"mis"-diagnosis Of Diabetes Insipidus?

[firewatcher]

Greetings all, I have a question that I can not find the answer to: Why is diabetes insipidus frequently a misdiagnosis? Frequent urination is common for both disorders, but DI is a vasopressin (ADH) deficiency and POTS has other etiology. Does the frequent urination of POTS also have the plasma/urine osmolalities that are seen in DI (high plasma Osm/low urine Osm)? Or is the misdiagnosis based on frequency and quantity alone? Do they overlap? How do you know that it is NOT DI? If any of you know, please tell me or point me to some medical journal articles. Thanks a bunch! I am in the process of my third "dehydration" test and feel like a raisin!

[DancingLight]

This is a good question and I hope someone will have the answer.

I don't know what the reason is for all the overlap or how many of us have both conditions.

I was diagnosed with 'partial diabetes insipidus' but i don't think that the test was done properly. I don't know what to think.

My POTS doc hasn't pushed it, and he seems quite puzzled by my level of urinary frequency and volume, despite his level of expertise!

I take DDAVP twice a day and I'm not sure how I would manage without.

The problem is that when it wears off I pee and pee and pee even more in between doses.

Dr. Grubb put me on a night time dose the first time I saw him and later I added in a day time dose.

I have heard other folks say that it is not okay to take DDAVP regularly like this, and that Vandy recommends not taking it more than 2x per week.

I feel very confused about what decision to make or even what sort of doctor is the right person to see about this problem. However, it significantly interferes with my sleep and quality of life.

Emily

[Kitsakatsa]

I had a misdi of DI purely because of input/output alone. I was malnourished and dehydrated and my MD's first task (I was undiagnosed) was to pump in everything. In which case, everything came out to the exact measure. This has been a problem with retaining sodium. We've noticed that is almost contra to administer IV because I lose my sodium like gang busters. Hypertonic is good short term but has a talent of pulling even more intracellular water extracellular and into output.

My concern is late vision problems with POTS patients. If DI causes these, surely we need to watch out for them. The shuffling of water can damage (possibly?) the small capillaries in the eye similar to diabetes flush?

[anna]

Oh yes please someone point me in the direction of some good medical data on this. I and my 3 children have fluid retention problems but we all seem to have diffrent problems!!

I have high BP to low but also very big HR jump on standing I pee lots even if I do not drink anything. My daughter has normal to low BP with high HR on standing etc. pee's like me. Then one son Normal to very low BP and high HR on standing drinks little pee's at 'normal' times but pee's loads when he goes, (he is Autistic and has problems with knowing when he is thirsty or needs to go to pee). Then other son has the low BP high HR etc, had very bad problems a while back with peeing about 5 times an hour all day long (ok when laying done at night though!) but also has had some very high blood sodium readings, he has been checked for DI after 7 hours he managed to consuntrat his pee enough to stop test! now waiting to see endo. as paed. not sure what is going on.

I am at the moment salt loading for my D. and one of my boys as told to by there cardiologist and cutting salt right out for my other lad as told to by his paed. it is quite odd and I want to get to the bottom of all this.

Anna

[firewatcher]

"trying to catch the deluge in a paper cup..." I can't hear that Crowded House (80's rock group, I know, I'm dating myself) without thinking of all this. THe snippets of info that I can find are that with POTS it is a blunted ADH response, but the constant urination is due to several possibilities:

-a reset osmostat (the thing that controls how much water you keep and how thick your blood is.)

-idiopathic hypovolemia (your body truly believes that you keep too much water and wants you to be several quarts (3 liters usually) low.

-the renin-aldosterone paradox (you don't make enough of either to hold onto enough sodium to stop urinating)[Circulation 2005, Raj, Biaggioni, Yamhure, Black, Paranjape, Byrne, and Robertson...google it]

With DI it is purely an ADH thing, either your brain does not make enough or your kidneys don't respond to it.

Now plasma and urine osmolalities (the concentration of "stuff" in with either liquid) are obvious with DI, the plasma osm is high and the urine osm is low (pee is very light or clear) and you don't make enough of the hormone ADH to retain water (central DI) or your kidneys won't respond to it (nephrogenic DI.)

The crux of the question is this, did any of you whom were MIS-diagnosed with DI do a water deprivation test? Were your plasma and urine osmolalities out of whack?

"Something" happened to me in November that is causing me to urinate more than I take in (64 oz. in and 80 oz. out) and my osmolalities are indicative of the central form of DI. If I go off the dDAVP my hematocrit (concentration of red blood cells in plasma) goes way up. I also have a "dump" once it quits working (talk about running to the bathroom!) My first endo and nephrologist (kidney Dr.) looked at all this and said "Aha! Central DI!" But is it?

Do any of you have any further information? I have called, faxed and emailed Vanderbilt (I have an appointment with them in November) but I lack the super-secret doctor decoder ring to get a straight answer, actually any answer.

Meanwhile I have come off my meds slowly and have been dehydrating just as slowly and will do MORE tests...I feel like a tortured raisin.

[LindaJoy]

I am currently seeing a nephrologist to determine if I have DI. He said it's a possibility. I had a three-hour water deprivation test a few weeks ago, which showed my urine concentrating after three hours. My endo at Cleveland Clinic said I don't have DI if my urine can concentrate like this, even after just a short time. The nephrologist isn't quite so sure.

There's an article that was sent to my by a woman who belongs to a DI support group that mentions the connection between Dysautonomia and DI. It's found at http://en.wikipedia.org/wiki/Dysautonomia. The pertinent section reads, "In some cases...the kidney may fail to properly retain water (diabetes insipidus)."

I know that my urine osmolality has been very low at times, so this is a red flag to my nephrologist, as are my pituitary issues that I've had for years (tumor, high prolactin, low vasopressin, breast lactation without pregnancy). I'll be doing another water deprivation test soon. Not looking forward to it.

Take care, everyone.

Linda

[firewatcher]

I too have unexplained galactorrhea (milk discharge) but I never have had pituitary "issues." I have really low LH and FsH, that is almost like perimenopause in it's symptoms. My neph and first endo say it's partial DI, but my new endo is not so sure.

[anna]

ok one of my boys had a water depravation test, his results were:-

8:30 urine Na 62 K 41.9 Creat 8.0 Osmo 468

9.30 Blood Na 143 K 4.8 Creat 49 Urea 3.5 Osmo 297

10:00 Urine Na 60 K 35.2 Creat 2.5 Osmo 273

11:00 Blood Na 143 K 4.6 Creat 53 Osmo 290

11:00 Urine Na 74 K 48.4 Creat 3.0 Osmo 320

12:00 Urine Na 112 K 71.8 Creat 6.1 Osmo 504

13:00 Blood Na 145 K 4.4 Creat 49 Osmo 292

13:00 Urine Na 167 K 72.2 Creat 8.6 Osmo 610

14: 00 Urine Na - K- Creat- Osmo 703

15:00 Blood Na 144 K 4.5 Creat 48 Osmo 287

15:00 Urine Na 224 K 67.7 Creat 10.4 Osmo 706

16:00 Blood Na 144 K 4.6 Creat 48 Osmo 290

16:00 Urine Na 236 K 64.2 Creat 8.6 Osmo 705

Does any one have any ideas what this means we have been told son does not have DI as he was able to consintrate his urine.

Anna

[jump]

I can't shed any light on the matter, but did want to chime in and say this has been a problem for me, too.

In fact, the excessive thirst and the constant need to pee were my first complaints to the doctor; the funny heart rates didn't bother me in my day-to-day life nearly as much as the thirst. The thirst for me is actually painful at times, and I can never sleep more than an hour or two at time because I need to wake up and use the bathroom.

Originally, a nurse-practitioner I was seeing said she thought, just based on my input/output, that I must have DI. But when I saw my PCP about it, she said there was no way I could have DI because it's so rare. No one ever offered me any tests at all, even though routine urine tests always come back with a low spec gravity.

When I was diagnosed with POTS I felt really relieved that polyuria and polydypsia are both symptoms, because I felt like, thank god, I'm not crazy after all!! People used to get angry with me that I NEEDED to drink so much and use the bathroom so often (doesn't make car trips fun!) but now that I have a reason for it - albeit an unclear one - my friends and family are much kinder about it.

jump

[flop]

08:30 urine Na 62 K 41.9 Creat 8.0 Osmo 468

10:00 Urine Na 60 K 35.2 Creat 2.5 Osmo 273

11:00 Urine Na 74 K 48.4 Creat 3.0 Osmo 320

12:00 Urine Na 112 K 71.8 Creat 6.1 Osmo 504

13:00 Urine Na 167 K 72.2 Creat 8.6 Osmo 610

14: 00 Urine Na - K- Creat- Osmo 703

15:00 Urine Na 224 K 67.7 Creat 10.4 Osmo 706

16:00 Urine Na 236 K 64.2 Creat 8.6 Osmo 705

09.30 Blood Na 143 K 4.8 Creat 49 Osmo 297

11:00 Blood Na 143 K 4.6 Creat 53 Osmo 290

13:00 Blood Na 145 K 4.4 Creat 49 Osmo 292

15:00 Blood Na 144 K 4.5 Creat 48 Osmo 287

16:00 Blood Na 144 K 4.6 Creat 48 Osmo 290

Hi Anna, to make interpreting the results easier I have split them up into urine and blood results separately. First of all to translate the abbreviations (sorry if I am teaching you to suck eggs but medics do have a wonderful way of writing everything in gobbledegook!).

Na = Sodium K= Potassium Creat = creatinine, a waste product from protein breakdown.

Osmo = Osmolality (not quite the same as osmolarity)

Looking first of all at the blood results, his are within the normal range and as the water deprivation test went on they stayed the same. This means that the body retained enough water to prevent him from getting dehydrated. In someone with diabetes insipidus all four values would get higher as the blood got more concentrated from loss of water.

The urine results are slightly skewed by a raised osmolality in the morning sample but that is probably because overnight the kidneys concentrate the urine more to enable healthy people to sleep without needing to get up to pee all the time. Ignoring the first osmo reading, the others all show the urine becoming more concentrated as the test progresses (high osmo readings mean that there is less water mixed with the molecules in the urine, low osmo means lots of water diluting the urine). When his body was denied water to drink it will have secreted ADH (anti-diuretic hormone) to ensure that his body preserved the water that it needed by reabsorbing water back from the urine in the kidneys.

The steadily rising levels of sodium and potassium in the urine also show that the urine is becoming more concentrated. The kidneys are probably excreting the salts at a fairly constant rate but because there is less water mixed with them the concentrations go up (i.e. the mg/hour will be the same but the mg/litre will go up). I couldn?t find any info on urine creatinine so can?t shed any light on that specific part. To me this appears to be a normal physiological response to water deprivation and would not fit with a diagnosis of diabetes insipidus.

In diabetes insipidus you would expect the urine osmolality to remain low (i.e. the urine is still dilute and pale coloured) but the blood tests to show evidence of dehydration ?the blood Na, K, Creat and osmolality would all increase. The body still pees out lots of water even though the body is dehydrated and needs to retain that water it is unable to do so.

I hope that makes sense, I have just tried to apply some high school biology and chemistry to the values you gave.

Flop

Edited July 9, 2008 by flop
bother - can't get the results to stay in tidy columns to make them easier to read!

[anna]

Flop,

Thank you very much, that makes things much clearer to me. My son's paed. is a good Dr. but tends not to explain things just gives us the bare info.

Sons paed. is a little concerned about the peeing thing as my lad has had some raised blood sodium levels at 147 and his base sodium is within normal range but a little on the higher end at 145 this is what has got the paed. thinking there might be some endo stuff going on to add to this he has had bouts of gut ulcers and other stuff going on.

Thanks again flop.

Anna

[firewatcher]

I am soooo sick of this "PRACTICE" of medicine, when do we get to the performance? I just saw my endo, who now says that it is NOT partial DI, but he's not sure...He wants me to see another, older endo to make sure (#3). Apparently after 4 days of water restriction of less than 50 ounces a day (many grey-outs, tachycardia and a loss of 4 pounds) and a 12 hour fluid restriction, I concentrated my urine to 760. I don't understand why he won't just do the water deprivation test with an ADH assay. This is insane. He has at least OK'd me to go back on the dDAVP, but at half a dose. This next endo can't see me till the week before my Vanderbilt visit in November and I am wondering if there is any point. Half my labs say DI and one says no, so I am still swinging at the end of my rope till November. AAaaaarrrrrgh!

[firewatcher]

Revisiting the DI diagnosis again...Yesterday I saw yet another Endo, this time the grand, high, muckety-muck, head of the department doc. He says that I do not have DI. THis was his medical reasoning: because my electrolytes (sodium, potassium, etc.) are not out of whack unless I am on dDAVP, AND because I managed to concentrate my urine after 6 days of fluid restriction (less than 2 liters fluid intake a day,) I am producing vasopressin...therefore I do not have DI. He did not know much about POTS, actually nothing, and had not ever heard of someone's heart rate jumping like that. He thinks that whatever mechanism in the ANS dysfunction that causes the frequent urination, is causing mine. Just like me, he is eagerly awaiting an explanation from Vanderbilt in November. (Very nice doc, by the way, he spent over two hours with me until after 5pm! Highly recommend this one if you need an Atlanta Endocrinologist.)

[ajw4790]

Sounds like you had a good appmt. and that he knew overall what he was talking about. That can be refreshing! And it sounds ike overall it was good news as well. I hope you are able to find help now for your symptoms that the diagnosis has been cleared up somewhat.

[pat57]

Postural Orthostatic Tachycardia Syndrome (POTS)

* Frequent urination - Frequent urination is a common symptom of POTS. This problem is sometimes misdiagnosed as diabetes insipidus, which is a disease caused by the reduced production of a pituitary hormone called vasopressin.

http://www.steadyhealth.com/articles/Postu...TS__a81_f0.html

I came across that and thought you might like to see it.

[firewatcher]

Thanks,

I showed that article with that quote highlighted to every doc that mentioned DI. That was how I got to the top of the food-chain doc. No one knew the answer to whether it WAS DI or was NOT DI, and it seemed like all the docs were plucking daisy petals (she's got DI, she doesn't have DI, she's got DI, she doesn't have DI, she's got......) I thought it would be an easy question, but apparently it is not. I do intend to ask point blank when I get to Vandy, so that I have a definitive answer to give you all. IF it WAS DI, I would be looking at a whole other system and autoimmune endocrine failure which could be treated and possibly reversed if it was caught in time, if it is NOT DI then it is POTS and works on a whole different system. And on and on it goes.

[pat57]

Well, my pc is going bonker's but melissa Kaplen could probably help you. Read her stuff.

http://www.anapsid.org/cnd/index.html

there is a link on that page to chronic neuroimmune diseases and "somewhere" a place to report bad links. If you hold your cursor over that it will show her e-mail address on your lower browser (if that's what it's called)

Looks like she as been through what you are going through.

bye bye! I can't wait for this PC to load- gonna have to stay off or fix it..................later.

http://thyroid.about.com/cs/doctors/a/topdocs.htm

[dlark]

Firewatcher,

I have central partial diabetes insipidus, orthostatic intolerance (specifically Low-flow POTs), Chronic Fatigue Syndrome (CFS) and a partially empty sella. I do believe there is an overlap within these conditions and there is some interrelation. For instance Chronic Fatigue Syndrome (CFS) is often accompanied with orthostatic intolerance. Also low blood volume falls in there somewhere and problems with ADH being shut down. If you want to read more information on this go to the Lyndonville news archives http://www.pediatricnetwork.org/lyndonvillenews/index.htm , and select articles such as July 1999: Relationship Between Neurally Mediated Hypotension and CFS , July 1999: Circulating Blood Volume , March 2000: Evaluating Blood Volume Studies - Some Thoughts, May 2000: Orthostatic Intolerance: An Introduction . These articles are written by Dr. David Bell, a well known and well respected CFS specialist.

As for my diagnoses of partial central diabetes insipidus, it was not a clear cut textbook case nor was it easy to come by. Prior to the DI diagnosis and DDAVP tabs, I was drinking 6-8QTs water daily, always thirsty, and constantly using the bathroom. Without my water, headaches and lightheadness were worse etc. as well as my irritability. My excessive drinking started in October 2004 if not before and it wasn?t until the summer 2007 that a diagnosis of partial diabetes insipidus was made and I started taking DDAVP tabs. In February 2007, I had an initial consultation with Dr. Bell. He suspected diabetes insipidus and recommended to my doctors that I have a water deprivation test. He also recommended other testing such as a total circulating blood volume test by the Cr-51 method.

In April 2007, I had a water deprivation test. Although the endocrinologist?s office who preformed this water deprivation test told me it was normal, it was not. After being cut off from food and liquids including water since the night before, my serum vassopressin (ADH) levels both at 8:18AM and 1:21PM the day of the test were <0.5 pg/mL. 0.5 pg/mL is the limit of detection at the lab where the tests were preformed. I had some ability to concentrate my urine. In June 2007, I had my pediatric endocrinologist review the water deprivation results and he ordered from a different lab additional serum and urine osmolalities and serum ADH after overnight fast from food and liquids including water since ~7:30PM. The results from samples collected around 9:50AM were ADH was <0.8 pg/mL (ref. interval 0.0-4.7), my serum osmolality was 295 mOsmol/kg (ref. Interval 275-295) and my urine osmolality was 396 mOsmol/kg (ref interval reads After 12hr fluid restriction: >850). At this lab for ADH the limit of detection is 0.8 pg/mL. I had had a 14 hours + of no fluids and food , my urine osmolality was low.

In April 2007, I also had my first total circulating blood volume test by the Cr-51 method. My plasma volume was decreased at 21.4 ml/kg (Normal 30-45 ml/kg). The Cr-51 blood volume results really added to the picture and made things clearer that I had problems related to conserving and holding onto water and it made sense that a the lack of sufficient ADH played a role.

Since July 2007, I?ve been taking DDAVP tablets and since April 2008, I?ve also been on Florinef (fludrocortisone) tablets. Overall these medications have been helpful and made life a little easier. Initially, getting used to DDAVP and adjusting to it was not easy and took some time. At this point on the DDAVP and Florinef, I?m drinking about 2QTs water per a day. I?ve had additional Cr-51 blood volume testing now (I believe I have 3 sets of results now) and my plasma volume is still low (19.5 ml/kg on 8/2008) and we are still trying to work on increasing my plasma volume.

Since my medical history is quite extensive and the results numerous, I?ll stop here for now. If you have any questions, please post and I?ll do my best to answer them. Hope this information is helpful and I hope you get some explanations and answers from Vanderbilt.

[firewatcher]

dlark,

Thanks for the links! I had read most of those before and they are why I am suspecting low blood volume as well ( a pulse pressure of 7 should give you a clue!) I also had an ADH of <0.8 with a serum Osm of 295. The last SOsm/UOsm I had done was 295/354 and that was after 13 hours fluid deprivation. I feel soooo much better on the dDAVP, but the two second opinion docs want me off it until I get back from Vandy. I don't know how many times I'll have to stop before I get there, it's a six hour drive. I know that POTS can cause something that mimics Central DI, and I hope to know the exact difference soon. I know I have always had the HR symptoms, but the constant urination is new since this time last year. I just want to make sure that the docs aren't dismissing an undiagnosed autoimmune thing.

Welcome to the forum by the way. I have rarely come across a more positive group of people and I am glad to be a part of it!

[firewatcher]

OK, Dr. Biaggioni said that while POTS patients had polyuria, they could concentrate their urine after 12 hours of fluid deprivation. The Serum Osmolalities and Urine Osmolalities are essentially normal with POTS, it's a renin thing that caused the urination, NOT an ADH thing. After looking at my SOsm/UOsm results, they are not typical for POTS but are for Partial Central Diabetes Insipidus. He also stated that this was not his point of specialty, and that ONLY a clinical water deprivation test would give a definitive diagnosis. But, that was unnecessary with me since the treatment would be the same regardless of either diagnosis. He also did not believe that POTS could cause clinical DI.

So, the MIS-diagnosis is based on volumes of urine, NOT osmolalities. From my readings though, if you consume large quantities of liquid for any length of time, you can "wash out" the concentrating ability of your kidneys, so the Urine Osm will be low, there must be a corresponding HIGH Serum Osm for it to be DI.

[Sophia3]

dlark

thanks for your input with DDAVP. we never did the water deprivation test but my endocrinologist suggest I have a partial case after DDAVP samples helped me IMMENSELY not to urinate every 10-20 minutes.

DDAVP has not helped me feel better but i can drink and hold in fluids which helps a lot.

firewatcher, interesting what vandy said...we have checked my pituitary function a few times and I personally feel my issue is related to that gland even though 'mosts' test have been normal, others were not but it's been years. And DDAVP is a godsend.

[firewatcher]

This one is for Serbo, maybe it will help.

[Serbo]

Thanks!

[Serbo]

Just a bump for this thread.

Off to see my Endo on Tuesday as DDAVP seems to have stopped working for me. Only cause i can think of for it is reintroduction of gluten and dairy in to body. Today had a load of goats cheese, followed by big allergic reaction for me and DDAVP still isn't working.

Does anyone else have days or a few days in a row where they need an extra dose or so of DDAVP? Endo says this is normal, but i hate not knowing why DDAVP decides to stop working on some days.

I googled DDAVP stopped working. Seems some people find the change in seasons can be enough to make them need an extra dose.

[Dizzysillyak]

Hi serbo,

I could be wrong but I thought mack's mom answered this question on the gluten free thread.

She said that our bodies leak fluid when we come into contact with an allergen. I would think this would include increased urination for some. Our bodies are trying to clean itself ..

at least that's the way I understand it. My nose and throat drain like a leaky faucet if I come into

contact with an allergen. This was 10000 times worse when I was eating gluten, dairy, soy, etc.

Tc .. D