Staneva, Rada G., Balabanski, L., Dimova, I., Rukova, B., Hadjidekova, S., Dimitrov, P., Simeonov, V., Ivanov, S., Vagarova, R., Malinov, M., Cukuranovic, R., Stefanovic, V., Polenakovic, M., Djonov, V., Galabov, A., and Toncheva, D.
BEN is a primary, chronic tubulointerstitial nephritis characterized with chronic anemia, absence of edema, xantoderma, normal blood pressure and normal findings on the fundus oculi. The disease is distributed in restricted areas in Bulgaria, Romania, Croatia, Bosnia, Former Yugoslavia. Despite numerous studies on genetic and environmental factors and their possible involvement in BEN, its etiopathogenesis still remains elusive.