Kidney function question

[Unregistered]

This question is, I guess, for Dr. Bruce. My 3rd class medical is up for renewal this month. Last fall I visited my regular doctor three times for flu symptoms. As he always does, he did some bloodwork including something called Standard Metabolic Profile which starting last year now includes serum creatinine. My readings last fall were 1.0, 1.1, and then 1.2 in December. This is in the normal range at that lab but at the very top. Concerned, I made an appointment with a nephrologist team at the local university center. They rechecked my creatinine and did an ultrasound. Creatinine was 1.0 (normal according to their lab), the ultrasound showed no calcifications, a 1.0cm cyst on left kidney, and both kidneys within the normal range of size though on the small side. They calculated a GFR of 85. One of the doctors said my results were "normal", the other said there might be some "smouldering pathology" and to come back for a repeat check in several months to a year.

Is this an issue to the FAA? Am I looking at deferral or denial for this? How to handle on the 8500-8?

 

[bbchien]

No. You still have normal range renal function, albeit at the lower end. If you have a BP above 125/80 you'll get put on Cozaar or the like for pre-hypertension. This has been shown to spare kidney function over the lonnnnggg haul and is a good thing. However, like Judy, you'll then need the initial "hypertension" workup, which is an EKG, Cholesterol/LDL/HDL, Creatinine (which you have), fasting Glucose, and Postassium, plus a letter from your Rxing doc stating your cardiac risk factors and what you are doing to modify them.

This IS NOT a special Issue. If you have all the stuff, any AME can issue. Write me directly at the email address if you need more....

In theory you should not even need the first time hypertension workup...but the problem is that if you don't (If you have a letter saying it was for pre-hypertension), at the next issue we cannot prove your baseline and you're on hypertensive meds....and the workup becomes required then. Best just to get it over with.

 

[huvrluvr]

Dr. Bruce.....there is no mention of ESRD in the disqualifying medical conditions. Will the FAA SI persons on dialysis?

 

[bbchien]

Dr. Bruce.....there is no mention of ESRD in the disqualifying medical conditions. Will the FAA SI persons on dialysis?

Generally they are unwilling beyond a Creatinine of 4 or a BUN of 50. Brain performance really takes a dive beyond those numbers. I can tell you that with chronic ambulatory peritoneal dialysis, the usual Creatinine is 10, BUN 100. With Hemodialysis if the heart can take it, it's more like Cr=8 BUN=75. If you are unusually well dialyzed and this is characteristic of your weekly performance, you might have a chance. But it's very unlikely.

Think of you body making about one gram of Creatinine per day. There's 1440 minutes in a day, so it's clearing ~1.5gm/1440 or 100 mgs/minute. If your concentration in the blood is 1 mg/ml, this is equivalent to a "creatinine Clearance of 100 ml/minute. If it's 1.5 mg/ml that's only 66 ml/minute of kidney clearance. If it's 2.0 mg/ml that's 50 ml/minute. If it's 4.0 mg/ml that's about 25 ml of clearance per minute. All your problems begin about there.

Note, if you are small (Creatinine comes from muscle) you might only make 1.0gm of creatinine per day. You get different numbers from this.

A Creatinine of 1.2 generally reflects about 75-100% of renal function depending on your size and muscle mass. But this is a normal performance range. FAA gets concerned around a Creatinine of 1.8 to 2.0. That's why "prehypertension" antihypertensives are generally thought to be a good idea- it slows the progression.