Dr. Cranquis' Mumbled Gripes

30somethingcrisis submitted:

I missed the open Cranquis-Mail inbox the last go-around, so I’m glad I won! 

I have a question regarding being a living kidney donor. Someone I know is currently on dialysis awaiting a kidney transplant. I do not know thatI am compatible, and before I would even broach the subject with them, I would want to know if it would even be medically advisable for me to donate.  Is it a contraindication to donate a kidney if you are on Metformin for PCOS? I have scoured the National Kidney Foundation’s Living Donor website, and found that those who are taking Metformin for diabetes can’t donate, but that is due to the diabetes, not the medication. I can’t find anything related to PCOS and Metformin. I know the if you have kidney issues, doctors generally won’t prescribe it to you. My kidney function is obviously good right now, but would having one less kidney possibly impede function enough that I would need to be taken off Metformin? Currently this is working very well to control my PCOS symptoms, so I would rather not do something to necessitate changing or stopping my current treatment plan.

Well congratulations on winning the first-ever Fast Lane Cranquis-Mail reply by participating in the Facebook Fan Page Weekly Theme contest! Your question gets jumped to the head of the line. Here’s my reply:

It’s nice to hear from you again, and I’m glad the metformin is helping your PolyCystic Ovary Syndrome (PCOS) symptoms. You obviously did a lot of “scouring” of the NKF’s website, because I couldn’t find any specific mention there about metformin + kidney donor qualifications. But I did read that even donors with diabetes can still be considered for kidney donation, depending on a number of factors. So I don’t see why metformin use alone would exclude you from being a living kidney donor!

In short: as a lowly Urgent Care doc, I honestly can’t say whether you are “medically qualified” to donate, but Living Donor programs often have a screening questionnaire which can help figure that out. You should contact your friend’s Kidney Transplant Coordinator and ask for a “donor screening questionnaire” (no need to even mention the specific patient/friend you’re referring to yet!), and go from there.

As for “would having only 1 kidney make me less able to tolerate metformin?” — Well, doctors usually avoid giving metformin to patients with low creatinine clearance, which is a calculated measurement of kidney function. Does the creatinine clearance drop significantly in people who have donated a kidney? This 2006 article from a Nephrology journal hems and haws a bit, but appears to indicate that various studies have not shown significant impact on renal function in living kidney donors (Try slogging through the “Summary of Risk Factors: Renal Failure” for more details.)

So, this URGENT CARE doctor’s opinion is: you’d probably still be able to take metformin after donating. But again, this is an excellent question to ask the transplant team. I hope everything works out for both you and your friend! :)

***Pending Cranquis-Mails: 10; Inbox: Closed***