CKD of Unknown Cause: A Global Epidemic?

World Kidney Day is an appropriate time to reflect on the epidemics(s) of chronic kidney disease (CKD) of undetermined cause (CKDu) that are affecting agricultural communities in Central America, South Asia, and possibly other parts of the world.1–4 The cause(s) of CKDu remain to be established, with heat, pesticides, water (including heavy metals), infections, or other factors being suggested as the primary cause(s). However, we still do not know, at least on a global level, who gets this disease, or even if the disease is the same in different parts of the world.