OP, has the doctor told you any other issues have been found and/or any irregular screenings?
What’s the outlook for people with horseshoe kidney?
Horseshoe kidney usually does not cause serious health problems. You or your child may need ongoing care to manage symptoms, but you can live a full, active life with horseshoe kidney. Horseshoe kidney usually does not affect life expectancy.
People with horseshoe kidney may be at higher risk for kidney (renal) cancer. Keep an eye out for symptoms, and talk to your healthcare provider about steps you should take to stay on top of your kidney health.
https://my.clevelandclinic.org/health/diseases/21745-horseshoe-kidney-renal-fusion