Pathology of Uddanam Endemic Nephropathy

In the last decade, pockets of endemic nephropathy have been recognized worldwide, in regions of Central America, Sri Lanka, and India. In India, the nephropathy has been recognized in the Uddanam area of north Andhra Pradesh and has been termed the Uddanam endemic nephropathy (UEN). The disease is distinctive in that besides the geographic distribution, it affects rural populations engaged in farm labor and agriculture, often silent in the initial phase with most patients presenting with advanced renal failure. The renal biopsy findings in all geographic areas including UEN have been one of a chronic tubulointerstitial nephritis with varying degrees of tubular injury, interstitial inflammation, tubular atrophy, and interstitial fibrosis with nonspecific glomerular obsolescence and lack of immune deposits. More recently, the demonstration of dysmorphic lysosomes in renal biopsies has favored a toxic etiology. There are thus many gaps in the understanding of this serious disease prevalent among poorer populations.