Bex

Forgive me for my ignorance on this, but I could do with a bit of advice regarding whether a recent change in my symptoms is related to POTS. I was diagnosed with POTS three years ago, but I've had other problems related to EDS that have been more of a problem for me. I suppose you could say my experience of POTS has been quite mild - difficulty standing for any period of time, but not much other than this. However, I seem to have had a sudden change in symptoms over the last few days. I feel more lightheaded, more breathless (shortness of breath has always been my first 'warning symptom'), dizzy in a vertigo-type way, shaky and weak. I've also had dry eyes on and off during this time. I took my blood pressure just to see if that might have anything to do with it. It's been a little variable, but at its lowest it was 98/51 (whilst sitting). It always used to be no less than about 110/65. Has anyone else experienced a sustained drop in blood pressure like this, and is this something expected with POTS? I've always thought about blood pressure being fairly independent of POTS - am I wrong about this? Many thanks Bex

Hi Sue I'm a trainee clinical biochemist working in a pathology lab in the UK, so hopefully I will be able to give you some clues on what your results mean. We have different reference ranges and work in different units over here, but based on the ranges you have given I should be able to figure it out. Your results look perfectly normal to me. I'm not sure exactly what you mean when you say you had some odd serum cortisol results in the past, but these results (urine, serum and saliva) are all within the reference ranges you have given. A person with Cushing's syndrome will usually have markedly abnormal results in at least one of these tests. No one test is 100% sensitive and specific for the diagnosis of Cushing's, so a combination of tests is usually required. A dexamethasone suppression test is usually one of the typical tests requested to rule out Cushing's. If you are particularly worried, I would suggest you have one of these done. However, I am almost 100% certain this would come back as normal. As for your reference to the relationship between ACTH and cortisol, ACTH is released by the pituitary under the influence of CRH, which is released by the hypothalamus. ACTH drives the synthesis of cortisol in the adrenal glands. Cortisol has a negative feedback effect on the synthesis of ACTH, so you are right in saying that (in a healthy individual) if cortisol is high, ACTH should be low. However, if ACTH is high, it is not necessarily the case that cortisol should be low. Cushing's DISEASE is caused by a pituitary tumour which secretes ACTH. This drives the adrenal glands to produce more and more cortisol - therefore, in this case both ACTH and cortisol will be high. Cushing's SYNDROME is used to refer to any condition which increases the concentration of cortisol in the bloodstream (this can also, confusingly, refer to Cushing's DISEASE). Cushing's syndrome not caused by a pituitary tumour (i.e. not Cushing's DISEASE) can refer to adrenal tumours which secrete cortisol, adrenal hyperplasia, or other tumours which secrete ACTH (known as ectopic ACTH). In these cases (adrenal tumour, hyperplasia or ectopic ACTH), cortisol will be high, but due to the negative feedback effect of cortisol on the synthesis of ACTH, ACTH will be low. I hope this has clarified your understanding of cortisol and ACTH, and therefore the relevance of your results. In interpretation of cortisol results (especially serum cortisol), you have to remember that the concentration is very variable, and depends on many factors, such as how stressed you are at the time of sampling. Also, when considering a diagnosis of Cushing's, you should also remember that depression, obesity and alcohol can give results that point to Cushing's - this is known as "pseudo-Cushing's". Hope this has helped Bex

Thank you for all of your replies - they were really helpful. I honestly thought I was either imagining it or I was having something random and unexplained that nobody had come across before! It's reassuring to hear that it's likely to be nothing serious, and hopefully not something else to add to the list of health issues! What you describe sounds spot on, Libby. I get the feeling of needing to clear my chest during the episodes, but can't. It's very bizarre. I've not been tested for MVP, but I seem to remember hearing at some point that it's relatively common in EDS, so I wouldn't be too surprised if I did have it. It was something I was planning on asking about at my next appointment with the autonomic specialist, so I think I will definitely mention it now. Thank you all also for welcoming me to the forum

Hi everyone, I have POTS as a result of EDS 3, plus other complications (bowel, bladder etc) that have been put down to the same condition (EDS interlinking with dysautonomia). Lately I've had something else happen, which is quite strange, and I wondered if anyone else had experienced anything similar. Every once in a while I get a very pronounced fluttering feeling in my chest (presumably an arrhythmia), and at the same time I can't seem to be able to inhale or exhale. It's like my chest is paralysed whilst I feel the fluttering. Luckily the feeling is only momentary, so it hasn't caused any major issues, but it's slightly concerning. I wondered if it might be part of the dysautonomia etc, but it seems a little odd. I have a feeling I may be unique with this symptom! I'd be interested in hearing any thoughts or similar experiences any of you have had. Thanks Bex

Just thought I would add a few bits of info to this thread. I'm a clinical biochemist, and work in the labs that process vitamin D tests. I haven't read the article, but I will say that vitamin D is a very hot topic at the moment, and there are a lot of conflicting studies and published articles out there. There are also real discrepancies regarding what is considered as a low, healthy or high vitamin D level. What I'm trying to say is that I wouldn't personally focus too much on vitamin D. Statistics show that almost everyone in the UK over the winter months is considered to be deficient in vitamin D. A low vitamin D level is therefore not particularly indicative of anything, except low sun exposure. It is also important to remember that a person can have too much vitamin D. We see cases of vitamin D toxicity, where a person has taken too many supplements. This can cause far more problems than a deficiency.