The kidneys are a pair of bean-shaped organs. Each kidney is about the size of a fist. The kidneys' function are to filter the blood in order to remove waste, control the body's fluid balance and regulate the balance of electrolytes.
Loss of kidney function may be acute or chronic. The former is usually reversible, while the latter is permanent.
. The higher you climb, the lower the amount of oxygen available to your body. The kidneys react to that by temporarily decreasing plasma volume.
There is concern that living at high altitude may accelerate the progression of chronic kidney disease. Many areas of the kidney are marginally oxygenated even at sea levels. Researchers postulated that arterial hypoxemia (abnormally low level of oxygen in the blood) at high altitude poses a risk of faster disease progression in those with preexisting kidney disease.
A survey in Tibet to identify the prevalence and associated risk factors of chronic kidney disease in subjects living at altitudes above 3500 meters clearly showed a higher number of people that suffered from High Altitude Kidney Disease. Which suggests that a chronic lack of oxygen causes chronic kidney diseases.
Much more information about Chronic Kidney Diseases of non-Traditional (CKDnT) causes can be found here.
 Goldfarb-Rumyantzev, Alper: Short-term responses of the kidney to high altitude in mountain climbers in Nephrology, Dialysis, Transplantation – 2014
 Luks et al: Chronic kidney disease at high altitude in Journal of the American Society of Nephrology – 2008
 Chen et al: Prevalence and risk factors of chronic kidney disease: a population study in the Tibetan population in Nephrology, Dialysis, Transplantation – 2011