Les facteurs de risque du glaucome primitif à angle ouvert

Prevalence of Glu323Lys Mutation of the TIGR/MYOC Gene and Risk Factors amongst Primary Open-angle Glaucoma Patients in Ouagadougou, Burkina Faso

Aim

Glaucoma is a group of degenerative diseases of the optic nerve whose predisposing factors may be genetic. The objective of this study was to estimate the frequency of the Glu323Lys mutation as a genetic risk factor for glaucoma.

Materials and methods

A cross-sectional study over 6 months from October 2020 to March 2021 in Ouagadougou, Burkina Faso. A total of 89 samples of patients with primary open-angle glaucoma (POAG) were collected. The frequency of the Glu323Lys mutation of the myocilin, trabecular meshwork inducible glucocorticoid response (TIGR/MYOC) gene by polymerase chain reaction (PCR)-restriction fragment length polymorphism.

Results

In glaucoma patients, only homozygous nonmutated guanine-guanine (GG) and heterozygous mutated adenine-guanine (AG) genotypes were found in 96.63 and 3.37% of cases, respectively. Around 69.66% of patients had a family history of glaucoma, 28.09% had a history of hypertension, and 7.86% had a history of diabetes.

Conclusion

The frequency of the Glu323Lys mutation of the TIGR/MYOC gene was 3.37% in the glaucoma population in Ouagadougou. A case-control study is necessary to know the contribution of the Glu323Lys mutation as a genetic risk factor for glaucoma in our study population.

Clinical significance

This study constituted the beginning of genetic investigations of glaucoma in our context and showed a low Glu323Lys mutation.

How to cite this article

Traoré L, Sanou J, Bakyono BS, et al. Prevalence of Glu323Lys Mutation of the TIGR/MYOC Gene and Risk Factors amongst Primary Open-angle Glaucoma Patients in Ouagadougou, Burkina Faso. J Curr Glaucoma Pract 2023;17(2):79-84.

Gelatin implant in the treatment of open-angle glaucoma: Safety and efficacy in real-life conditions

OBJECTIVE

To evaluate the safety and efficacy of the Xen® implant for the treatment of open-angle glaucoma.

MATERIAL AND METHOD

Retrospective study including patients who received the Xen® implant between January 2019 and December 2020 in a university hospital. Demographic and medical data were collected using DxCare® software. The primary endpoint was a 20% reduction in intraocular pressure (IOP) at 12 months according to Société Française du Glaucome (SFG) recommendations. The secondary endpoints were decrease in glaucoma medications and incidence of adverse events.

RESULTS

Fifty-three patients (65 eyes) were included (sex ratio 0.65, age 75.38±7.31 years). IOP decreased by 18.51% from 17.86±4.22mmHg to 14.55±2.66mmHg (P<0.05). The number of glaucoma medications was 2.16±1.01 preoperatively vs 0.49±0.94 postoperatively (P<0.05). Adverse events included 8 malpositionings, 3 of which required reoperation, 1 case of increased IOP resolved by trabeculectomy, 1 case of venous ischemia treated by photocoagulation, 3 choroidal detachments and 3 corneal ulcers. Needling was required for 18 eyes.

CONCLUSION

At 12 months, the IOP was lower than previously reported in the literature (14.55 vs 15.90mmHg, P<0.05), probably due to a lower preoperative IOP. The number of postoperative medications was similar to the literature (0.49 vs 0.40, P=0.51), as was the frequency of needling (27.69% vs 32.00%, P=0.36). The frequency of malpositioning was higher (12.31% vs 7.70%, P<0.05), probably due to the management of complicated patients. The efficacy of Xen® was in line with recommendations. It would be interesting to compare the efficacy of Xen® with trabeculectomy.

Risk Factors for Primary Open Angle Glaucoma (POAG) Progression: A Study Ruled in Torino

Purpose:

Aim of this retrospective, observational study is to describe features of a population sample, affected by primary open angle glaucoma (POAG) in order to evaluate damage progression on the basis of the emerged individual risk factors.

Methods:

We included 190 caucasian patients (377 eyes), evaluating relationship between individual risk factors (explicative variables) and MD (Mean Deviation) of standard automated perimetry. We also considered the dependent variable NFI (Neural Fiber Index) of GDx scanning laser polarimetry. Progression has been evaluated through a statistic General Linear Model on four follow up steps (mean follow up 79 months).

Results:

Factors reaching statistical significance, determining a worsening of the MD variable, are: age (P<0.0001), intraocular pressure (IOP) at follow up (P < 0.0001), female gender (P<0.0001), hypertension (P< 0.0001) and familiarity (P = 0.0006).

Factors reaching statistical significance, determining a worsening of the NFI variable, are only IOP at follow up (P = 0.0159) and depression (P = 0.0104).

Conclusion:

Results of this study confirm and enforce data coming from most recent studies: IOP remains the main risk factor for glaucoma assess and progression; age and familiarity are great risk factors as underlined in the last decades; female sex can be an important risk factors as emerged only in the last years; arterial hypertension should always be evaluated in timing of our clinic follow up.

Identification of a novel MYOC mutation in a Chinese family with primary open-angle glaucoma

PURPOSE

The myocilin (MYOC) gene has been shown to be related to primary open-angle glaucoma (POAG). This study was aimed to detect the mutations in MYOC in a Chinese family with POAG.

METHODS

A family with four members, the parents, a son and a daughter, was enrolled in this study. All members of the family underwent the complete ophthalmologic examinations. Genomic DNA was collected from peripheral blood of all the participants. The coding sequence of MYOC was amplified by polymerase chain reaction (PCR), followed by direct DNA sequencing.

RESULTS

The son, who was the proband of this family, was diagnosed as early-onset POAG in both eyes. His mother was diagnosed as POAG ten years ago. A novel heterozygous missense mutation c.761C<G (p.P254R) in the MYOC gene, was identified as being co-segregated with the phenotype of this family. This mutation was detected in the two affected patients, but not present in the other normal family members or 384 normal controls.

CONCLUSIONS

This study provides a mutation spectrum of MYOC resulting in POAG development in a Chinese population, which may help to better understand the molecular pathogenesis and clinical diagnosis of MYOC-associated POAG.

Association of SOD2 polymorphisms with primary open angle glaucoma in a Chinese population

BACKGROUND

Genetic factors have been studied extensively for their role in the pathogenesis of primary open angle glaucoma (POAG). This study was conducted to investigate whether manganese superoxide dismutase (SOD2) variants play a significant role in POAG in a Chinese population.

METHODS

This study included of 416 unrelated POAG patients and 997 unrelated control subjects. Four SOD2 tag single nucleotide polymorphisms (SNPs), including rs6917589 rs2842980, rs5746136 and rs4880, were genotyped by dye terminator-based SNaPshot method. The genotype and allele frequencies were evaluated using the χ(2) tests.

RESULTS

Allelic association analysis showed that there were suggestive differences in the allelic distributions between POAG cases and controls for SNPs rs6917589 and rs5746136 (p = 0.0.046 and p = 0.032, respectively), but no statistically significant association was detected between the two SNPs and POAG after Bonferroni correction (p > 0.0125). The allele and genotype frequency in SNPs rs2842980 and rs4880 showed no statistically significant difference between POAG cases and controls (p = 0.128 and p = 0.867, respectively). SNP rs5746136 had a significant association with POAG in the recessive model (p = 0.003155). Haplotype ATGT generated from the four SNPs showed a trend of association with POAG (p = 0.0098).

CONCLUSION

Our results showed a trend of association with POAG, suggesting that SOD2 may play a significant role in the development of POAG in the Chinese population. Further work with a larger sample size and functional study is needed to confirm the importance of the SOD2 gene in the pathogenesis of glaucoma.

Ocular surface alterations and topical antiglaucomatous therapy: a review

Ocular Surface Disease (OSD) is prevalent among medically treated patients with glaucoma. This is basically related to three key-points: OSD and glaucoma are both prevalent in elderly and are common comorbidities in the same patient; the role of the active ingredient of the medical antiglaucomatous therapy; the role of the preservative agent of this medical therapy.

Considering the actual state of literature we can state that the active glaucoma agent have a role in OSD, but the main cause seems to be the preservative agent, in particular referring to benzalkonium chloride, BAK.

In the clinical evaluation of dry eye patients there is no actually established gold standard. Since the ocular surface injury not only causes dry eye, red eye, eye itching, photophobia and other discomforts, but also increases the risk of failure of glaucoma surgery in patients, it becomes fundamental a complete and good clinical evaluation of OSD (considering Schirmer’s test, tear breakup time, corneal and conjunctival staining) together with a good evaluation of patients’ quality of life (with validated questionnaires).

Development of complex preparations, preservative-free and/or novel preservative preparations for glaucoma therapy could provide a promising approach in the prevention of ocular surface injuries.

Association between helicobacter pylori infection and primary open angle glaucoma

Aim:

To compare the prevalence of Pylori infection in patients with primary open angle glaucoma (POAG) and control group with cataract.

Methods:

This is a prospective case-control study. The participants were organized in two groups. First group (case) consisted of 35 patients with POAG and second group consisted of 35 age matched participants with cataract whose optic disk could be evaluated. Serum levels of anti H. pylori IgG antibody were evaluated with the method of ELISA.

Results:

The seroprevalence of Pylori infection was 89.1 % (33 of 37) in patients with POAG and 59.5 % (25 of 42) in the control group. The difference was significant (P=0.008). The odds ratio for association between Pylori and POAG was 5.69 and the range of 95% confidence interval was from 1.58 to 20.50.

Conclusion:

This study suggests that Helicobacter Pylori infection might be associated with primary open angle glaucoma.

Association of OPA1 polymorphisms with NTG and HTG: a meta-analysis

BACKGROUND

Genetic polymorphisms of the Optic atrophy 1 gene have been implicated in altering the risk of primary open angle glaucoma (POAG), especially the susceptibility to normal tension glaucoma (NTG), but the results remain controversial.

METHODS

Multiple electronic databases (up to January 20, 2012) were searched independently by two investigators. A meta-analysis was performed on the association between Optic atrophy 1 polymorphisms (rs 166850 and rs 10451941) and normal tension glaucoma (NTG)/high tension glaucoma (HTG). Summary odds ratios (ORs) and 95% confidence intervals (CI) were estimated.

RESULTS

Seven studies of 713 cases and 964 controls for NTG and five studies of 1200 cases and 971 controls for HTG on IVS8+4C>T (rs 166850) and IVS8+32T>C (rs10451941) were identified. There were significant associations between the OPA1 rs10451941polymorphism and NTG susceptibility for all genetic models(C vs. T OR = 1.26, 95% CI 1.09-1.47, p = 0.002; CC vs. TT: OR = 1.52, 95% CI 1.04-2.20, p = 0.029; CC vs. CT+TT: OR = 1.64, 95% CI 1.16-2.33, p = 0.005; CC+CT vs. TT: OR = 1.21, 95% CI 1.02-1.44, p = 0.032). However, no evidence of associations was detected between the OPA1 IVS8+32C>T polymorphism and POAG susceptibility to HTG. Similarly, clear associations between the rs 166850 variant and NTG were observed in allelic and dominant models (T vs. C OR = 1.52, 95% CI 1.16-1.99, p = 0.002; TT+TC vs. CC OR = 1.50, 95% CI 1.13-2.01, p = 0.006) but not to HTG. In subgroup analyses by ethnicity, we detected an association between both OPA1 polymorphisms and risk for NTG in Caucasians but not in Asians. By contrast, no significant findings were noted between OPA1 variants for HTG, either in Caucasians or in Asians.

CONCLUSIONS

Both the IVS8+4C>T and IVS8+32T>C variants may affect individual susceptibility to NTG. Moreover, stratified analyses for NTG detecting the effects of both OPA1 polymorphisms seemed to vary with ethnicity. Further investigations are needed to validate the association.

Evaluation of compliance with the EGS guidelines in Spain, using Achievable Benchmarks of Care (ABC®) methodology: the IMCA Study

PURPOSE

To evaluate compliance with diagnostic and therapeutic recommendations of the European Glaucoma Society (EGS) for the management of glaucoma in Spain, as determined using the Achievable Benchmarks of Care approach.

METHODS

A panel of 3 experts extracted quality and process-of-care indicators from the EGS guidelines. Investigators from all over the country, representative of Spanish ophthalmologists, were invited to participate in the study, completing a questionnaire on quality indicators (pertaining to the center) and process-of-care indicators (pertaining to all patients) for the first, diagnostic visit (retrospective) and the study visit.

RESULTS

A total of 495 Spanish ophthalmologists included 5,060 patients with glaucoma or intraocular hypertension. The treatment was initiated with monotherapy in 88.5% of the patients. Overall, the percentage compliance with diagnostic examinations was 84.6% for intraocular pressure measurement, 96.3% for optic nerve head evaluation, 76.6% for visual field evaluation, 29.5% for central corneal thickness evaluation, and 49.3% at the study visit. The benchmark performance was close to 100% for most examinations. Only 32.8% of the centres had a written protocol for the management of the patients with glaucoma, and in these centers the recommendations of the EGS were followed in a higher proportion (p<0.0001) than in the rest.

CONCLUSIONS

The use of local protocols for the management of glaucoma seems to enhance compliance. Benchmark performance was close to 100% in most indicators, suggesting that EGS recommendations are attainable in Spain. The overall performance suggests that certain diagnostic procedures are, in practice, not as widely used as recommended.

Trumpet tension

The case of a 78-year-old man with progressive glaucoma despite seemingly adequate control of his intraocular eye pressure is presented. On further questioning he was discovered to have played the trumpet for up to 4 h per day for 60 years. Significant increases in intraocular pressure were subsequently recorded during trumpet playing.