Kidney shrinking, also known as atrophic kidney, refers to reduction of kidney size. Small kidney doesn’t mean kidney shrinking, since kidney sizes may be different due to age, gender, stature and weight. Kidney shrinking may be the result of shortage blood supply to kidney or the thinning of renal parenchyma. In this article, several common reasons of kidney shrinking are listed as below:
1. Chronic kidney infections, such as pylonephritis can affect the nephrons, causing damage to renal parenchyma.
2. Renal ischemia caused by kidney disease or other reasons lead to less blood to kidney. Blood clot or accumulation of fat in blood vessel can be a reason of renal ischemia. Inadequate circulation of blood decrease the oxygen and nutrients supply to kidney.
3. Obstruction of urinary tract and reflux nephropathy could harm renal parenchyma. Reflux nephropathy means urine goes back from bladder to kidney. Reflux can occur when ureters do not attach properly to the bladder or valves do not work well. Over time, the kidneys may be damaged or scarred by this reflux.
4. In renal aplasia, the kidney size is less 50% of the normal kidney size. Renal aplasia is due to obstacles blood supply in embryonic period or other reasons that nephridial tissue can’t develop sufficiently.
With the kidney get smaller, more kidney function will be lost. Thus, kidney size can reflect the damage of kidney. Most of kidney shrinkage has slow progression and in the early stage, patients don’t feel any symptoms. When the kidney loses more than 50% of its function, some symptoms occur. Patents should be cautious of the causes of kidney shrinking. Once they have some symptoms, they should check their body timely for delaying the disease.