1. Department of Internal Medicine, Catholic University of Allied and Health Sciences, P. O. Box 1440, Mwanza, Tanzania
2. Department of Internal Medicine, Bugando Medical Centre, P.O. Box 1370, Mwanza, Tanzania
3. Department of Medicine, College of Health Sciences, University of Dodoma, P. O. Box 395, Dodoma, Tanzania
4. Renal Unit, Department of Internal Medicine, The Aga Khan Hospital, P.O. Box 2289, Dar es Salaam, Tanzania