1. Nephrology Unit, Kinshasa University Hospital, Kinshasa, Democratic Republic of the Congo
2. Department of Medicine, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
3. Directorate of Medicine, Komfo Anokye Teaching Hospital, Kumasi, Ghana
4. Renal Unit, Uniosun Teaching Hospital Osogbo, Osun State University, Osogbo, Osun State, Nigeria