Another common example is something called the “ectopic kidney.
These structures will eventually form the kidney and the ureter.
Why do we need to understand this formative process?
John Kelly / Tetra / Getty Images
This process is called rotation, while the ascent of a kidney to its final location is called migration.
This process is completed by the time an embryo is 8 weeks old.
Horseshoe Kidney Formation
A horseshoe kidney is what we call a “fusion anomaly.”
As the word suggests, a fusion anomaly will occur when one kidney gets attached to the other.
This will occur because of any disruption with the normal migration process of both kidneys.
This is referred to as a “crossed fused ectopic kidney.”
The fused portion of the kidney is referred to as the “isthmus.
This isthmus may or may not lie symmetrically over the spine.
However, this is the reported incidence only.
Symptoms
The majority of people born with horseshoe kidney won’t have symptoms.
In fact, horseshoe kidneys are often incidentally picked up on imaging studies that are done for other reasons.
“The reasons for this risk are not fully understood.
Normal human kidneys which sit higher up and are not connected together are typically not at as much risk.
Diagnosis
As mentioned above, horseshoe kidney will typically be detected on incidental abdominal imaging.
Further investigations are usually needed if the above-described symptoms, signs, or complications have been noted.
The patient, however, should still be warned about the susceptibility of their kidney to blunt abdominal trauma.
In most patients, the long-term prognosis is good.
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