Consanguinity and its association with visual impairment in southern India: the Pavagada Pediatric Eye Disease Study 2

Burden and clinical profile of genetic eye diseases in children in Nigeria: a descriptive cross-sectional study

Introduction

ophthalmic genetics is rapidly evolving globally but is still nascent in much of sub-Saharan Africa, with gaps in knowledge about the burden in the region. This study evaluated the burden and manifestations of genetic eye diseases in children in Ibadan, Nigeria.

Methods

this was a hospital-based cross-sectional study in which new and follow-up paediatric eye clinic patients were recruited consecutively at the University College Hospital, Ibadan. Children with genetic eye diseases had comprehensive ocular and systemic examinations, and their pedigrees were charted to determine the probable modes of inheritance. The main outcome variables were the proportion of study participants with genetic eye diseases, the probable modes of inheritance, and the clinical diagnoses. Summary statistics were performed using means and standard deviations for numerical variables and proportions for categorical variables.

Results

fifty-two (12%) of 444 children had genetic eye diseases, and their mean (SD) age was 88.8 ± 50.4 months. Thirteen different phenotypic diagnoses were made following the evaluation of the 52 children, including primary congenital glaucoma (13, 25%) and familial non-syndromic cataracts (8, 15%). The probable modes of inheritance were derived from the pedigree charts, and 30 (58%) conditions were presumed to be sporadic.

Conclusion

this study demonstrated a significant burden and a wide range of paediatric genetic eye diseases in this tertiary referral centre in Nigeria. This information provides invaluable evidence for planning ophthalmic genetic services.

Retinitis pigmentosa in Usher syndrome in India: Electronic medical records driven big data analytics: Report III

Purpose:

To describe the clinical presentation and demographic distribution of retinitis pigmentosa (RP) in patients with Usher syndrome (USH).

Methods:

This is a cross-sectional observational hospital-based study including patients presenting between March 2012 and October 2020. In total, 401 patients with a clinical diagnosis of USH and RP in at least one eye were included as cases. The data were retrieved from the electronic medical record database. For better analysis, all 401 patients were reclassified into three subtypes (type 1, type 2, and type 3) based on the USH criteria.

Results:

In total, there were 401 patients with USH and RP, with a hospital-based prevalence rate of 0.02% or 2/10,000 population. Further, 353/401 patients were subclassified, with 121 patients in type 1, 146 patients in type 2, and 86 patients in the type 3 USH group. The median age at presentation was 27 years (IQR: 17.5–38) years. There were 246 (61.35%) males and 155 (38.65%) females. Males were more commonly affected in all three subtypes. Defective night vision was the predominant presenting feature in all types of USH (type 1: 43 (35.54%), type 2: 68 (46.58%), and type 3: 40 (46.51%) followed by defective peripheral vision. Patients with type 2 USH had more eyes with severe visual impairment.

Conclusion:

RP in USH is commonly bilateral and predominantly affects males in all subtypes. Patients with USH and RP will have more affection of peripheral vision than central vision. The key message of our study is early visual and hearing rehabilitation in USH patients with prompt referral to otolaryngologists from ophthalmologists and vice versa.

Consanguinity and ocular disorders in India: Electronic medical records driven big data analytics

Purpose:

To describe the distribution of ocular disorders in patients with a family history of consanguinity presenting to a multi-tier ophthalmology hospital network in India.

Methods:

This cross-sectional hospital-based study included 2,805,267 new patients presenting between August 2010 and April 2021. Patients with a family history of consanguinity were included as cases. The sociodemographic and clinical data were collected using an electronic medical record system.

Results:

Overall, 20,445 (0.73%) new patients were documented to have a family history of consanguinity. The prevalence rates were 4.04% in children (age: <16 years) and 0.21% in adults. The mean age of the patients was 11.87 ± 11.06 years. The majority of the patients were males (56.48%) and students (54.43%) by profession. The majority (93.05%) of the patients were in the 0–30-years age bracket, with over half of them (53.71%) presenting in the first decade of life. A significant number of patients were from higher socioeconomic status (73.48%) and the rural region (47.62%). The most common degree of consanguinity documented was second degree (3.95%). The most common ocular disorders associated with a high proportion of consanguinity were congenital hereditary endothelial dystrophy (CHED) (100%), corneal macular dystrophy (83.78%), xeroderma pigmentosum (80.95%), and ocular albinism (73.59%). A tenth of the patients (9.8%) reported a similar history of ocular disorders among the family members and more commonly among the siblings (70.4%).

Conclusion:

Consanguineous marriages are not uncommon in India. They cause ocular disorders that cause visual impairment in a significant majority of those affected in their early decades of life. Genetic counseling plays a role in prevention.

Clinical profile and error of inclusion and exclusion in schools for the blind in Bangalore and a review of literature

Purpose:

To determine the causes of severe visual impairment and blindness in children in schools for the blind in the city of Bangalore, Karnataka and to determine the error of inclusion and exclusion from these schools.

Methods:

This was a cross-sectional study. Children in four schools for the blind were subjected to a detailed ophthalmic evaluation. The World Health Organization Program for Prevention of Blindness low-vision form was used to collect data. To know the educational background of children with visual disability of 40% or more (best-corrected visual acuity of ≤6/24 in the better eye), not in schools for the blind, we collected data by telephonic conversation after procuring their phone numbers from our low-vision clinic.

Results:

One-hundred-seventy-eight children were examined. The major site of anomaly causing blindness in 31% of children was optic nerve, followed by retina (24%), cornea (23%), and whole globe (22%). Avoidable blindness was 35.42%. Thirteen percent of the children with no visual disability were incorrectly enrolled in blind schools. We were able to contact 92 children with a visual disability of ≥40%. Seventy-eight children (84.78%) attended regular schools; these schools were bereft of a specially trained teacher to look after the needs of the blind.

Conclusion:

Avoidable blindness is still a cause for concern. Children should undergo eye-examination before being enrolled in schools for the blind to avoid errors of inclusion. Though integrated education for children with vision disability is a good approach, it requires teachers trained in teaching skills particular to blindness. Education for the visually impaired in India needs a major revision.

Tribal Odisha Eye Disease Study (TOES) Report # 9. Eye diseases and retinal disorders in an adult and elderly tribal community in Odisha, India - A community hospital-based study

Purpose:

To measure the proportion of people with major ophthalmic and retinal disorders in the tribal and non-tribal people presenting to a community eye hospital in an Indian state with a sizeable tribal population.

Methods:

Hospital-based cross-sectional retrospective study of all new adult patients, examined between September 2015 and June 2020. A tribal was defined as per the Indian ethnic classification. Blindness and visual impairment were defined as per the WHO standards. Diabetes and hypertension were defined as per Indian standards. The proportion of common ophthalmic and retinal disorders between the tribal and non-tribal community were compared.

Results:

This cohort consisted of 76,166 people (45.8%; n = 34,869, tribal); 39.4% (n = 29,989; non-tribal 23.6% and tribal 15.8%) people had ophthalmic disorders. In the examined people 2.3% were blind (higher in tribal community 4.7% versus 0.8%; P < 0.001) and 8.4% had moderate-to-severe visual impairment (higher in tribal community 14.4% versus 4.4%; P < 0.001). Refractive error (64.4%; higher in non-tribal community, 77.3% versus 44.6%, P < 0.001) and operable cataract (23.9%; higher in tribal community, 40.9% versus 11.8%, P < 0.001) were the principal ophthalmic disorders. Retinal disorders were higher in non-tribal people (5.9% vs. 2.9%; P < 0.001), but the tribal group had higher proportion of retinitis pigmentosa (20% vs. 6.4%; P < 0.001) and lower proportion of diabetic retinopathy (8% vs. 40.7%; P < 0.001).

Conclusion:

The health-seeking behavior of the tribal community in India is low. A tribal person in India apparently visits the hospital when vision is grossly affected. It calls for greater advocacy, increased access to healthcare, and a larger population-based study.

Analyzing Inbreeding and Estimating Its Related Deficiencies in Northeastern Brazil

This cross-sectional study aimed to observe number of marriages between relatives in São Francisco Valley municipalities and correlations between degrees of kinship and susceptibility to genetic diseases. Three hundred and nine (309) consanguineous couples were interviewed in five municipalities. The data were analyzed using SPSS (version 22), Chi-square testing, and the generalized estimating equation (GEE). In Pariconha-AL for first cousins, the results revealed significantly higher numbers of disabled children than for third cousins (p < 0.05). Of these, the prevalence for physical disability was significant (χ2 = 19.203, df = 4, p = 0.001). In the cities of Glória-BA (χ2 = 11.652, df = 3, p = 0.020) and OlhoD'água do Casado-AL (χ2 = 8.123, df = 4, p = 0.044), physical disabilities were also significantly higher in children from unions of first-degree cousins than for other degrees of kinship. Visual impairment was more significant in first-degree cousins in Glória-BA (χ2 = 14.206, df = 3 p = 0.007); yet among third-degree cousins, visual impairment in the municipality of Santa Brígida-BA was more prevalent (χ2 = 6.416, df = 2 p = 0.040). Inbreeding, as revealed in the evaluated cities, reinforces the hypothesis for developing genetic diseases.

[Association between consanguinity with the ocular congenital abnormalities in Togo]

OBJECTIVES

To investigate the possibility of an association between parental consanguinity and the occurrence of congenital ocular abnormalities.

MATERIALS AND METHODS

A retrospective cross-sectional study was carried out over 3 years, from January 2016 to December 2018, in the pediatric ophthalmology unit of the University Hospital Campus of Lomé (Togo). It included children with congenital ocular abnormalities. Age, gender, geographic origin (city or urban area, village or rural area), degree of consanguinity of parents and types of congenital ocular abnomalities were the variables of study. Odds Ratio (OR) and logistic regression were used to investigate the correlation between parental consanguinity and the occurrence of congenital ocular abnormalities. A P-value of<0.05 was considered statistically significant.

RESULTS

Among the 103 patients with congenital ocular abnormalities, there were 60 (58.2%) males and 43 (41.8%) females. The mean age of the patients was 16 months, range 1 month-5 years. Patients born to consanguineous parents were 26.2% (27) of the total population. Of these 27 patients, 25 (92.6%) were born to second-cousin marriages and 24 (88.89%) came from a rural area. Parental consanguinity was correlated with developmental abnormalities of the globe (OR=37.50; 95% CI_: [4.46-314.80]; r=3.62; P=0.00), sclerocornea (OR=13.04; 95% CI: [1.39-122.54]; r=2.57; P=0.02) and corneal dystrophy (OR=9.37; 95% CI: [0.93-94.36]; r=2.24; P=0.02).

CONCLUSION

Our study suggests the existence of a correlation between parental consanguinity and the occurrence of congenital ocular abnormalities.

Genetic and reproductive consequences of consanguineous marriage in Bangladesh

Introduction

This study aimed to assess the prevalence, sociodemographic factors, reproductive consequences, and heritable disease burdens associated with consanguineous marriage (CM) in Bangladesh.

Methods

A total of 7,312 families, including 3,694 CM-families, were recruited from 102 locales of 58 districts of Bangladesh. Using a standard questionnaire, we collected medical history and background sociodemographic data of these families. Family history was assessed by pedigree analysis. Fertility, mortality, secondary sex ratio, selection intensity, lethal equivalents were measured using standard methods.

Results

The mean prevalence of CM in our studied population was 6.64%. Gross fertility was higher among CM families, as compared to the non-CM families (p < 0.05). The rate of under-5 child (U5) mortality was significantly higher among CM families (16.6%) in comparison with the non-CM families (5.8%) (p < 0.01). We observed a persuasive rise of abortion/miscarriage and U5 mortality rates with the increasing level of inbreeding. The value of lethal equivalents per gamete found elevated for autosomal inheritances as compared to sex-linked inheritance. CM was associated with the incidence of several single-gene and multifactorial diseases, and congenital malformations, including bronchial asthma, hearing defect, heart diseases, sickle cell anemia (p < 0.05). The general attitude and perception toward CM were rather indifferent, and very few people were concerned about its genetic burden.

Conclusion

This study highlights the harmful consequences of CM on reproductive behavior and the incidence of hereditary conditions. It essences the need for genetic counseling from premarital to postnatal levels in Bangladesh.

Inherited eye diseases in Turkey: Current approaches and future directions

The aim of this review is to reveal Turkey's current status of medical practice in inherited eye diseases and the necessary steps to improve healthcare services and research activities in this area. Since consanguinity rate is high, disease burden is estimated to be high in Turkey. Universal health insurance system, easily accessible medical specialists, increasing genetic test, and counseling opportunities are the key advantages of Turkey's healthcare system. However, specialized clinics for inherited eye diseases, low-vision rehabilitation services, training of ophthalmologists about the recent developments in ocular genetics, and multidisciplinary translational research are the main headlines needed to be focused for better health services and successful research in Turkey.

Clinical and Molecular Disease Spectrum and Outcomes in Patients with Infantile-Onset Pompe Disease

OBJECTIVES

To evaluate the clinical and molecular spectrum, and factors affecting clinical outcome of patients in India diagnosed with infantile-onset Pompe disease (IOPD).

STUDY DESIGN

In this multicenter, cross-sectional study, we evaluated the records of 77 patients with IOPD to analyze their clinical course, outcomes, and factors influencing the outcomes.

RESULTS

Of the 77 patients with IOPD, phenotype data were available in 59; 46 (78%) had the classic phenotype. Overall, 58 of 77 (75%) and 19 of 77 (25%) patients were symptomatic before and after age 6 months, respectively. Alpha-glucosidase gene variant analysis available for 48 patients (96 alleles) showed missense variants in 49 alleles. Cross-reactive immunologic material (CRIM) status could be determined or predicted in 44 of 48 patients. In total, 32 of 44 patients (72%) were CRIM-positive, and 12 of 44 patients (27%) were CRIM-negative. Thirty-nine cases received enzyme-replacement therapy (ERT), alglucosidase alfa, and 38 patients never received ERT. Median age at initiation of ERT was 6.5 months. Response to ERT was better in babies who had CRIM-positive, non-classic IOPD.

CONCLUSIONS

This study highlights the clinical spectrum of IOPD in India and provides an insight on various factors, such as undernutrition, feeding difficulties, and recurrent respiratory infection, as possible factors influencing clinical outcomes in these patients. The study also reiterates the importance of raising awareness among clinicians about the need for early diagnosis and timely treatment of IOPD.