Everything you never wanted to know about kidneys

I wasn't sure if I was going to post about this, but since we've received promising news I figured it's good information.

At our ultrasound last month, it was discovered that our baby had enlarged kidneys. The fancy medical term is renal pelvic dilation. Apparently, this is the most common "anomaly" that is picked up on routine ultrasounds, with about 50% of babies being referred for a follow-up scan.

In the picture above, the gray-colored section inside the kidney is the renal pelvis. It's basically the holding area for fluid in the kidney. When this area is enlarged, it often means that fluid is being retained in the kidney instead of emptying to the bladder. Depending on the cause of the fluid retention, it can cause urinary tract problems in the baby and possibly lead to infection after birth. Detecting the enlargement at 20 weeks does not mean the baby will be born with dilated kidneys, because ultrasound cannot tell us why the kidneys are enlarged, just that they are. We were referred for a follow-up to monitor the size of the kidneys.

In our case, the enlargement in each kidney was the same, which is supposedly promising. That was a sign that even though they were slightly larger than average, it could be completely normal. What you don't want to see are measurements that are significantly different. Anyway, we had our follow-up on Tuesday. We got promising results. The enlarged areas have gotten smaller, which is what they want to see. It is very common for the enlargements to correct themselves as the baby develops, and resolve completely before birth, so this is what we are expecting to happen.

The radiologist recommended another follow-up next month, but I am waiting to hear from my doctor before we schedule it. The current measurements indicate that they are right on the border between "normal" and "mild enlargement." They would be checking to see if they measure completely within the normal range next time. I'm expecting that my doctor will say to skip the follow-up and wait until the baby is born. They would do an ultrasound on her then, and if they are normal we have nothing to worry about. Even if they are still slightly enlarged, it won't necessarily affect her health. There are several options for treatment if needed, but right now we are encouraged by the decrease in size, and it is very likely that it will be resolved before she is born.

Congratulations if you read the whole thing. I warned you that it was more than you ever wanted to know!