Early renal damage in patients with sickle cell disease in sub-Saharan Africa: a multinational, prospective, cross-sectional study
Background Chronic kidney disease is one of the leading causes of mortality in patients with sickle cell disease.
However, it has been almost exclusively studied in patients with the SS phenotype and in high-income countries,
despite more than 80% of patients living in Africa. We looked for the determinants of glomerulopathy in a
multinational cohort of patients with sickle cell disease of diff erent phenotypes in sub-Saharan Africa.
Methods In the CADRE cohort, we prospectively included patients 3 years and older with sickle cell disease of all
haemoglobin phenotypes in Cameroon, Côte d’Ivoire, Mali, and Senegal. All individuals were assessed at steady state.
The main outcome of interest was albuminuria defi ned as a urine albumin-to-creatinine ratio of greater than 30 mg/g.
We investigated the clinical and biological determinants (including haemolysis markers) of albuminuria in two main
phenotype groups (SS and S??; SC and S?+) with further stratifi cation by age and country.
Findings The study is ongoing because of follow-up. 2582 patients with sickle cell disease were included (1776 SS,
136 S??, 511 SC, and 159 S?+). 644 patients with the SS and S?? phenotypes (33·7%, 95% CI 31·6–35·8) and 110 with
the SC and S?+ phenotypes (16·4%, 13·6–19·2) had albuminuria. In the SS and S?? group, albuminuria was detected
in 144 (27%) of 527 children younger than 10 years and its frequency increased with age (29 [48%] of 60 patients aged
>40 years). Multivariable analysis showed that albuminuria was associated with age (odds ratio 1·43, 95% CI
1·20–1·71; p<0·0001), female sex (1·35, 1·02–1·82; p=0·045), low haemoglobin (0·79, 0·66–0·93; p=0·006), high
lactate dehydrogenase concentrations (1·33, 1·14–1·58; p=0·0009), and, using Côte d’Ivoire as the reference, Mali
(2·49, 1·64–3·79; p=0·042) and Cameroon (1·59, 1·01–2·51; p=0·0007) in patients with the SS and S?? phenotypes.
The magnitude of the association of albuminuria with haemoglobin and lactate dehydrogenase concentrations
increased with age. In the SC and S?+ patients, only low haemoglobin (0·69, 0·48–0·97; p=0·029), high blood
pressure (1·63, 1·17–2·27; p=0·0017), and Mali (3·75, 1·75–8·04; p<0·0001) were associated with albuminuria.
Interpretation Hyperhaemolysis is associated with albuminuria, with an age-dependent eff ect, in the SS and S??
phenotypes only, suggesting a diff erent pathological mechanism for glomerular disease in the patients with SC and
S?+ phenotypes. However, both phenotypes are associated with a high prevalence of albuminuria in childhood.
Therefore, screening for albuminuria is advised in African children with sickle cell disease to detect early renal damage.
Funding Paris Cité Sorbonne University (GrEX project) and Cardiology and Development.
Auteur(s) : Ranque B, Menet A, Diop IB, Thiam MM, Diallo D, Diop S, Diagne I, Sanogo I, Kingue S, Chelo D, Wamba G, Diarra M, Anzouan JB, N’Guetta R, Diakité CO,
Pages : 64-73
Année de publication : 2014
Revue : Lancet Haematology
N° de volume : 1
Type : Article
Mise en ligne par : DEME Indou