Ocular Manifestations of Sickle Cell Disease in Different Genotypes

ABSTRACT

Background

Sickle cell disease (SCD) is a multisystemic disorder with variable systemic involvement which varies according to genotype. In this study, our aim is to compare ocular complications between HbSS, HbSC, HbS/β+ thalassemia, HbS/β0 thalassemia, SS alpha thalassemia, and S/β0 + alpha thalassemia genotypes.

Methods

Data of patients included in this study was recruited from the Cooperative Study of Sickle Cell Disease (CSSCD). Patients with major sickle cell hemoglobinopathies (SS, SC, Sβ- thalassemia, SS alpha thalassemia) were eligible for enrollment, after that, a detailed eye exam was performed. We categorized ocular complications into conjunctival sign, iris atrophy, and both proliferative and non-proliferative sickle cell retinopathy.

Results

A total of 1867 patients were included in this study, with a mean age of 27.7 (± 11.7) years. They were 830 (44.5%) males and 1037 (55.5%) females. The most common genotype was SS with 971 (52%) patients, and the least common form was sickle cell with both alpha and beta thalassemia major with 42 (2.2%) patients. We found a significant difference in the frequency of proliferative sickle cell retinopathy, where SC genotype had the highest frequency and S B0 thalassemia genotype had the lowest frequency. We also found a significant difference in the frequency of conjunctival sign, where SS genotype had the highest frequency and the S B+ thalassemia has the lowest frequency.

Conclusion

We identified ocular complications for major sickle cell hemoglobinopathies, where we confirmed previous small study’s findings and identified ocular complications of less common hemoglobinopathies.

KEYWORDS:

• Sickle cell
• ocular
• eye
• genotype
• retinopathy

Acknowledgments

We would like to thank the Biologic Specimen and Data Repository Information Coordinating Center (BioLINCC) for providing the data for the Cooperative Study of Sickle Cell Disease (CSSCD) https://biolincc.nhlbi.nih.gov/studies/csscd/.

Declaration of interest

All authors have no conflicts of interest to disclose.

Data availability statement

The data described in this article are openly available in the Open Science Framework at DOI:10.17605/OSF.IO/TPA6U.