

While the etiology of the disease remains unknown, a favorite hypothesis is that it may relate to recurrent volume depletion and dehydration. Renal biopsies, when performed, show chronic tubulointerstitial disease, often with evidence for glomerular ischemia. Most subjects are used to working many hours in sugarcane fields under very hot conditions, and dehydration is common in this group. The condition is distinct from other major causes of CKD such as high blood pressure and diabetes. The disease, which has been named Mesoamerican Nephropathy, is being observed at remarkable frequency among male agricultural workers on the Pacific Coast, particularly in Nicaragua and El Salvador. This has been highlighted in recent studies investigating a mysterious form of CKD that has been epidemic in Central America. In recent years, the concept that dehydration does not cause CKD has been challenged. Thus, a whole new area of investigation is developing that focuses on the role of water and osmolarity and their influence on kidney function and health. Furthermore, there is some evidence that increasing hydration, particularly with water, may actually prevent CKD.

The discovery of these pathways has also led to the recognition that mild dehydration may be a risk factor in progression of all types of chronic kidney diseases. Three major potential mechanisms have been identified, including the effects of vasopressin on the kidney, the activation of the aldose reductase-fructokinase pathway, and the effects of chronic hyperuricemia. This has led to studies investigating whether recurrent dehydration may lead to permanent kidney damage. Recently, an epidemic of chronic kidney disease has emerged in Central America in which the major risk factor seems to be recurrent heat-associated dehydration. Dehydration, a condition that characterizes excessive loss of body water, is well known to be associated with acute renal dysfunction however, it has largely been considered reversible and to be associated with no long-term effects on the kidney.
