My blood potassium has varied from 3.5 to 4.3 (ref. 3.3-4.8) from 2007 to 2013 (21 meauserements, mean 3.76).
During the same time, my blood sodium has been 140-147 (the upper reference limit varies a little, 144-145, lower limit is 137) (28 measurements, mean 142).Thus potassium has always been normal but sodium sometimes over normal.
A water deprivatiion test (without NaCl infusion and without ADH) was done in April 2009. From eigth o'clock to eleven, antidiuretic hormone (ADH) decreased from 2.5 to 1.7, and S-Osmol was 295 and 293, respectively. U-Osmol increased from 553 to 645. Plasma sodium was 145 at both times (ref. 137-145). I was not thirsty. Previously, in February, same year, ADH was 0.7 and sodium 146, In March sodium was 147 (ref 137-144). At all times S-Osmol has been over 290. I often feel like dehydrated.
Later, on May 31 2013, S-Osmol was 295, morning U-Osmol 632, P-Na 142, P-copetin 1.5 (ref. 1.5-2.8). Copeptin is a marker for vasopressin (ADH).
June 2 2013, morning (1-hour) U-Osmol 387, ionized Ca 1.37! (ref. 1.16-1.3).
A doctor said that I may have slight hypothalamic diabetes insipidus. Not feeling thirsty disputes it. The doctor said that I should keep a bladder diary about daily water intake and urine amount. I have done it for two days. The result seemed to be normal. But because the disorder is episodic or periodical, I cannot know when it will begin again. I am waiting for a longer period to keep the diady. Previously my daily urine amounts measured have varied between 2700 and 4225 ml.
I dont know whether true diabetes insipidus can be periodic. And whether blood calcium vary much? My latest ionised Ca was 1.37. Could it someteimes be even higher?. Hypercalcemia may cause polyuria. A doctor said that it would be difficult to find a surgeon who would do hyperparathyroid operation as to my ionized Ca values (varying 1.29-1.37). I may have parathyroid hypelplasia (according to a Sestamibi Technetium scan).
What other things can cause variation in my symptoms? Dysautonomia? Possible adrenal insuffciency? I must note that my fasting blood glucose has been norml. Now I am testing how thyroid medication affects my water balance. I have decreased my thyroid Medication (Erfa Thyroid) last time early in this year. I have been either on 2 or 2.25G instead of previous 2.5. I think that the dose difference between 2.0 and 2.5 is very small. it is difficult to break a tablet into quarters, However, it seems that on 2,25 I gain water, and on 2G I sometimes loose water. This is contradictory to what is known about hyper or hypothyroidism. I must gather additional testing results.
There is another variable, namely how much I execise. I think that much hard exercise causes nocturia. Could it be due to heart or kidney problems? I sometimes work hard in our garden.
No sodium or potassium issues.
Were you tested for DI?
Many symptoms of adrenal insufficiency.....