Epidemic of Chronic Kidney Disease in Agricultural Communities in Central America. Case definitions, methodological basis and approaches for public health surveillance

ABSTRACT

In the last four decades, increasing numbers of young people, in clusters of vulnerable farming communities in several Central American countries, have developed a severe form of kidney failure of uncertain etiology (thus termed chronic kidney disease of nontraditional causes, or CKDnT, in this publication). This type of chronic kidney disease, primarily a form of chronic interstitial nephritis, has reached epidemic proportions, devastating entire communities and overwhelming health systems. A recent analysis estimated that more than 60,000 renal failure (a proxy of CKDnT) deaths (41% among those younger than 60 years of age) occurred between 1997 and 2013 in Central America. CKDnT is characterized by progressive renal insufficiency, often diagnosed at a very late stage, in the absence of early symptoms, necessitating renal replacement therapy if the patient is to survive...This document presents a background to this epidemic, including its epidemiology and main hypothetical risk factors of CKDnT. It also includes a description of clinical and pathological characteristics, the case definitions for CKDnT surveillance, and the methodological basis and approaches for public health surveillance. The Pan American Health Organization (PAHO) Resolution on Chronic Kidney Disease in Agricultural Communities in Central America has recommended a set of priorities to address this epidemic; this document specifically addresses the request for a framework for systematic surveillance of CKD and CKDnT to be developed in the region, particularly for affected countries. This document presents a surveillance framework which includes (a) passive surveillance, with the main components based on mortality registries and on a population registry of dialysis or end-stage kidney disease; (b) active surveillance that could be based mainly on sentinel surveillance in communities and in selected occupations; and (c) population-based surveillance, through repeated cross-sectional surveys such as the WHO STEPS, which is a stepwise approach to surveillance for non-communicable diseases (NCDs).