Mesoamerican Nephropathy and Kidney Disease Progression: A Case Series of Individuals With Kidney Biopsies From Nicaragua and El Salvador

Abstract

Mesoamerican Nephropathy and Kidney Disease Progression: A Case Series of Individuals With Kidney Biopsies From Nicaragua and El Salvador To the Editor: Mesoamerican nephropathy (MeN) is a chronic kidney disease affecting rural populations in Central America, especially sugarcane workers. Prospective studies and data regarding the natural history of the disease are scarce. We have previously described kidney morphology and biochemical characteristics of MeN in 2 case series, including a 1-to-2-year-long follow-up where mean estimated glomerular filtration rate (eGFR) decline was 4.4 mL/min/1.73 m per year. Another 2-year-long prospective study of young rural men with chronic kidney disease in Nicaragua without kidney biopsies reported an average eGFR decline of 3.8 mL/min/1.73 m. We now report eGFR trends in individuals with MeN with kidney biopsies over a period of 5-7 years. Participants from our previous kidney biopsy studies in El Salvador and Nicaragua were invited to participate in this long-term follow-up. Blood and urine samples were collected and the subset of participants from Nicaragua also completed a questionnaire regarding work history. eGFR was calculated using the CKD-EPI equation. Samples were analyzed at the same local laboratory as in the baseline study. Kidney biopsy findings at baseline are described in previous publications. In hypothesis-generating analyses, associations between baseline biopsy findings and progression rate were calculated using linear regression for continuous variables and 1-way analysis of variance for categorical variables (GraphPad). Ethics committees at Hospital Nacional Rosales, El Salvador (ACTA EXP. No 11/ 2016), the National Autonomous University of Nicaragua, Nicaragua (ACTA No 31 and 83), and Stockholm, Sweden (Dnr 2015/849-32) approved the study. New written informed consent was collected from Nicaragua participants. No new informed consent was required from the