Elevated C-Reactive Protein Levels in Patients with Polypoidal Choroidal Vasculopathy and Patients with Neovascular Age-Related Macular Degeneration

Is age-related macular degeneration a manifestation of systemic disease? New prospects for early intervention and treatment

Age-related macular degeneration (AMD) is a common vision-threatening condition affecting the elderly. AMD shares common risk factors and processes, including vascular and inflammatory pathways, with many systemic disorders. Associations have been reported between AMD and hypertension, cardiovascular disease, cerebrovascular disease, dyslipidaemia, chronic kidney disease and neurodegenerative disorders. An increasing amount of evidence suggests that individuals with AMD are also at risk of systemic diseases such as stroke. In this review, we summarize the latest evidence to support the notion that AMD is an ocular manifestation of systemic disease processes, and discuss the potential systemic side effects of ocular AMD therapy of which general physicians should be aware. Recent genetic discoveries and understanding of the pathogenic pathways in AMD in relation to systemic disorders are also highlighted.

Three-year visual outcome of photodynamic therapy plus intravitreal bevacizumab with or without subtenon triamcinolone acetonide injections for polypoidal choroidal vasculopathy

PURPOSE

To compare the 3-year visual outcome after double therapy of photodynamic therapy (PDT) with intravitreal bevacizumab (IVB) and triple therapy of PDT combined with IVB and subtenon triamcinolone acetonide (STTA) injections for polypoidal choroidal vasculopathy (PCV).

DESIGN

Retrospective, comparative, interventional case series.

METHODS

Medical records for 36 eyes in 36 patients (33 men, 3 women; mean age 73.5 years old; range 63-82 years old) with treatment-naive subfoveal PCV were reviewed retrospectively. Of the 36 eyes, 17 were treated with double therapy and 19 with triple therapy.

RESULTS

The change in visual acuity after triple therapy was significantly better than that after double therapy (p<0.05). At 36 months, improvement in visual acuity was seen in 5 eyes (29.4%) in the double therapy group and 10 eyes (52.6%) in the triple therapy group. Retreatment using the initial treatment was performed for six eyes (35.3%) in the double therapy group and five eyes (26.3%) in the triple therapy group, and treatment-free period was significantly longer in the triple therapy group (p<0.05). The mean number of additional antivascular endothelial growth factor therapy was higher in the double therapy group. Post-treatment vitreous haemorrhage or retinal pigment epithelium tear occurred only in the double therapy group, in one eye (5.9%) and one eye (5.9%), respectively.

CONCLUSIONS

Initial therapy consisting of a single session of PDT combined with IVB and STTA improves vision in treatment-naive subfoveal PCV. Compared with double therapy, this triple therapy may be more effective for PCV.

Ranibizumab for the treatment of degenerative ocular conditions

Degenerative ocular conditions, such as age-related macular degeneration, diabetic retinopathy, retinal vein occlusions, and myopic degeneration, have become a major public health problem and a leading cause of blindness in developed countries. Anti-vascular endothelial growth factor (VEGF) drugs seem to be an effective and safe treatment for these conditions. Ranibizumab, a humanized monoclonal antibody antigen-binding fragment, which inhibits all biologically active isoforms of VEGF-A, is still the gold standard treatment for the majority of these pathological entities. In this review, we present the results of the most important clinical trials concerning the efficacy and safety of ranibizumab for the treatment of degenerative ocular conditions.

Elevated Plasma Pentraxin3 Levels and Its Association with Neovascular Age-related Macular Degeneration

PURPOSE

To evaluate pentraxin3 (PTX3) levels in patients with neovascular age-related macular degeneration (N-ARMD) and to investigate its role as a predictive biomarker.

METHODS

Thirty individuals with N-ARMD and 30 controls without N-ARMD were studied. Plasma concentrations of C-reactive protein (CRP) and PTX3 were measured in frozen samples using an enzyme-linked immunosorbent assay kit.

RESULTS

PTX3 concentration was 1341 ± 625 pg/mL (mean ± standard deviation) in N-ARMD patients, which was significantly higher than in control subjects (887 ± 478, p = 0.003). The mean CRP level was also significantly higher in N-ARMD (2121 ± 2300) than in control (748 ± 618, p = 0.004). Pearson's correlation analysis showed a significant positive correlation between PTX3 and CRP (r = 0.407, p = 0.002).

CONCLUSIONS

Our data support the role of chronic inflammation in the development of ARMD. They also show PTX3 may contribute to efforts to understand pathogenesis of N-ARMD.

Polypoidal choroidal vasculopathy: clinical features and genetic predisposition

Polypoidal choroidal vasculopathy (PCV) is currently recognized as a phenotype of age-related macular degeneration (AMD). PCV is believed to be a type of choroidal neovascularization, although some cases of PCV show a distinct vascular abnormality of the choroidal vessels. PCV often shows several unique clinical manifestations which are apparently different from typical neovascular AMD (tAMD). In addition, the natural course and response to treatment are often different between tAMD and PCV. Moreover, recent genetic studies suggested a possible difference in the genetic susceptibility to disease between tAMD and PCV, as well as the existence of heterogeneity among PCV cases. In viewing the accumulation of knowledge about PCV, we have summarized the recent literature regarding PCV in this review article to improve the understanding of this clinical entity including possible susceptibility genes. We will also discuss the optimal treatment strategies for PCV in accordance with the results of recent clinical and genetic studies.

ARMS2 interference leads to decrease of proinflammatory mediators

BACKGROUND

Age-related macular degeneration (AMD) is a major cause of irreversible blindness among elderly people in developed countries. Many studies suggested that age-related maculopathy susceptibility 2 (ARMS2) is the second major susceptibility gene for AMD. Increasing evidence was found recently that inflammatory processes and oxidative stress may contribute to the pathogenesis of AMD. Meanwhile, the mechanisms underlying the contributions of ARMS2 to the pathogenesis of AMD remain unclear. The purpose of the current study was to elucidate the relationship between the ARMS2 gene and proinflammatory mediators, for further assessment of the associated biologic effects.

METHODS

siRNA was used to knock down ARMS2 mRNA, and Western blotting and reverse real-time PCR were used to detect the effect of siRNA on the expression of ARMS2 in ARPE-19 cells. The expressions of C3, C5, IL-6, IL-8, and TNF-α after si-RNA knockdown were evaluated by SYBR Green I real-time PCR and ELISA.

RESULTS

Transcription accumulative indexes (TAI = 2(-delta delta CT)) of ARMS2 by real-time PCR revealed that the transfection rate in the positive control group was 72.0 ± 2.07 % (P < 0.01). The ratio of absorbance values (by Western blotting) of AMRS2 to β-actin was 0.85 ± 0.122, 0.87 ± 0.143, and 0.61 ± 0.240 in the blank control group, scrambled ARMS2-siRNA group, and ARMS2-siRNA group respectively (F = 42.5, P < 0.01). The secreted protein levels of C3, C5, IL-6, IL-8, and TNF-α were found by ELISA to be reduced by 34.24 ± 1.81 %, 37.15 ± 2.02 %, 35.11 ± 1.75 %, 30.11 ± 2.19 %, and 34.33 ± 2.18 % respectively, in the siRNA-ARMS2 group (P < 0.05). Compared with the blank control group, reduced TAI of C3, C5, IL-6, IL-8, and TNF-α were detected by real-time PCR in the ARMS2-siRNA group.

CONCLUSION

This study produced evidence supporting the notion that the ARMS2 risk allele for AMD is linked directly or indirectly to proinflammatory mediators. More importantly, our data indicate that the change in ARMS2 may affect C3, C5, IL-6, IL-8, and TNF-α levels, and this may be one of the mechanisms of AMD development.

The age-related maculopathy susceptibility 2 polymorphism and polypoidal choroidal vasculopathy in Asian populations: a meta-analysis

OBJECTIVE

To assess the role of the age-related maculopathy susceptibility 2 (ARMS2) A69S polymorphism as a risk factor for polypoidal choroidal vasculopathy (PCV) in Asian populations.

METHODS

We performed a meta-analysis of the association of the A69S variant with PCV in Asian populations using data available from 14 case-control studies involving 6552 subjects. Summary odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using fixed- and random-effects models. Sensitivity analysis also was performed.

MAIN OUTCOME MEASURES

Understanding the relationship between the A69S variant and PCV is essential to provide new insights into pathophysiology and potential targets for intervention of PCV.

RESULTS

The pooled OR in random-effects models for genotype TG+TT versus wild homozygous genotype GG is 2.39 (95% CI, 1.98-2.89), the OR of heterozygous genotype TG versus GG is 1.66 (95% CI, 1.37-2.00), the OR of homozygous genotype TT versus GG is 4.74 (95% CI, 3.94-5.70), and the OR of allele T versus G is 2.14 (95% CI, 1.79-2.56). A sensitivity analysis indicated the robustness of our findings.

CONCLUSIONS

Our analysis provides evidence that the A69S variant is associated with an increased risk of PCV in Asian populations. The variant of A69S could be a promising genetic biomarker of PCV.

FINANCIAL DISCLOSURE(S)

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Asian Age-Related Macular Degeneration: Current Concepts and Gaps in Knowledge

Data on the epidemiology and treatment of age-related macular degeneration (AMD) in Asian populations have been scarce. Recently, significant advances in the current knowledge of AMD in Asia have been made, but deficiencies in important areas remain. Epidemiological data on AMD in those 80 years or older are lacking.There are also few incidence data on AMD or polypoidal choroidal vasculopathy (PCV), an important variant of AMD that seems to be more common in Asia. The risk factors for PCV have not been clearly defined to the extent that those for AMD have. No trials of nutritional supplementation for AMD prevention in Asia exist, and there is also a lack of long-term clinical trial data on combination therapy for PCV and indeed very few trial data on PCV. These represent opportunities for future research. With aging populations in Asia, increased data on the prevalence, risk factors, prevention, and treatment of AMD and PCV in Asian populations will be needed to formulate evidence-based public health and clinical guidelines.

Associations of the C2-CFB-RDBP-SKIV2L locus with age-related macular degeneration and polypoidal choroidal vasculopathy

PURPOSE

To investigate the associations of the C2-CFB-RDBP-SKIV2L region with neovascular age-related macular degeneration (AMD) and polypoidal choroidal vasculopathy (PCV).

DESIGN

Cross-sectional, case-control association study.

PARTICIPANTS

A Chinese case-control group of 200 neovascular AMD patients, 233 PCV patients, and 275 control subjects.

METHODS

An association analysis was performed of the C2-CFB-RDBP-SKIV2L locus with both neovascular AMD and PCV in a Chinese population using 19 haplotype-tagging single nucleotide polymorphisms (SNPs) and 6 previously reported SNPs across the C2-CFB-RDBP-SKIV2L region. All SNPs were genotyped using the TaqMan genotyping technology (TaqMan; Applied Biosystems [ABI], Foster City, CA).

MAIN OUTCOME MEASURES

Allele and haplotype frequencies of the SNPs in the C2-CFB-RDBP-SKIV2L region.

RESULTS

The SKIV2L SNPs rs429608 and rs453821 were significantly associated with neovascular AMD (P = 7.39 × 10(-5); odds ratio [OR], 0.22; 95% confidence interval [CI], 0.10-0.50; and P = 0.001; OR, 0.38; 95% CI, 0.21-0.70, respectively), whereas borderline associations were detected for C2 rs547154 (P = 0.002) and RDBP rs760070 (P = 0.003). Conditional haplotype analysis revealed that SKIV2L rs429608 could account fully for the global haplotype association identified in this region. The association of SKIV2L rs429608 with neovascular AMD remained significant after adjusting for CFH rs800292 and HTRA1 rs11200638. No individual SNP or haplotype was associated significantly with PCV.

CONCLUSIONS

In this concurrent investigation of the associations of the entire C2-CFB-RDBP-SKIV2L region with neovascular AMD and PCV, the results suggested that SKIV2L is a likely causal gene for neovascular AMD, conferring a significant protective effect independent of CFH and HTRA1. These data do not support a significant role of this region in PCV, suggesting different molecular mechanisms between neovascular AMD and PCV.

Major single nucleotide polymorphisms in polypoidal choroidal vasculopathy: a comparative analysis between Thai and other Asian populations

PURPOSE

To investigate the association in a Thai population between the major age-related macular degeneration (AMD) susceptibility loci, Y402H and I62V in the complement factor H (CFH) and A69S in the age-related maculopathy susceptibility 2 (ARMS2) genes, and polypoidal choroidal vasculopathy (PCV).

METHODS

A case-control study included 97 PCV cases and 102 age- and gender-matched controls without any retinopathy. The genotypic profiles of the three polymorphisms were obtained using a real-time polymerase chain reaction assay. The allelic and genotypic association between the polymorphisms and PCV were compared with those from the compiled data of other Asian populations reported previously.

RESULTS

Strong associations between the Y402H, I62V, and A69S polymorphisms and PCV were observed in the present study (P = 0.002, 0.003, and 0.0008 respectively) and in the compiled data (P < 0.0001 for all three polymorphisms). The risk allele frequencies of the polymorphisms in PCVs and in controls from the present study (15.0% and 5.4% for Y402H, 71.7% and 57.4% for I62V, and 54.1% and 37.3% for A69S respectively) were also comparable with the frequencies from the compiled data (10.3% and 6.4% for Y402H, 75.2% and 58.3% for I62V, and 56.8% and 36.8% for A69S respectively). The genotype distribution for each polymorphism was also comparable in both datasets.

CONCLUSION

The findings of this study support a significant genetic association between the major AMD susceptibility genes and PCV across Asian populations. This suggests that AMD and PCV, despite different phenotypic manifestation, may share common genetic risk factors.

The role of CRP and inflammation in the pathogenesis of age-related macular degeneration

Age-related macular degeneration (AMD) is a complex, degenerative and progressive disease involving the multiple genetic and environmental factors that can result in severe visual loss. The etiology of AMD is not well understood. Many theories exist and feature mechanisms of oxidative stress, atherosclerotic-like changes, genetic predisposition and inflammation. The most recent clinical studies appointed to a great role of inflammation and C-reactive protein (CRP) in the pathogenesis of AMD. There is a large body of evidence indicating the association of CRP with endothelial dysfunction, oxidative stress and production of reactive oxygen species (ROS), as well as with lipid status disorder in AMD patients. According to recent studies, CRP is definitely not only the inflammatory marker but also a mediator of development of the vascular disorders in the retinal circulation. The results obtained from the present studies may help our understanding the pathogenesis of the retinal vascular disease associated with high levels of CRP.

Natural course and funduscopic findings of polypoidal choroidal vasculopathy in a Japanese population over 1 year of follow-up

PURPOSE

To evaluate the natural course and possible funduscopic risk factors for polypoidal choroidal vasculopathy in a Japanese population.

METHODS

The records of 42 eyes from 41 patients (27 men and 14 women) diagnosed as having polypoidal choroidal vasculopathy located in the macula between November 1999 and October 2005 were retrospectively reviewed. The funduscopic findings at the first visit were evaluated. The changes in the best-corrected visual acuity (BCVA) from the baseline to 12 months were analyzed. The lesion types (clustered vs. nonclustered) found on indocyanine green angiography were compared for changes in the BCVA from the initial visit to 12 months.

RESULTS

The mean age of the subjects was 73.8 ± 8.0 years. The mean logarithm of the minimum angle of resolution (LogMAR) BCVA was 0.48 ± 4.0 at baseline and deteriorated to 0.75 ± 5.7 after 12 months, which was statistically significant (P = 0.00075). The mean LogMAR BCVA in the patients showing "nonclustered" polypoidal choroidal lesions on indocyanine green angiography was maintained for 12 months, while that of the "clustered" group decreased significantly during the same period (P = 0.0014).

CONCLUSION

Polypoidal choroidal vasculopathy did not show a favorable outcome in terms of the mean BCVA 12 months after the initial visit. The clustered polypoidal choroidal lesions on indocyanine green angiography may be related to poor prognosis of polypoidal choroidal vasculopathy over the natural course.

Genetic variants in pigment epithelium-derived factor influence response of polypoidal choroidal vasculopathy to photodynamic therapy

PURPOSE

To investigate whether photodynamic therapy (PDT) outcomes of polypoidal choroidal vasculopathy (PCV) are related to baseline clinical characteristics, smoking history, or genetic factors by analyzing the retreatment-free period after the first PDT.

DESIGN

Retrospective cohort study.

PARTICIPANTS

The study consisted of 167 patients with PCV who underwent PDT as their first treatment.

METHODS

We targeted 638 single nucleotide polymorphisms (SNPs) in 42 possible susceptible genes for age-related macular degeneration to evaluate their relation to the effectiveness of PDT for PCV. For this evaluation, we used 2 methods: (1) survival analysis, with the retreatment-free period as the target; and (2) logistic regression test between the need for additional therapy within 3 months after the first PDT and the genotypes, with age, gender, smoking status, and greatest linear dimension (GLD) at baseline as covariates. The contributions of smoking status and GLD at baseline for the retreatment-free period also were evaluated. Contributions of these factors to visual prognosis were evaluated for 1 year after PDT.

MAIN OUTCOME MEASURES

Retreatment-free period after the first PDT for PCV. Secondary outcome measures included correlation of the susceptible factor to the retreatment requirement within the 3-month follow-up and the mean visual acuity change.

RESULTS

In survival analyses, SERPINF1 rs12603825 showed a significant association with the retreatment-free period after the first PDT; those patients homozygous for the minor allele A of rs12603825 received additional treatment after PDT within significantly shorter times than those with other genotypes (P = 0.0038). There was no significant difference in the retreatment-free period between baseline GLD and smoking status. Retreatment within 3 months was required significantly more in patients with the AA genotype, even after taking into consideration the effect of clinical characteristics (age, gender), baseline PCV lesion size, and smoking status (P = 0.0027). Furthermore, patients with the AA genotype showed significantly worse visual prognosis after PDT (P = 0.013).

CONCLUSIONS

Pigment epithelium-derived factor (SERPINF1 or PEDF) polymorphisms may influence the initial response to and visual prognosis after PDT for PCV. Our findings may lead to understanding the pathogenesis of PCV and modification of the effects of PDT.

A review and meta-analysis of the association between C-reactive protein and age-related macular degeneration

Age-related macular degeneration (AMD) is the leading cause of blindness in people over 60 in western countries. Inflammatory markers have been implicated in the development and progression of AMD. C-reactive protein (CRP) is an inflammatory marker known to be associated with cardiovascular disease, and a link between AMD and CRP has been suggested. In this systematic review we summarize the currently available evidence from clinic-based and population-based studies investigating this association. A meta-analysis of evidence from eleven studies (41,690 study participants) shows that high serum levels (>3 mg/L) of CRP are associated with a two-fold likelihood of late onset AMD, compared to low levels (<1mg/L). Sub-group meta-analyses show a higher association in studies using ophthalmoscopic examination, compared to those using photographic grading (pooled odds ratio 3.83 vs 1.36), to determine AMD status, or in clinic-based samples compared to population-based studies.

The association of lipoprotein parameters and C-reactive protein in patients with age-related macular degeneration

BACKGROUND

Age-related macular degeneration (AMD) is the most common cause of visual impairment in individuals over 50 years of age, with the prevalence of 0.05% before the age of 50 rising to 30% after 74 years of age. An elevated concentration of plasma lipoproteins is considered to be one of the risk factors of AMD development. The aim of our study was to analyze the concentration of serum lipoproteins - total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL), non-LDL cholesterol and triglycerides - as well as apolipoproteins - apoA1, apoB and Lp(a) - along with C-reactive protein (CRP) in patients with AMD in order to explore the possible association of lipid and inflammatory parameters with the pathogenesis of AMD.

MATERIAL AND METHODS

In the cross-sectional study in the University clinical setting, 79 patients with AMD, aged 71.47 ± 7.02 years, and 84 aged-matched control subjects were included. The patients underwent complete ophthalmological examination including visual acuity assessment, color fundus photography and fluorescein angiography.

RESULTS

Statistical processing data revealed significantly higher total (p = 0.0002), LDL (p = 0.023), non-HDL cholesterol (p = 0.0014) and CRP (p = 0.049) values in AMD patients compared to control subjects.

CONCLUSIONS

Based on the obtained results, it may be concluded that lipid status disorder and inflammation could play an important role in the development of AMD in elderly people.

Retinal pigment epithelial cells upregulate expression of complement factors after co-culture with activated T cells

In this study we examined the effect of T cell-derived cytokines on retinal pigment epithelial (RPE) cells with respect to expression of complement components. We used an in vitro co-culture system in which CD3/CD28-activated human T cells were separated from the human RPE cell line (ARPE-19) by a membrane. Differential gene expression in the RPE cells of complement factor genes was identified using gene arrays, and selected gene transcripts were validated by q-RT-PCR. Protein expression was determined by ELISA and immunoblotting. Co-culture with activated T cells increased RPE mRNA and/or protein expression of complement components C3, factors B, H, H-like 1, CD46, CD55, CD59, and clusterin, in a dose-dependent manner. Soluble factors derived from activated T cells are capable of increasing expression of complement components in RPE cells. This is important for the further understanding of inflammatory ocular diseases such as uveitis and age-related macular degeneration.

Relationship of smoking and cardiovascular risk factors with polypoidal choroidal vasculopathy and age-related macular degeneration in Chinese persons

PURPOSE

Polypoidal choroidal vasculopathy (PCV) has been described as a distinct clinical entity from choroidal neovascularization (CNV) secondary to age-related macular degeneration (AMD). The present study aimed to determine risk factors for PCV and to compare associations with those for CNV secondary to AMD.

DESIGN

Case-control study.

PARTICIPANTS

Patients of Chinese ethnicity with clinically and angiographically diagnosed PCV (n = 123) or CNV secondary to AMD (n = 128) were recruited from a tertiary eye hospital in Singapore. Controls without signs of PCV, CNV secondary to AMD, or other retinal pathologic features (n = 1489) were selected from a population-based study.

METHODS

Patients underwent an ophthalmologic examination including digital color fundus photography, stereoscopic fluorescein angiography (FA), and indocyanine green angiography (ICGA). Classification into PCV or CNV secondary to AMD was based on FA and ICGA findings. Risk factors were determined from a standardized interview, with blood pressure recorded using a digital automatic blood pressure monitor.

MAIN OUTCOME MEASURES

Polypoidal choroidal vasculopathy or CNV secondary to AMD.

RESULTS

Persons who smoked were more likely to have PCV (39.9% vs. 13.4%) or CNV secondary to AMD (45.0% vs. 12.3%) than those who did not smoke. After controlling for age, gender, diabetes, hypercholesterolemia, and hypertension, persons who smoked were 4 times more likely to have PCV (odds ratio [OR], 4.4; 95% confidence interval [CI], 2.5-7.7; P<0.001) and CNV secondary to AMD (OR, 4.9; 95% CI, 2.7-8.8; P<0.001). A significant, negative association also was found between diastolic blood pressure and CNV secondary to AMD (OR, 0.7; 95% CI, 0.5-0.9; P = 0.017, adjusted for age, gender, smoking, diabetes, and hypercholesterolemia), but diastolic blood pressure was not associated with PCV.

CONCLUSIONS

Smoking but not other vascular risk factors is significantly associated with both PCV and CNV secondary to AMD in Chinese persons. The similarity of associations suggests that there may be common risk factors and pathological mechanisms.

Polypoidal choroidal vasculopathy: a review

More than a quarter century has passed since the original description of polypoidal choroidal vasculopathy (PCV) in 1982 as a peculiar hemorrhagic disorder involving the macula characterized by recurrent subretinal pigment epithelial bleeding. In the ensuing years, numerous reports have described the expanded clinical spectrum of this entity. PCV is the principal vascular composition of patients of pigmented races experiencing neovascular maculopathies, particularly African Americans and Asians. This form of neovascularization is now known to occur in white patients with or without concomitant drusen, and the site of involvement has extended from the peripapillary area to the peripheral fundus. Indocyanine green angiography has made detection of these abnormal vascular changes more reliable and definitive. More precise diagnosis has also led to a better understanding of specific clinical features that distinguish PCV from more typical proliferations of abnormal choroidal vessels. We review the nature of PCV, including its genetic basis, demographic features, histopathology, clinical manifestations, natural course, response to treatments, and the histopathological and genetic bases. We emphasize multimodal ophthalmic imaging of these vessels, in particular fluorescein and indocyanine green angiography and optical coherence tomography.

Three major loci involved in age-related macular degeneration are also associated with polypoidal choroidal vasculopathy

PURPOSE

To investigate the frequency of variants in 3 major age-related macular degeneration (AMD)-associated loci in patients of European-American descent with polypoidal choroidal vasculopathy (PCV).

DESIGN

Cross-sectional, case-control association study.

PARTICIPANTS

Fifty-five patients with PCV, 368 patients with advanced AMD, and 368 age-matched and ethnically matched unaffected controls of European-American descent.

METHODS

Association analysis of allele and genotype frequencies, determined by TaqMan assays, was performed for the following haplotype-tagging single nucleotide polymorphisms (htSNPs): risk alleles in the complement factor H (CFH) gene (Y402H and IVS14) in the ARMS2/HTRA1 locus on 10q26 (A69S) and protective alleles in CFH (IVS1 and IVS6) and in the complement factor B/complement component C2 (CFB/C2) locus (IVS10 and H9L).

MAIN OUTCOME MEASURES

Allele and genotype frequencies of the htSNPs in the CFH, CFB/C2, and ARMS2/HTRA1 loci.

RESULTS

Four AMD-associated haplotype-tagging alleles (rs547154, rs1061170, rs1410996, rs10490924) in the 3 major loci, CFH, CFB/C2, and ARMS2/HTRA1, also were statistically significantly associated with the PCV phenotype (P<0.05). Three other alleles from the same loci (rs4151667, rs529825, rs3766404) showed a trend toward association (P<0.2) but did not reach statistical significance, possibly because of the combined effects of a relatively small sample size and low minor allele frequency in the screened populations.

CONCLUSIONS

The PCV phenotype in Caucasian patients is associated with the major alleles/genotypes in the AMD-associated loci, suggesting that PCV and AMD are genetically similar in the tested loci.

Monozygotic twins with polypoidal choroidal vasuculopathy

Purpose:

To present the first findings in the set of monozygotic twins with polypoidal choroidopathy (PCV).

Methods:

Sixty two-year old monozygotic twin sisters were studied. The concordances and discordances of the clinical features of the twins were determined. Genomic DNA was extracted and genotyped for three established PCV risk-associated single nucleotide polymorphisms, viz CFH I62V, CFH Y402H, and ARMS A69S.

Results:

Both patients had hemorrhagic pigment epithelial detachments with orange lesions beneath the retinal pigment epithelium. Indocyanine green angiography showed pathognomonic choroidal vascular networks with polypoidal structures uniocularly in one twin and binocularly in the other twin. Both twins were treated with photodynamic therapy, retinal photocoagulation, and anti-vascular endothelial growth factor therapy, but both showed limited response to all the treatments, with recurrent exudative lesions with enlarged vascular network, and poor visual outcome. Genetic analyses showed that both sisters had homozygous risk alleles for ARMS2 A69S, and one risk allele each of CFH I62V and CFH Y402H.

Conclusions:

We present the first findings in a set of monozygotic twins with typical PCV under long-term observation. The concordances in disease progression and response to treatment between the twins indicate that these genetic factors most likely played important roles in determining the clinical manifestations.

C-reactive protein levels and complement factor H polymorphism interaction in age-related macular degeneration and its progression

PURPOSE

To determine the effect of elevated level of C-reactive protein (CRP) and its joint effect with the complement factor H (CFH) polymorphism on prevalent age-related macular degeneration (AMD) and its progression.

DESIGN

Two-arm case-control study: (a) Study on prevalent AMD cases and population-based controls; (b) longitudinal study on AMD progression, comparing those in whom AMD progressed with those with no progression.

PARTICIPANTS

(a) A cross-sectional sample of 544 participants, of whom 312 had features of early or late AMD and 232 were controls; (b) a sample of 254 early AMD cases, followed for 7 years.

METHODS

The study was conducted in Melbourne, Australia. Macular stereo photographs were graded for AMD according to the International Classification and Grading System. High-sensitivity CRP was measured in fresh serum, and genotyping was performed through the Australian Genome Research Facility. The association of CRP with outcomes was tested using multivariate logistic regression analysis adjusted for age, smoking, anti-inflammatory medications, and the CC genotype of the CFH gene. Risk factor interaction was explored using an additive model.

MAIN OUTCOME MEASURES

Prevalent early AMD, prevalent late AMD, progressed AMD, and measures of risk factor interaction.

RESULTS

Elevated CRP levels were associated with late AMD: odds ratio (OR), 3.12; 95% confidence interval (CI), 1.38-7.07. An association of elevated CRP with AMD progression was weaker: OR, 1.90 (95% CI, 0.88-4.10). A combination of elevated CRP and the CC (Y402H) genotype resulted in a super-additivity of the risks, with odds ratios of 19.3 (95% CI, 2.8-134) for late AMD, and 6.8 (95% CI, 1.2-38.8) for AMD progression, with the attributable proportion of risk owing to CRP-CFH interaction calculated at 26% for prevalent late AMD and 22% for AMD progression.

CONCLUSIONS

Synergistic influence of CRP levels and the at risk genotype of the CFH gene resulted in a super-additive risk for prevalent late AMD and AMD progression. Testing for the combination of these 2 risk factors to predict a high risk of AMD and its progression would allow for targeted trials of new intervention strategies.

Inflammatory choroidal neovascular membrane in posterior uveitis-pathogenesis and treatment

Choroidal neovascular membrane (CNVM) formation is a well-documented sight-threatening complication of posterior segment intraocular inflammation (PSII). The aim of this article is to review the basic and clinical science literature on the pathogenesis of CNVM formation in PSII and to present results of a case series. We searched the literature using the mesh terms- inflammation, CNVM, age-related macular degeneration, immunosuppression, photodynamic therapy, steroids, vascular endothelial growth factors and posterior uveitis. Additionally, we evaluated the visual outcome of and clinical response to our standard treatment protocol involving a combination treatment for young patients with inflammatory CNVM. The development of CNVM in PSII is promulgated by infiltrating myeloid cells as well as choroidal and retinal myeloid cell activation, subsequent vascular endothelial growth factors, cytokine and chemokine production and complement activation acting in consort to mediate angiogenic responses. No clear standard of care currently exists for the treatment of inflammatory CNVM and various combinations have been tried. Using our combination treatment, visual acuity improved in four, stabilized in one and worsened in four patients. Though significant advances have occurred in the understanding of the pathogenesis and management of this condition, optimizing therapeutic regimens will require further well-constructed prospective cohort series.

Induction of interleukin-8 gene expression and protein secretion by C-reactive protein in ARPE-19 cells

C-reactive protein (CRP) is an acute phase reactant and its level rises rapidly during inflammation. Recent studies have suggested the potential involvement of CRP in the pathogenesis of age-related macular degeneration (AMD). To delineate the functional roles of CRP in inflammatory response by the ocular posterior segments, the effects of CRP on ARPE-19, an immortalized human retinal pigment epithelia (hRPE) cell line, were investigated in the present study. Treatment of ARPE-19 cells with CRP resulted in enhanced NF-kB nuclear translocation and dose-dependent transient induction of IL-8 mRNA synthesis and protein secretion. Stimulated expression of VEGF, but not MCP-1 by CRP was also observed. The induced IL-8 expression was transient and peaked at 12h post stimulation. In the presence of inhibitors for NF-kB, p38, MEK and JNK, the CRP-induced IL-8 production was abolished by 99.5+/-2.3, 97.8+/-2.1, 55.3+/-2.5 and 37.3+/-1.3%, respectively. Neutralization of Fc gamma receptors by anti-CD32 and CD64 antibodies produced 39.9+/-1.6 and 59.5+/-2.6% reduction, respectively, of CRP-stimulated IL-8 secretion, whereas that by anti-CD16 antibody had no effect. This study suggests that the pro-inflammatory effects of CRP in ARPE-19 cells may contribute to the inflammatory retinal diseases by induction of pro-inflammatory cytokines such as IL-8. This induction is mediated by NF-kB and multiple MAPK pathways through Fc gamma receptors.

Role of RDBP and SKIV2L variants in the major histocompatibility complex class III region in polypoidal choroidal vasculopathy etiology

PURPOSE

To investigate whether polymorphisms in 4 tightly linked genes of the major histocompatibility complex class III--complement component 2 (C2), complement factor B (CFB), RD RNA-binding protein (RDBP), and superkiller viralicidic activity 2-like (SKIV2L)--are associated with polypoidal choroidal vasculopathy (PCV).

DESIGN

Cross-sectional study.

PARTICIPANTS

A case-control group of 136 PCV subjects and 183 unrelated controls.

METHODS

We performed an association analysis between PCV and polymorphisms across the C2-CFB-RDBP-SKIV2L region in a Japanese population, genotyping 13 single nucleotide polymorphisms (SNPs) spanning this region, including rs9332739 (E318D), rs547154, rs4151667 (L9H), and rs641153 (R32Q) that are known to be associated with age-related macular degeneration (AMD). Genotyping was conducted using TaqMan technology (Applied Biosystems, Foster City, CA). We also examined population stratification in our study cohort.

MAIN OUTCOME MEASURES

Allele and haplotype frequencies of the variants across the C2-CFB-RDBP-SKIV2L region.

RESULTS

We initially scanned the C2-CFB locus using 11 SNPs that capture the majority of common variations in this locus. We found a significant omnibus haplotype association and a single disease-protective haplotype, but individually, none of the 11 SNPs were associated with PCV. Further studies led to the identification of 2 untested allelic variants in RDBP (rs3880457) and SKIV2L (rs2075702) that were located on the protective haplotype. We also analyzed these 2 SNPs, detecting a significant association with a decreased risk of developing PCV (for both SNPs, allelic P = 0.0038 and per allele odds ratio = 0.31 [95% confidence interval, 0.13-0.71]). The 2 SNPs were correlated (r(2) = 1) in our dataset. Haplotype analysis and conditional testing demonstrated that either rs3880457 or rs2075702 could fully account for the omnibus haplotype association detected across the C2-CFB-RDBP-SKIV2L region. Population stratification analyses excluded stratification artifacts in our study cohort.

CONCLUSIONS

Our results do not support any major role of the 4 AMD-associated variants in the risk of developing PCV, but favor a predominant association with the RDBP-SKIV2L variants, which has some potential implications for pathobiological differences between PCV and neovascular AMD. Further genetic characterization of this locus will provide additional insights into the genetic basis of PCV susceptibility.

[Polypoidal choroidal vasculopathy: clinical and angiographic features]

OBJECTIVES

To clarify the clinical and angiographic characteristics of idiopathic polypoidal choroidal vasculopathy (IPCV) and its natural course.

METHODS

Descriptive, prospective, consecutive case series of patients with presumed IPCV seen at Fort-de-France Hospital Center (French West Indies) between January and June 2006. All participants underwent complete eye examination and fluorescein and indocyanine green (ICG) angiography. The nature and location of the lesions were assessed in all eyes. Inclusion criteria were demonstration of characteristic lesions of IPCV on ICG angiography.

RESULTS

Diagnosis of IPCV was made in 26 eyes of 14 patients, ten women and four men, all of Afro-Caribbean origin. The mean age was 77.4 years (range 60-92 years). Drusen were present in 13 eyes (50%), age-related macular degeneration (AMD) in one eye, and branch retinal vein occlusion in one eye. Twelve patients (85.7%) had bilateral involvement. Twelve eyes (46.2%) had visual acuity (VA) (Snellen) worse than 20/200, six eyes (23.1%) had VA between 20/200 and 20/100, and eight eyes (30.8%) had VA better than 20/100. On ICG angiography, lesions were predominantly located in the peripapillary area but also in the midperiphery, the macular and interpapillomacular areas, and the far periphery.

CONCLUSION

Peripheral locations of IPCV and associations with drusen or AMD are not rare. The prognosis of the disease is poor in its natural course. Its etiology is unknown but genetic factors are probably involved. It is the main differential diagnosis for exudative AMD in black patients.

Two-year results of photodynamic therapy for polypoidal choroidal vasculopathy

PURPOSE

To report on the two-year visual outcomes of indocyanine green angiography-guided photodynamic therapy (PDT) for polypoidal choroidal vasculopathy (PCV) patients.

DESIGN

Retrospective case study.

METHODS

A retrospective analysis that examined the clinical and angiographic data related to 41 eyes of 38 PCV patients (25 males, 13 females; average age +/- standard deviation [SD], 72.9 +/- 7.4 years) with follow-up periods of 24 months or more.

RESULTS

The average number of PDT treatments was 1.65. After the 12-month follow-up, 12 eyes required retreatment. Although the mean visual acuity (VA) +/- SD before PDT (0.55 +/- 0.38 logarithm of the minimum angle of resolution units) improved to 0.46 +/- 0.41 at 12 months after the initial PDT, at 24 months, it declined significantly to 0.59 +/- 0.44 (P = .0018). Although only seven of 41 eyes exhibited VA deterioration at the 12-month follow-up examination, a decreased VA was noted in 18 eyes during the period starting from the 12-month follow-up until the final examination. The cases were bilateral in 11 (61.1%) of the 18 eyes. At the final examination, the mean VA of the bilateral cases but not the unilateral cases was significantly lower than that observed for the initial VA.

CONCLUSIONS

PDT is an effective treatment against PCV over the short-term for both unilateral and bilateral cases. However, the VA prognosis may not the same after 12 months, especially for those PCV patients who have exudative age-related macular degeneration in contralateral eye.