Abstract

Cystoid Macular Edema (CME) is a common complication of Retinitis Pigmentosa (RP) which increases with time and its treatment remains a challenge. Aberrant inflammation plays an essential role in RP. Here we report that local application of etamsylate, a powerful anti-inflammatory medicament, led to clinical improvement in a patient presenting this condition.

Keywords: Retinitis Pigmentosa; Etamsylate; Fibroblast Growth Factor

Introduction

RP is a genetic progressive disease characterized by the death of photoreceptors that produces night blindness and finally a total vision loss in both eyes [1]. This disease affects 2 million people in the world [2]. This condition is characterized with photophobia, central visual constriction, mid-peripheral bone spicula pigmentation, optic disc pallor and attenuation of retinal arteries at fundus oculi examination. CME is a common complication of RP that occurs in 10% to 38% of patients [3].

Chronic inflammation plays a deleterious effect on the retinal function as such occurs in RP [4]. Thus, reduction of retinal inflammation emerges as a new therapeutic target to reduce the deleterious effects in RP. In this study, we assess the efficacy of etamsylate, a powerful anti-inflammatory drug in a RP patient [5,6].

Case Presentation

A female with 36 years history of RP presented at the Hospital Pio XII (Madrid. Spain). Having signed her consent, patient was ophthalmologically examined. Spectral-Domain of Optical Coherence Tomography (SD-OCT) and Best-Corrected Visual Acuity (BCVA) were performed. Patient received an intravitreal injection of etamsylate (150 µl) (Sanofi-Aventis. Paris. France) in her left eye. At baseline SD-OCT showed a parafoveal cystoid macular edema in the nasal portion (Fig. 1) and BCVA was 0.1. Ten days after treatment macular edema disappeared (Fig. 1) and BC-VA was 0.3. 

Figure 1: Spectral-Domain of Optical Coherence Tomography (SD-OCT) demonstrated macular edema at baseline (A, rectangle). After 10 days of etamsylate treatment macular edema disappeared (B, rectangle). 

Discussion

Retinal inflammation is characterized by the proliferation and migration of glial cells and the synthesis of inflammatory molecules which affects the retinal function [7]. Repeated intravitreal ranibizumad (an anti-VEGF drug) has been used in patients with RP [8]. However, no significant improvement was noted in visual acuity beyond 6 months.

Etamsylate is a well characterized inhibitor of Fibroblast Growth Factor (FGF) that has demonstrated safety and efficacy in different human inflammatory-dependent diseases [5,6,9-11]. We have showed that etamsylate interact with both FGF and its receptors, displacing heparin from its binding site, modifying the tri-dimensional structure of the protein and its receptor recognizing site and consequently, dissociating the receptor-growth factor signalling complex [5]. These properties may account for the efficacy of the treatment. Therefore, etamsylate therapy could be an attractive option in treating retinitis pigmentosa.  

Conclusion

RP is characterized by degeneraiton of rod and cone photoreceptors that progresses to irreversible blindness. Etamsylate is an old medicament showing marked anti-inflammatory activity that can interrupt inflammatory network in the onset and progression of retinitis pigmentosa.

Conflict of Interest

The authors declared no potential conflicts of interest with respect to the research, authorship and/or publication of this article.

Funding Statement

This research did not receive any specific grant from funding agencies in the public, commercial or non-profit sectors.

Acknowledgement

None.

Data Availability Statement

Not applicable.

Ethical Statement

The project did not meet the definition of human subject research under the purview of the IRB according to federal regulations and therefore was exempt.

Informed Consent Statement

Informed consent was not required for this study due to the use of anonymized data with no identifiable personal information.

Authors’ Contributions

PC wrote the article. LO performed the clinical study and JA prepared the iconography.

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