July 21, 2004
Question from Virginia, USA:
This is a follow up question to my previous question. My endocrinologist did a 24 hour urine test for magnesium, which turned out high and, since blood studies on the other electrolytes were normal at the time of the test, just figured I had a simple magnesium leak. Well, my potassium dropped several more times in spite of taking supplements. I don't understand all the mechanisms/interactions of diabetes, electrolytes, and the kidneys. It doesn't seem to be a problem in other type 1s I know whose control is far worse then mine. I figured it wouldn't hurt to know if anything else was leaking so, I saw a nephrologist who did a 24 hr urine on everything, blood cortisol and blood aldosterone, a regular blood panel and an ABG (arterial blood gas). The following were the results: 24 hr urine Calcium - high Magnesium - high Potassium - normal Sodium - normal Creatinine - albumin normal Blood Aldosterone - normal Cortisol evening - high potassium - mildly low, 3.4 Magnesium - low 1.0 Calcium - normal Sodium - normal ABG - pH 7.47 high, CO2 - 3.4 low PO2, Bicarbonate, Base excess, Total Hemoglobin, Carboxyhemoglobin, Methemoglobin, Total Oxygen, FiO2, normal; Catecholamines, (urine total) epinephrine (adrenalin), Norephinephrine (noradrenaline), dopamine normal The nephrologist said it is indeed some type of familial kidney leak, although, not Bartter�s syndrome because of the normal aldosterone, and not Gitelman�s syndrome because of the normal sodium plus elevated calcium excretion. Is high cortisol something that should be followed up on or is it just normal in a magnesium/calcium leak? I've never taken steroids in my life! Are there any other hormones that might play into this? Does elevated cortisol play havoc with blood sugars certain parts of the day, such as night to early morning, including a very strong dawn phenomenon or Somogyi phenomenon? Or, would it be consistent? Would the fact that the normal 24 hour urine by products of hormones (epinephrine, adrenaline) make the blood cortisol reading more likely not a result of stress? Does being very high (350 mg/dl [19.4 mmol/L] or more) stimulate the release of blood pressure raising hormones? My blood pressure is normal, (usually around 120/65) but I've noticed it will sometimes elevate to the 140/80's range when my blood sugar is high. I appear to be the only one even mildly concerned over all this, my primary care physician tells me to see the endocrinologist; my endocrinologist tells me its not that big a deal as long as I keep taking supplements, and the nephrologist diagnoses me with something weird and refers me back to my endocrinologist. I'm feeling really lost here. Can you recommend any resources or texts that deal with both diabetes and a co-existing condition that makes electrolyte control difficult?
I have reviewed your results. However, there are no numbers associated with them. Therefore, when you indicate the cortisol is high in the evening blood, this may or may not be a big deal. Generally, cortisol levels are measured when a physician suspects that elevated cortisol levels may be the cause of a condition called Cushing’s syndrome. This condition is important to identify in individuals with diabetes because it can be a secondary cause for elevated blood sugars and blood pressure. However, an evening blood cortisol is not the definitive measurement for this condition. Your endocrinologist would be in the best position to answer this questions. I would suggest that you not get too worked up over some of these relatively mild issues. This issues related to the measurement of hormones can best be answered by your endocrinologist. However, I would suggest they would only be issues if the results were really high.