Intravitreal bevacizumab (Avastin) as primary and rescue treatment for choroidal neovascularization secondary to ocular toxoplasmosis

Clinical outcomes of intravitreal treatment for ocular toxoplasmosis: systematic review and meta-analysis

BACKGROUND

Ocular toxoplasmosis is the leading cause of infectious posterior uveitis worldwide, accounting for 30-50% of all cases in immunocompetent patients. Conventional treatment is associated with adverse effects and does not prevent recurrence. Intravitreal drug administration can improve disease outcomes and reduce side effects. Herein, we conducted a systematic review and meta-analysis on the efficacy of intravitreal injections for treating ocular toxoplasmosis.

METHODS

The systematic search was conducted using PubMed, SciELO, and Google Scholar with the descriptors "ocular toxoplasmosis" AND "intravitreal". We analyzed studies that met the inclusion criteria, i.e., experimental cases in patients treated intravitreally for ocular toxoplasmosis. Considering the systematic review, we focused on the number of intravitreal injections, the therapeutic drug class, and the presence of preexisting conditions. To assess the efficacy of intravitreal injections, a meta-analysis was performed using visual acuity, side effects, disease recurrence, and inflammatory responses as variables.

RESULTS

Intravitreal injection-induced side effects were rarely observed (0.49% [0.00, 1.51%] ). The use of antiparasitic and anti-inflammatory drugs afforded improved visual acuity (99.81% [98.60, 100.00%]) and marked effectiveness in treating ocular toxoplasmosis.

CONCLUSIONS

Intravitreal injections may facilitate the successful treatment of ocular toxoplasmosis. However, clinicians should carefully evaluate the presence of preexisting conditions for ocular toxoplasmosis or previous diseases, as these can impact the decision to administer intravitreal injections.

VEGF Production Is Regulated by the AKT/ERK1/2 Signaling Pathway and Controls the Proliferation of Toxoplasma gondii in ARPE-19 Cells

The retina is the primary site of Toxoplasma gondii infection in the eye, and choroidal neovascularization in ocular toxoplasmosis is one of the most important causes of visual impairment. Vascular endothelial growth factor (VEGF) is one of the key regulators of blood vessel development, however, little is known about the mechanisms of T. gondii-induced VEGF production in ocular toxoplasmosis. Here, we investigate the effect of T. gondii on VEGF production regulation in human retinal pigment epithelium ARPE-19 cells and attempted to unveil the underlying mechanism of this event by focusing on the interaction between parasite and the selected host intracellular signaling pathways. T. gondii infection increased the expression of VEGF mRNA and protein in ARPE-19 cells in parasite burden- and infection time-dependent manner. The proportional increase of VEGF upstream regulators, HIF-1α and HO-1, was also observed. T. gondii induced the activation of host p-AKT, p-ERK1/2, and p-p38 MAPK in ARPE-19 cells in a parasite-burden dependent manner. However, VEGF expression decreased after the pre-treatment with PI3K inhibitors (LY294002 and GDC-0941), ERK1/2 inhibitor (PD098059), and p38 MAPK inhibitor (SB203580), but not JNK inhibitor (SP600125), in a dose-dependent manner. The anti-VEGF agent bevacizumab or VEGF siRNA transfection prominently inhibited the activation of p-AKT and p-ERK1/2, but not p-p38 MAPK and JNK1/2 in T. gondii-infected ARPE-19 cells. Bevacizumab treatment or VEGF siRNA transfection significantly inhibited the proliferation of T. gondii tachyzoites in the host cell, dose-dependently, but not invasion of parasites. VEGF-receptor 2 (VEGF-R2) antagonist, SU5416, attenuated VEGF production and tachyzoite proliferation in T. gondii-infected ARPE-19 cells in a dose-dependent manner. Collectively, T. gondii prominently induces VEGF production in ARPE-19 cells, and VEGF and AKT/ERK1/2 signaling pathways mutually regulate each other in T. gondii-infected ARPE-19 cells, but not p38 MAPK and JNK1/2 signaling pathways. VEGF and VEGF-R2 control the parasite proliferation in T. gondii-infected ARPE-19 cells. From this study, we revealed the putative mechanisms for VEGF induction as well as the existence of positive feedback between VEGF and PI3K/MAPK signaling pathways in T. gondii-infected retinal pigment epithelium.

An update on inflammatory choroidal neovascularization: epidemiology, multimodal imaging, and management

Inflammatory choroidal neovascular membranes are challenging to diagnose and manage. A number of uveitic entities may be complicated by the development of choroidal neovascularization leading to a decrease in central visual acuity. In conditions such as punctate inner choroidopathy, development of choroidal neovascularization is extremely common and must be suspected in all cases. On the other hand, in patients with conditions such as serpiginous choroiditis, and multifocal choroiditis, it may be difficult to differentiate between inflammatory choroiditis lesions and choroidal neovascularization. Multimodal imaging analysis, including the recently introduced technology of optical coherence tomography angiography, greatly aid in the diagnosis and management of inflammatory choroidal neovascularization. Management of these neovascular membranes consists of anti-vascular growth factor agents, with or without concomitant anti-inflammatory and/or corticosteroid therapy.

OCTA Imaging of Choroidal Neovascular Membrane Secondary to Toxoplasma Retinochoroiditis

Two patients (a 37-year-old man and a 28-year-old woman) who had choroidal neovascular membrane (CNVM) secondary to inactive toxoplasma retinochoroiditis scarring were evaluated. Multimodal imaging including fluorescein angiography, optical coherence tomography (OCT), and OCT angiography (OCTA) was used. CNVM secondary to inactive toxoplasma retinochoroiditis scarring was detected. Representative images of CNVM were demonstrated in the outer retinal layer and choriocapillary layer on OCTA. OCTA, a relatively new technique, is useful in the diagnosis of the CNVMs secondary to retinochoroiditis. [Ophthalmic Surg Lasers Imaging Retina. 2017;48:509-511.].

Intravitreal aflibercept for choroidal neovascularization associated with chorioretinitis: a pilot study

Purpose

The purpose of this study was to evaluate the potential benefits of intravitreal aflibercept injections for the treatment of choroidal neovascularization (CNV) secondary to chorioretinitis.

Methods

In this uncontrolled, prospective cohort study, 15 eyes of 14 consecutive patients affected by CNV associated with ocular toxoplasmosis were treated with intravitreal aflibercept (2 mg) pro re nata and observed over a 12-month follow-up period. The primary outcome was the change in best-corrected visual acuity (BCVA) from baseline to month 12. Secondary outcomes included change in central retinal thickness (CRT) in the foveal area on optical coherence tomography (OCT) from baseline to month 12, the number of intravitreal aflibercept injections administered, and safety.

Results

Mean (standard deviation [SD]) BCVA improved significantly from 0.36 (0.23) at baseline to 0.64 (0.3) at month 12 (P=0.0002). Mean (SD) CRT on OCT showed a reduction from 317 (74) µm at baseline to 254 (43) µm (P=0.0002) at month 12. A mean (SD) of 1.7 (0.5) injections (range, 1–2 injections) were performed during the study period. No cases of endophthalmitis, uveitis, stroke, or retinal detachment were noted. No patient demonstrated an intraocular pressure >20 mmHg at any study visit.

Conclusion

Intravitreal aflibercept showed a positive clinical effect and was well tolerated for the treatment of CNV associated with chorioretinitis. The results could be helpful for selecting a treatment for CNV secondary to chorioretinitis.

Intravitreal bevacizumab for treatment of choroidal neovascularization secondary to toxoplasmic retinochoroiditis: a case series

PURPOSE

To evaluate the efficacy and safety of intravitreal bevacizumab (Avastin) in treatment of choroidal neovascularization (CNV) secondary to toxoplasmic retinochoroiditis.

DESIGN

Prospective case series.

METHODS

Four patients affected by CNV secondary to inactive toxoplasmic retinochoroiditis received 1.25 mg intravitreal bevacizumab and were followed for at least six months. Patients underwent a full ophthalmic examination and fluorescein angiography (FA) and optical coherence tomography (OCT), revealing an active subfoveal CNV close to an old chorioretinal scar. All the patients were positive for toxoplasma immunoglobulins. Outcome measures were changes in best-corrected visual acuity (BCVA) and central macular thickness (CMT) and any adverse event related to the therapy.

RESULTS

CNV regressed at eight weeks of follow-up and remained stable at six months of follow-up. Best-corrected visual acuity improved from mean 0.05 to 0.25. After six months, the BCVA improved in all patients (p < 0.05) and CMT decreased from 396 +/-7 micron to 253+/-17 micron. Metamorphopsia was resolved in all cases.

CONCLUSIONS

Intravitreal bevacizumab seems to be an effective treatment for the long-term control of juxta/subfoveal CNV secondary to toxoplasmic retinochoroiditis. Further trials are mandatory to validate the data of our case series.

Three-year visual and anatomic results of administrating intravitreal bevacizumab in inflammatory ocular neovascularization

OBJECTIVE

To assess the 3-year visual outcome of intravitreal bevacizumab in inflammatory ocular neovascularization.

DESIGN

Experimental study.

METHODS

Retrospective multicenter consecutive case series in 81 patients with inflammatory ocular neovascularization refractory to standard therapy and treated with intravitreal bevacizumab. The outcome measures included improvement of best corrected visual acuity expressed as logarithm of minimum angle of resolution (logMAR) and paired comparison decrease in central foveal thickness by optical coherence tomography.

RESULTS

Mean best corrected visual acuity improved from baseline 0.699 (6/30 or 20/101) (SD 0.434) to 0.426 (6/16 or 20/53) (SD 0.428) (n = 81; p < 0.001), a gain of 2.7 lines (median 3 injections; 81 eyes; 81 patients). Paired comparisons revealed significant central foveal flattening at 3 years of 97.9 μm (n = 51; p < 0.001). In a subgroup analysis, visual improvement was significant for ocular histoplasmosis (p = 0.026); multifocal choroiditis (p = 0.05); serpiginous choroiditis (p = 0.028); ocular toxoplasmosis (p = 0.042); and punctate inner choroidopathy (p = 0.015). In a subgroup analysis, foveal flattening was significant for ocular histoplasmosis (p = 0.004); multifocal choroiditis (p = 0.007); serpiginous choroiditis (p = 0.011); and punctate inner choroidopathy (p = 0.001). Of the group, 5 eyes developed submacular fibrosis, 1 eye retinal pigment epithelial tear, and 1 eye macular ischemia in the context of vasculitis.

CONCLUSION

At 3 years, intravitreal bevacizumab sustained significant visual improvement of 2.7 lines and significant foveal flattening of 98 μm in a wide variety of inflammatory ocular diseases without major complications after a median of 3 injections.

Five-year visual results of intravitreal bevacizumab in refractory inflammatory ocular neovascularization

Purpose

To assess the 5-year visual outcome of intravitreal bevacizumab in inflammatory ocular neovascularization.

Methods

Retrospective, multicenter, consecutive case series of eight patients with inflammatory ocular neovascularization refractory to standard therapy who were treated with intravitreal bevacizumab and followed for 5 years after first injection. The outcome measures included improvement of best-corrected visual acuity expressed as logarithm of minimum angle of resolution.

Results

Mean best-corrected visual acuity significantly improved from 0.58 at baseline (6/23 or 20/76; standard deviation = 0.32) to 0.20 at final assessment (6/10 or 20/32; standard deviation = 0.25) (n = 8; P = 0.02), a gain of 3.8 lines (median: three injections; eight eyes; eight patients). No ocular or systemic complications from intravitreal bevacizumab were noted.

Conclusion

At 5 years, intravitreal bevacizumab sustained significant visual improvement in ocular neovascularization due to a variety of inflammatory ocular diseases without major complications after a median of three injections.

Intravitreal ranibizumab for the treatment of choroidal neovascularization secondary to ocular toxoplasmosis

The purpose of the study was to report a case of choroidal neovascularization (CNV) secondary to ocular toxoplasmosis in an 18-year-old female patient. She was treated with a single intravitreal injection of ranibizumab. The CNV resolved as confirmed by fluorescein angiography and optical coherence tomography (OCT). The visual acuity improved to 20/30, which was maintained till the last follow-up visit at two years, without requisition of a repeat injection.

Clinical manifestations of ocular toxoplasmosis

Clinical manifestations of ocular toxoplasmosis are reviewed. Findings of congenital and acute acquired ocular toxoplasmosis include retinal scars, white-appearing lesions in the active phase often associated with vitritis. Complications can include fibrous bands, secondary serous or rhegmatogenous retinal detachments, optic neuritis and neuropathy, cataracts, increased intraocular pressure during active infection, and choroidal neovascular membranes. Recurrences in untreated congenital toxoplasmosis occur in teenage years. Manifestations at birth are less severe, and recurrences are fewer in those who were treated promptly early in the course of their disease in utero and in the first year of life. Severe retinal involvement is common at diagnosis of symptomatic congenital toxoplasmosis in the United States and Brazil. Acute acquired infections also may be complicated by toxoplasmic retinochoroiditis, with recurrences most common close to the time of acquisition. Suppressive treatment can reduce recurrent disease.

Inflammatory choroidal neovascularization

Purpose and Methods:

Choroidal neovascularization (CNV) can be a severe sight-threatening sequela, which can be secondary to both infectious and noninfectious uveitis. This review summarizes the different diseases associated with CNV, highlighting new treatment modalities and the possible strategies, which could be applied for the therapy of this occurrence.

Results:

Since CNV can often originate from posterior pole lesions and can be hard to identify, an accurate examination is mandatory in order to identify the correct diagnosis. In the majority of cases, fluorescein angiography (FA), indocyanine green angiography (ICGA) and optical coherence tomography (OCT) enable the determination of the clinical characteristics of the CNV. An infectious disease should be looked for to include a suitable therapy when available. The treatment strategy for CNV secondary to noninfectious uveal inflammations should be directed at controlling the inflammatory process. Systemic corticosteroids with or without immunosuppressive agents are indicated even when the CNV occurs with apparently inactive uveitis: Chronic subclinical inflammation can be the basis for the pathogenesis of CNV. Additional therapies aimed directly at the neovascular process, such as the intravitreal anti-Vascular Endothelial Growth Factor (VEGF) agents, are recommended particularly when the therapy shows an insufficient response.

Conclusion:

CNV secondary to uveitis is a severe sequela leading to significant visual impairment. ICGA is mandatory in order to obtain relevant information about the choroidal status. Several therapeutic options have been considered, but no guidelines are provided at the moment. Moreover, the current data are still only based on case reports or small series. For such reasons, further trials are mandatory to validate the preliminary available results.

Combination photodynamic therapy and bevacizumab for choroidal neovascularization associated with toxoplasmosis

A 14-year-old girl presenting with visual loss in both eyes was diagnosed to have healed toxoplasma retinochoroiditis in the right eye with active choroidal neovascularization (CNV) secondary to toxoplasmosis in the left. She underwent combination photodynamic therapy (PDT) and intravitreal bevacizumab as primary treatment. PDT was performed as per the 'Treatment of Age-related Macular Degeneration by Photodynamic therapy' study protocol and was followed by intravitreal bevacizumab after 2 days. CNV regressed at 8 weeks of follow-up and remained stable at 8 months of follow-up. The initial visual acuity improved from 20/120 to 20/30. Combination therapy with PDT and intravitreal bevacizumab appears to be effective in the treatment of CNV secondary to toxoplasma retinochoroiditis.

Long-term visual outcomes of intravitreal bevacizumab in inflammatory ocular neovascularization

PURPOSE

To assess the long-term role of bevacizumab (Avastin; Genentech Inc, South San Francisco, California, USA) in inflammatory ocular neovascularization.

DESIGN

Retrospective multicenter consecutive case series of inflammatory ocular neovascularization.

METHODS

settings: Multicenter institutional and private practices.

STUDY POPULATION

Patients with inflammatory ocular neovascularization in one or both eyes of varying etiologies who failed standard therapy. intervention: Intravitreal injection of bevacizumab.

MAIN OUTCOME MEASURES

Improvement of best-corrected visual acuity (BCVA) expressed as logarithm of minimal angle of resolution (logMAR), and decrease in central foveal thickness as measured by optical coherence tomography at 6, 12, 18, and 24 months of follow-up.

RESULTS

Mean logMAR BCVA (central foveal thickness) following intravitreal bevacizumab was as follows: baseline, 0.65 (6/27 or 20/90) (338 microm; 99 eyes of 96 patients); 6 months, 0.42 (6/16 or 20/53) (239 microm; 2.0 injections; 81 eyes); 12 months, 0.39 (6/15 or 20/49) (241 microm; 2.3 injections; 95 eyes); 18 months, 0.40 (6/15 or 20/50) (261 microm; 3.0 injections; 46 eyes); and 24 months, 0.34 (6/13 or 20/44) (265 microm; 3.6 injections; 27 eyes). Paired comparisons revealed significant visual improvement at 6 months of 2.4 lines (P = .000), at 12 months of 2.5 lines (P = .000), at 18 months of 2.5 lines (P = .001), and at 24 months of 2.2 lines (P = .013). Paired comparisons revealed significant central foveal flattening at 6 months of 78 microm (P = .000), at 12 months of 85 microm (P = .000), at 18 months of 90 microm (P = .003), and at 24 months of 77 microm (P = .022). Three eyes developed submacular fibrosis and 1 eye submacular hemorrhage.

CONCLUSION

Intravitreal bevacizumab led in the long-term to significant mean visual improvement of > or =2.2 lines and significant foveal flattening in a wide variety of inflammatory ocular diseases without major complications.

Bevacizumab (Avastin) for the treatment of ocular disease

The use of intravitreal bevacizumab (Avastin) has greatly expanded since its introduction into ophthalmic care 3 years ago. A PubMed search on 1 August 2008 revealed 51 ocular disease processes that have been treated with bevacizumab. The majority of publications consist of case reports or retrospective case series and their number is increasing quickly. It is important to collate the experiences gained to date to properly inform our clinical decision making and improve the design of future clinical trials. Current studies cannot easily be combined in a meta-analysis given the lack of standardized data and the wide variety of disorders studied in small numbers. This paper will describe the attempted uses of intravitreal bevacizumab and its efficacy for each ocular disease in addition to discussing safety. Comments regarding appropriate use of this treatment are based on our current level of knowledge. It is clear that the initial encouraging results described in this paper warrant further study of intravitreal bevacizumab in larger, controlled, randomized trials.

Long-term control of choroidal neovascularization in quiescent congenital toxoplasma retinochoroiditis with photodynamic therapy: 4-year results

PURPOSE

To evaluate the efficacy and safety of photodynamic therapy (PDT) in the long-term control of subfoveal choroidal neovascularization (CNV) associated with toxoplasmic retinochoroiditis.

METHODS

The records of 13 patients with classic subfoveal CNV associated with toxoplasmic retinochoroiditis treated with PDT were reviewed. All patients were followed up for at least 48 months. Postoperative visual acuity was defined as a gain or loss of two or more lines of best-corrected visual acuity (BCVA), respectively. Post-treatment CNV size was dichotomized into "increased" if the major CNV diameter (CMD) had increased by >or=300 microm, and as "stable/reduced" if it had decreased by >or=300 microm or had not changed by >300 microm.

RESULTS

Nine patients [four males (44.4%) and five females (55.6%)] with a mean age of 20.1 +/- 4.3 years (range 14-27 years) were enrolled in the study. All had unilateral involvement. The median follow-up was 55 months (minimum 48, maximum 65 months). At the 48-month follow-up, all patients had stable/improved BCVA and a mean stable/reduced CMD (846 +/- 326.5 microm), with the BCVA having improved significantly (p < 0.0001) from 0.29 +/- 0.19 at baseline to 0.54 +/- 0.16 at 48 months.

CONCLUSION

Photodynamic therapy seems to be a safe and effective approach to the long-term control of subfoveal CNV associated with toxoplasmic retinochoroiditis. Further trials are needed to validate these findings.