Sickle cell retinopathy and other chronic complications of sickle cell anemia: A clinical study of 84 Sub-Saharan African cases (Cameroon)

Natural history and rate of progression of retinopathy in adult patients with sickle cell disease: an 11-year follow-up study

Sickle cell retinopathy (SCR) is a complication of sickle cell disease (SCD). Proliferative SCR (PSCR) can lead to severe visual impairment due to vitreous hemorrhage or retinal detachment. Knowledge of risk factors for progression and complications of SCR is limited. The aim of this study is to describe the natural history of SCR and to identify risk factors for progressive SCR and development of PSCR. We retrospectively analyzed disease progression in 129 patients with SCD with a median follow-up period of 11 years (interquartile range, 8.5-12). Patients were divided in 2 groups. The genotypes hemoglobin SS (HbSS), HbSβ0-thalassemia, and HbSβ+-thalassemia were grouped together (n = 83; 64.3%), whereas patients with HbSC (n = 46; 35.7%) were grouped separately. Progression of SCR was observed in 28.7% (37 of 129) of patients. Older age (adjusted odds ratio [aOR], 1.073; 95% confidence interval [CI], 1.024-1.125; P = .003), HbSC genotype (aOR, 25.472; 95% CI, 3.788-171.285; P ≤ 0.001), and lower HbF (aOR, 0.786; 95% CI, 0.623-0.993; P = .043) were associated with PSCR at end of follow-up. Lack of any SCR at end of follow-up was associated with female sex (aOR, 2.555; 95% CI, 1.101-5.931; P = .029), HbSS/HbSβ0/HbSβ+ genotype (aOR, 3.733; 95% CI, 1.131-12.321; P = .031), and higher HbF levels (aOR, 1.119; 95% CI, 1.007-1.243; P = .037). Differentiated strategies for screening and follow-up of SCR could be considered for patients at low or high risk.

Do We Store Packed Red Blood Cells under "Quasi-Diabetic" Conditions?

Red blood cell (RBC) transfusion is one of the most common therapeutic procedures in modern medicine. Although frequently lifesaving, it often has deleterious side effects. RBC quality is one of the critical factors for transfusion efficacy and safety. The role of various factors in the cells’ ability to maintain their functionality during storage is widely discussed in professional literature. Thus, the extra- and intracellular factors inducing an accelerated RBC aging need to be identified and therapeutically modified. Despite the extensively studied in vivo effect of chronic hyperglycemia on RBC hemodynamic and metabolic properties, as well as on their lifespan, only limited attention has been directed at the high sugar concentration in RBCs storage media, a possible cause of damage to red blood cells. This mini-review aims to compare the biophysical and biochemical changes observed in the red blood cells during cold storage and in patients with non-insulin-dependent diabetes mellitus (NIDDM). Given the well-described corresponding RBC alterations in NIDDM and during cold storage, we may regard the stored (especially long-stored) RBCs as “quasi-diabetic”. Keeping in mind that these RBC modifications may be crucial for the initial steps of microvascular pathogenesis, suitable preventive care for the transfused patients should be considered. We hope that our hypothesis will stimulate targeted experimental research to establish a relationship between a high sugar concentration in a storage medium and a deterioration in cells’ functional properties during storage.