Chronic kidney disease of unknown origin: An agricultural occupational hazard

Chronic kidney disease (CKD) is a worldwide public health problem with increasing incidence and prevalence.1 In areas of Central America, an epidemic of CKD of unknown causes (CKDu) has emerged particularly in young men of working age.2,3 Studies to date are limited; however, results have not linked CKD with the commonly known risk factors (diabetes, hypertension, obesity) within this population. Consistently identified factors include agricultural work at low altitudes. Higher temperatures associated with low altitudes cause heat related illnesses and dehydration which can impact kidney function. The purpose of this study was to determine the environmental heat exposure of sugar cane harvesters working within Guanacasta Sur, Nicaragua where 46% of all male deaths from 2002 to 2012 were caused by CKDu.4 The U.S. National Institute for Occupational Safety and Health(OSHA) has designed a bilingual Iphone app for farm owners to monitor heat and humidity in order to implement safe work practices according to scientific recommendations. Results using the Heat Stress App and online weather information indicate an average heat index of high to extreme caution during the harvest season. The high risk level of heat related illness coupled with self-reported poor hydration practices of sugar cane workers may explain the increased prevalence of CKDu in this population. However, this type of work has been occurring for many years, yet the rate and severity of CKDu has been rapidly on the rise. Environmental exposures and other unknown factors should be considered to rule out the unknown origins of this fatal disease.