Horseshoe Kidney: Causes, Symptoms, and Treatment
Medically reviewed by Achuta Uppu, MD, Internal Medicine. Last reviewed: October 23, 2026.
What kind of doctor treats Horseshoe Kidney?
A urologist, a doctor who treats the kidneys and urinary tract, usually cares for horseshoe kidney. A nephrologist, a kidney doctor, can also help. A direct primary care or concierge doctor can be a first stop for an evaluation and can refer you to a specialist when needed.
What is horseshoe kidney?
Horseshoe kidney is the most common kidney fusion problem that is present from birth. In this condition, the two kidneys fuse, most often at their lower ends. The joined part is called the isthmus. The joined kidneys form a U shape, like a horseshoe.
The kidneys also sit in an unusual spot and are not turned the usual way. It affects about 1 in 400 to 600 people. It is about twice as common in males as in females.
Symptoms
Horseshoe kidney often causes no symptoms. It is often found by chance on a scan done for another reason. When symptoms do appear, they usually come from a blockage, kidney stones, or infection.
Problems that can happen include:
- A blockage where the kidney meets the ureter, the tube that carries urine to the bladder. This is the most common problem and affects about one-third of people.
- Kidney stones, which are seen in 16% to 60% of people with horseshoe kidney.
- Urinary tract infections, which can happen in up to one-third of people with it.
- Tumors. The risk of some kidney tumors, both harmless and cancerous, is higher than usual.
- Injury. The joined part sits low in the belly, and the ribs do not protect it as they do normal kidneys.
Causes and who gets it
Horseshoe kidney forms before birth, usually in the fourth to sixth weeks of the baby's development. Experts think several factors may play a part. These can include things in the womb, like exposure to harmful substances, and gene or chromosome changes.
In some cases, more than one person in a family has horseshoe kidney. Horseshoe kidney occurs in 14% to 20% of people with Turner syndrome. It is also linked to Edwards syndrome (trisomy 18) and Patau syndrome (trisomy 13). It can also occur along with differences in the heart, nervous system, bones, or genital and urinary organs.
How doctors diagnose it
Imaging tests, which take pictures of the inside of the body, help doctors find horseshoe kidney and its problems. A CT scan is the test of choice to see the kidneys and the tissue around them. An MRI can give similar information without the risk of radiation. An ultrasound can show the joined part, but it can miss horseshoe kidney in some people. Plain x-rays are not good at finding it.
Reflux, a backward flow of urine, is seen in about half of people with horseshoe kidney.
Treatment
Treatment depends on which problem a person has, since symptoms usually come from a blockage, stones, or infection.
A blockage may first be drained with a tube placed through the skin into the kidney, or with a stent placed in the ureter, until surgery can be done. Surgery to fix a blockage rebuilds the spot where the ureter meets the kidney. Some of these operations can be done through small cuts, which is called laparoscopic surgery.
Kidney stones may be treated with shock waves, called ESWL, or with surgery. In a serious kidney infection, a drain placed through the skin can keep the kidney stable until antibiotics take effect.
Small tumors can sometimes be treated with heat or cold probes instead of surgery. For some tumors, surgeons remove only part of the kidney to protect kidney function. Surgery for tumors is harder because of the unusual shape of the fused kidney.
When to see a doctor
Get prompt care for a urinary infection, because infection is the most common cause of death in people with horseshoe kidney. After an injury to the lower belly, get checked promptly, especially if you see blood in your urine.
Call 911 or go to the emergency room if you have severe belly pain, fainting, a sudden change in mental state, or sudden, severe pain anywhere in the body.
How a direct primary care or concierge doctor fits in
A direct primary care doctor charges a flat monthly fee instead of billing insurance, while a concierge doctor usually charges more and often works alongside insurance. Either can arrange scans, review results, and follow up over time for urinary infections or stones. They can also refer you to a urologist when a blockage, stone, or tumor needs treatment.
Common questions
Is horseshoe kidney common?
Yes, it is the most common kidney fusion problem present from birth. It is seen in about 1 in 400 to 600 people.
Does horseshoe kidney always cause symptoms?
No, many people have no symptoms. It is often found by chance on a scan done for another reason.
Can horseshoe kidney lead to kidney stones or infections?
Yes, it can raise the chance of both. Kidney stones are seen in 16% to 60% of people with horseshoe kidney.
Does horseshoe kidney run in families?
It can in some cases, but the cause is not fully clear. Experts think several factors may play a part.
Who is more likely to have horseshoe kidney?
Males are about twice as likely as females to have it. It is also seen in 14% to 20% of people with Turner syndrome.
Sources
- National Library of Medicine (PubMed Central) - Multimodality imaging spectrum of complications of horseshoe kidney
- National Library of Medicine (PubMed Central) - Reviewing the complexities of horseshoe kidney: insights into embryogenesis and surgical considerations
Medical Disclaimer
This content is for general educational and informational purposes only and is not medical advice. It is not a substitute for professional medical advice, diagnosis, or treatment, and reading it does not create a doctor-patient relationship. Always seek the advice of your physician or another qualified health provider with any questions about a medical condition, and never disregard or delay seeking professional advice because of something you read here. If you think you may have a medical emergency, call 911 (or your local emergency number) immediately.
