Aspects of Chronic Kidney Disease-Mineral and Bone Disorder (CKD-MBD) in Chronic Hemodialysis Patients in Resource-Limited Countries: An Example of the Aristide Le Dantec University Hospital in Dakar (Senegal)

Introduction: Chronic kidney disease–mineral and bone disorder (CKD-MBD) are frequently encountered in chronic dialysis patients and are responsible for heavy morbidity and mortality with an impairment of their quality of life. Few studies are available in sub-Saharan Africa. The objectives of this study were to determine its prevalence in our resource-limited context, and to study its types, biological and therapeutic aspects.

Patients and methods: This is a single-center descriptive and analytical cross-sectional study over 15 months carried out in the dialysis units (hemodialysis and peritoneal dialysis) of the nephrology department at the Aristide Le Dantec University Hospital in Dakar. Patients on chronic dialysis for more than 3 months who had completed a complete phospho-calcium assessment during the study period were included.

Results: Eighty-three chronic dialysis patients were studied, among whom 76 patients (91.5%) had MBD. The average age of the patients was 47.94±13.41 years with a sex ratio of 0.9. The first causal nephropathy was hypertensive nephropathy found in 40.8% of cases. Length of time on dialysis was 7.46±3.71 years. Fifty-nine patients (i.e., 93.6% of cases) benefited from 3 hemodialysis sessions per week and 13 patients benefited from PD. Fifty patients (65.78%) had secondary hyperparathyroidism, 22 patients (28.94%) had tertiary hyperparathyroidism, 3 patients (3.94%) had adynamic bone disease, 1 patient (1.31%) had osteomalacia. For hyperparathyroidism, the average PTHi was 1555.55±1223.94 ng/ml (or 23.94 times of the upper limit of normal (ULN)). Insufficiency and deficiency of 25-OH Vitamin D were noted respectively in 68.42% and 1.32% of patients. Therapeutically, 48.68% of patients had received treatment based on calcium carbonate, 5.26% of patients had received treatment based on non calcium-based phosphate binders, 68.42% of patients had received vitamin D and 6.5% of cases had benefited from treatment with calcimimetics. Parathyroidectomy was performed in 21% of cases. Three patients had adynamic bone disease, the average age was 46.33±13.6 years. The average PTH was 56.33 ng/ml, the average serum calcium was 82.73 mg/l, the average serum phosphate was 45.23 mg/l and the average vitamin D was 32.13 ng/ml, only one patient had osteomalacia. Seven patients (11.5% of cases) had vascular calcifications.

Conclusion: CKD-MBD are common among our hemodialysis patients, hence the need to implement a diagnostic and therapeutic strategy to better prevent them and, if necessary, manage them.

Keywords: CKD-MBD, Hyperparathyroidism, Adynamic bone disease, Osteomalacia, Chronic dialysis.