Floating kidney, which may also be called hypermobile kidney or wandering kidney, is known by the medical name of nephroptosis. It is a condition that causes the kidney to drop downward, especially when a person stands up or goes from a lying down to upright position. This can also be called prolapse or kidney prolapse. The downward movement of the kidney suggests it is not fully fixed in place by the tissues that surround it, and it’s a condition that’s been noted for more than a century by physicians.
Those most commonly affected by this disorder are young women, usually women who are thin and have long waists. Rarely, the condition can be caused by congenital defect. Injury to the kidney or a blow to the area just above or below the kidney can also occasionally cause floating kidney. More commonly mobility of the kidney occurs without any injury.
The kidneys are usually supported by tissue called perirenal fasciae, which is soft tissue that is part of connective tissue. When perirenal fasciae are not present in abundance, the floating kidney is not fixed in place, and upon standing it can drop as low as the pelvis. This may or may not cause symptoms. When symptoms emerge, they can be distinctly uncomfortable and include pain in the flank, chills, nausea, and elevated blood pressure. The displacement of the kidney may also cause the ureter, the structure that passes urine from the kidneys to the bladder to kink. This can result in extreme pain upon or difficulty urinating.
Diagnosis tends to be made by taking a series of x-rays in a supine (lying down position) and then in an upright or standing position. These can tell pretty definitely whether the kidney is truly moving downward when a person stands or whether some other condition may be causing the symptoms. Most people are unaware they have the disorder, and usually only emergence of symptoms prompts evaluation for the condition. If the condition is symptomless and diagnosed, it usually requires no treatment.
For those suffering from symptoms of floating kidney, treatment usually exists in the form of kidney surgery called nephrophexy. In the past, this surgery was considerably more invasive but it now may be performed via laparoscopic techniques, resulting in much quicker recovery time. The surgery essentially fixes the kidney in place, reducing its mobility and ending painful symptoms.
Most people with floating kidney have few if any complications, and even when requiring surgery, the surgery itself has an excellent outcome. This is not thought of as a fatal condition, since treatment is readily available. It can be highly uncomfortable, but many who have the condition may not feel discomfort. In numerous cases, people live their whole lives with nephroptosis without being aware they have it.
