Elsevier

Ophthalmology

Volume 120, Issue 1, January 2013, Pages 100-105
Ophthalmology

Original article
Clinical Evidence of Sustained Chronic Inflammatory Reaction in Retinitis Pigmentosa

https://doi.org/10.1016/j.ophtha.2012.07.006Get rights and content

Purpose

To study the nature of inflammatory reaction in eyes of patients with retinitis pigmentosa (RP) and its possible role in the pathogenesis of RP.

Design

Retrospective, observational study.

Participants and Controls

Three hundred seventy-one consecutive patients diagnosed with typical RP were included in this study. We included 165 patients without active inflammatory diseases, including 20 patients diagnosed with cataract, and 36 patients diagnosed with idiopathic epiretinal membrane as controls.

Methods

Density of the inflammatory cells in the anterior vitreous cavity was measured and graded by slit-lamp biomicroscopy. A multiplex enzyme-linked immunosorbent assay (ELISA) was performed to evaluate the concentration of cytokines and chemokines in aqueous humor and vitreous fluid of patients with RP and controls. In addition, we investigated the relationship between visual function and anterior vitreous cells in these patients.

Main Outcome Measures

Slit-lamp biomicroscopic analysis, best-corrected visual acuity, visual field analysis, and multiplex ELISA.

Results

In 190 of 509 eyes with RP (37.3%), “1+” (5–9 cells per field) or more cells were observed in the anterior vitreous cavity. Strong inflammatory reaction with “2+” cells (10–30 cells per field) was associated with younger age. In the elderly patients with RP, significantly decreased visual function was seen in a group with “1+” or more cells (P<0.05). Moreover, the levels of a variety of proinflammatory cytokines and chemokines, including monocyte chemotactic protein-1, were increased both in the aqueous humor and vitreous fluid of RP patients compared with the levels in control patients.

Conclusions

Sustained chronic inflammatory reaction may underlie the pathogenesis of RP, suggesting interventions for ocular inflammatory reaction as a potential treatment for patients with RP.

Financial Disclosure(s)

The authors have no proprietary or commercial interest in any of the materials discussed in this article.

Section snippets

Patients

This retrospective study included 371 consecutive patients (167 male and 204 female) diagnosed with typical RP, as well as 165 control patients (89 male and 76 female) without active inflammation-associated diseases, such as uveitis or proliferative diabetic retinopathy. Eyes with a history of intraocular operation were excluded. The characteristics of these patients are shown in Table 1. All patients in this study were seen at Kyushu University Hospital (Fukuoka, Japan). Written, informed

Density of Inflammatory Cells in the Anterior Vitreous by Slit-lamp Biomicroscopy

We assessed the inflammatory cell density in the anterior vitreous cavity of 371 RP patients and 165 control patients by slit-lamp biomicroscopy. The distribution of density of inflammatory cells according to age is shown in Figure 1. Occasional or more cells in the vitreous cavity were identified in 61.5% (313 eyes) of 509 eyes with RP; 1+ or more cells were observed in 37.3% (190 eyes). There was no patient with 3+ or more cells. Notably, stronger inflammatory reaction with 2+ cells were more

Discussion

Retinitis pigmentosa is a heterogeneous group of inherited retinal diseases resulting in adult blindness. Although various genetic mutations have been identified in patients with RP, the mechanisms by which these mutations lead to photoreceptor apoptosis remain largely unknown. Previous studies have reported the presence of an inflammatory reaction in the eyes of patients with RP.7, 8 However, the relationship between inflammation and visual function and the underlying molecular changes has not

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    Manuscript no. 2011-1790.

    Financial Disclosure(s): The authors have no proprietary or commercial interest in any of the materials discussed in this article.

    Supported in part by a Grant-in-Aid (to Y.I. and T.I.) from the Japanese Ministry of Education, Culture, Sports, Science, and Technology (#20791259, #24659763, and #24659764).

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