), the involved area was more extensive. (C) Ten days later, the debrided area was healing. © 1997 BMJ Publishing Group. Reproduced with permission from: Lin CP, Shih MH, Tsai MC. Clinical experiences of infectious scleral ulceration: a complication of pterygium operation. Br J Ophthalmol. 1997;81(11):980–983.