Horseshoe Kidney

Earlier this year I did a recovery from a donor and in the OR we discovered, unknown to everyone including her family, that she had a horseshoe kidney. According to this case study from Britain, such a kidney can be transplanted into a recipient with good results.

This is supported by data from Stroosma et al (2001). 13 In this article,
eight horseshoe kidneys transplanted en bloc and 26, which were split and
transplanted into 47 recipients, were compared with 110 transplants in a
control group. No significant differences were found either in the short- or
long-term post-transplant results. Furthermore, no difference was noted between
results from en bloc or spit horseshoe kidneys.
13,18

Last I heard, the recipient of our donor was doing well, also.

According to my mom, I had a great-aunt who had a horshoe kidney. She died young, but not from kidney disease. I think she had cancer. Apart from being a colorful character and a bit of a hellraiser, she had no other issues.

A horseshoe kidney is what happens when both kidneys become joined at one pole, usually the lower pole. This happens during fetal development, during the 5-12mm embryonic stage when the kidneys are still in the true pelvis and the renal capsule is not yet fully developed. Of kidney fusion anomalies, horseshoe is the most common. It has an occurence of 1 in 400 births worldwide and is not linked to genetics. There have been cases where one identical twin has a horseshoe kidney and the other does not. There is some thought that positioning of the fetus in utero can cause the anomaly, as the kidneys migrate up from the true pelvis into their normal dorsolumbar position. The cause, however, is not really known.

Many individuals with a horseshoe kidney go through life with no idea they have it. Symptoms include frequent UTIs, kidney stones, hydronephrosis, and ureteropelvic junction obstruction, due to the high insertion of the ureter. There is also a higher risk of trauma to the isthmus because it lies anteriorly to the spine. Treatment is usually reserved for when the patient becomes symptomatic; antibiotics for infections, and surgical or nonsurgical interventions for hydronephrosis or stones.

In about 1/3 of all cases, there are additional congenital abnormalities, often occuring along the midline of the body: hydrocephaly, VSD, cleft palate, spina bifida, anorectal malformation, malrotated bowel, club foot and polydactyly. People born with a horseshoe kidney are more likely to also have Wilm's tumor or renal cancer. Two sydromes are associated with horseshoe kidney, Turner Syndrome and Trisomy 18.

Two articles are included here and here for more info. I also found a link to some good pictures of kidney anatomy and abnormalities here, but be warned, it's not for the squeamish. You'll never look at pyelonephrosis the same way again.

I've also been looking at congenital heart defects, but GOOD LORD, it'd take me a week to write all that. Do you have any idea of how many different ways your heart plumbing can be screwed up? It's a wonder and a blessing that most babies are born happy and healthy.