Sickle Cell Maculopathy: Prevalence, Associations and Impact on Visual Acuity

ATYPICAL FOVEAL AND PARAFOVEAL ABNORMALITIES IN SICKLE CELL DISEASE

PURPOSE

The primary aim was to describe the patterns of paramacular involvement, not yet reported but that optical coherence tomography angiography can now detect in patients with sickle cell disease. The secondary aim was to search arguments concerning the physiopathogeny of paramacular involvement.

METHODS

This institutional cohort retrospective study was conducted in a Referral Center for Ophthalmological Rare Diseases. Follow-up included an ophthalmologic examination with optical coherent tomography and optical coherent tomography angiography.

RESULTS

One hundred and thirty-two patients with SCD were included. Typical sickle cell maculopathy was observed in temporal area in 84 eyes (40.0%) of SS patients and eight eyes (14.8%) of SC patients ( P < 0.001). Enlargement of the foveal avascular zone was observed in 10 eyes of eight SS patients. Two atypical parafoveal abnormalities were found in SS patients only. The first one consisted of macular thinning with normal vascularization in 15 eyes of 11 patients. The second atypical maculopathy was large areas of loss of vascularization without retinal thinning 10 eyes of six patients. Multivariate analysis did not show a statistically significant relation between the peripheral sickle retinopathy stage and the different type of sickle cell maculopathy ( P = 0.21).

CONCLUSION

Those atypical sickle cell maculopathy may correspond to early forms preceding a typical sickle cell disease maculopathy (SCDM). This would point toward several physiopathogenic mechanisms. The first one included the existence of ischemia that can be related to anemia. Presence of retinal thinning without vascular involvement point out to a neurogenic mechanism.

Sickle Eye Project: a cross-sectional, non-interventional study of the prevalence of visual impairment due to sickle cell retinopathy and maculopathy in the UK

INTRODUCTION

Sickle cell disease (SCD) is one of the most common genetic disorders in the UK, with over 15 000 people affected. Proliferative sickle cell retinopathy (SCR) is a well-described complication of SCD and can result in significant sight loss, although the prevalence in the UK is not currently known. There are currently no national screening guidelines for SCR, with wide variations in the management of the condition across the UK.

METHODS AND ANALYSIS

The Sickle Eye Project is an epidemiological, cross-sectional, non-interventional study to determine the prevalence of visual impairment due to SCR and/or maculopathy in the UK. Haematologists in at least 16 geographically dispersed hospitals in the UK linked to participating eye clinics will offer study participation to consecutive patients meeting the inclusion criteria attending the sickle cell clinic. The following study procedures will be performed: (a) best corrected visual acuity with habitual correction and pinhole, (b) dilated slit lamp biomicroscopy and funduscopy, (c) optical coherence tomography (OCT), (d) OCT angiography where available, (e) ultrawide fundus photography, (f) National Eye Institute Visual Function Questionnaire-25 and (g) acceptability of retinal screening questionnaire. The primary outcome is the proportion of people with SCD with visual impairment defined as logarithm of the minimum angle of resolution ≥0.3 in at least one eye. Secondary outcomes include the prevalence of each stage of SCR and presence of maculopathy by age and genotype; correlation of stage of SCR and maculopathy to severity of SCD; the impact of SCR and presence of maculopathy on vision-related quality of life; and the acceptability to patients of routine retinal imaging for SCR and maculopathy.

ETHICS AND DISSEMINATION

Ethical approval was obtained from the South Central-Oxford A Research Ethics Committee (REC 23/SC/0363). Findings will be reported through academic journals in ophthalmology and haematology.

Relationship between paramacular thinning, cerebral vasculopathy, and hematological risk factors in sickle cell disease

Purpose

To identify risk factors for sickle cell maculopathy due to hematological parameters (especially anemia and hemolysis) or cerebral vasculopathy.

Methods

This retrospective study was conducted at a Referral Center. The follow-up included optical coherent tomography/optical coherent tomography angiography, neuro-radiological imaging, and a hematological assessment (hemoglobin, hemoglobin S level, reticulocytes, mean corpuscular volume, bilirubin, and lactate dehydrogenase).

Results

Hundred and thirty-two sickle cell patients were included. Maculopathy was observed in 127 eyes of SS patients and 10 eyes of SC patients (p < 0.001), unrelated to peripheral retinopathy. Cerebral vasculopathy was more frequent in SS patients (p < 0.001) and was also associated with the presence of maculopathy (p = 0.049), and it was related to peripheral retinopathy (p < 0.001). All biological parameters significantly differed according to the genotype (p < 0.001) but not according to the presence of cerebral vasculopathy or maculopathy. In the multivariate analysis, reticulocytes and bilirubin were associated with the presence of cerebral vasculopathy and maculopathy.

Conclusion

The data obtained were consistent with the role of anemia or hemolysis markers in cerebral vasculopathy and macular involvement. As a trend of hemolysis appears to be a risk factor for these complications, this validates the use of preventive plasmapheresis in these patients.

Risk factors associated with sickle cell retinopathy: findings from the Cooperative Study of Sickle Cell Disease

Background

Sickle cell retinopathy (SCR) is one of the most important ocular manifestations of sickle cell disease (SCD). This study aims to assess the prevalence of SCR in SCD, identify risk factors for its development and progression to proliferative sickle cell retinopathy (PSCR), and evaluate the potential implications of these results on clinical practice.

Methods

This research is a secondary analysis of patients diagnosed with SCD from the epidemiological, multicenter Cooperative Study of Sickle Cell Disease (CSSCD). We included all patients who completed a full ophthalmic evaluation. We identified clinical and laboratory SCD characteristics associated with SCR using multivariate logistic regression models. Proliferative sickle cell retinopathy (PSCR) was diagnosed according to the Goldberg classification system.

Results

Of the 1904 study participants with SCD who met the inclusion criteria, 953 (50.1%) had retinopathy; of which 642 (67.3%) had bilateral disease. SCR was associated with older age (p < 0.001), history of smoking (p = 0.001), hematuria (p = 0.050), and a lower hemoglobin F (HbF) level (p < 0.001). PSCR risk increased with smoking (p = 0.005), older age (p < 0.001) higher hemoglobin level (p < 0.001) and higher white blood cell count (p = 0.011). Previous blood transfusion (p = 0.050), higher reticulocyte count (p = 0.019) and higher HbF level (p < 0.001) were protective factors against the development of PSCR. Ocular symptoms were associated with progression to PSCR in patients with SCR (p = 0.021).

Conclusion

In this cohort of individuals with SCD, half of the participants had signs of SCR. Smoking and blood hemoglobin level were the two modifiable risk factors associated with increased retinopathy progression. Screening to identify the different stages of retinopathy, actively promoting smoking cessation, and optimizing the hematological profile of patients with SCD should guide treatment protocols designed to prevent the vision-threatening complications of the disease.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40942-022-00419-8.

Hematopoietic Stem Cell Transplant for Sickle Cell Disease: PATIENT SELEction and Timing Based on Sickle Cell-Related Multiple Chronic Conditions

Hematopoietic stem cell transplant (HSCT) is the only cure for patients with sickle cell disease (SCD). Although most SCD patients experience progressive end-organ damage and shortened lifespans, not all patients follow the same disease course, tempo, or outcome. Therefore, the dilemma facing physicians is weighing the selection of patients and timing for the procedure against donor type and transplant-related mortality and morbidity that go up with increasing age. On the other hand, the dilemma facing the patients and families is how acceptable HSCT that carries some mortality risks to them. We have analyzed the chronic conditions due to SCD in 449 patients to determine whether SCD-related multiple chronic conditions (MCC) can be risk-stratified to identify the group of patients predicted to not only have shortened lifespans but also functional limitation and poor quality of life so that these at-risk patients can be offered HSCT early and before MCC develops. We identified that the age of onset of the first SCD-related chronic conditions strongly predicted for the risks for disease-related MCC. SCD patients who suffered their first disease-related chronic condition before age 30 years developed MCC at a rate of 19.1 times faster than those at a later age. These patients are therefore high-risk patients and should be offered HSCT early in the course of their disease before multiple organ damage intervenes, even if matched-related donors are not available. This patient selection and timing approach provides a forum for an easy-to-understand and real-time discussion, including the choice of donor type, with SCD patients and families when considering HSCT.