Dysautonomia with Ehler's Danlos Hypermobility type

Hi, I have the situation when ever I exert myself, my core temperature rises, with moderate activity for 5 minutes my temperature rose from 36.9 to 37.3(oral) and continued to rise to 37.6 (oral) and 38.2 (rectal).
If I keep up the activity for 15 minutes, my core temperature rises easily to 38.6, has been known to get to 39.6 when mowing our sloping block. Needless to say it makes me feel seedy, dizzy, headaches, sometimes vomit. I've had overt signs and symptoms of POTS since childhood. I have been increasingly short of breath even with minimal exertion. Had stress echo done which showed insufficient L ventricular relaxation, exercise induced hypertension and tachycardia. I also have episodes of irregular heart beats and the most unbelievably strong abdominal pulse, particularly noticeable on inspiration. Does this make any sense to any one out there???? I'm very heat intolerant, seems to make ANS things worse. I get visual auras, tinnitus, orthostatic hypotension (POTS stuff?). Just getting the EDS diagnosis is a relief, but desperately need help. Thanks for any advice of any one who knows about this, any association with haemochromatosis, and familial, dominant inheritance EDS (type 3 / Hypermobility Type). Many thanks. BeeR70

[Heiferly]

Have you discussed this with your doctor, particularly your dysautonomia specialist?  Hyperthermia is a very serious condition and these temperatures meet the cutoff for hyperthermia:

>38.4–39.9 °C (101–104 °F)

You need to work with your doctors to develop a management plan to keep your temperature in a healthy range and an emergency plan about what to do if your temperature should get over a certain threshold.  There are things such as active or passive cooling vests which can help people with hyperthermia still be comfortable and safe with some limited exposures to environmental heat.  

If you are having these problems with thermoregulation, you should also keep an eye out for hypothermia as it's possible your thermoregulatory system is dysfunctional in both directions.  Your doctor may want to do tests such as a thermoregulatory sweat test [TST] and/or quantitative sudomotor axon reflex testing [QSART] to better pinpoint the source and/or extent of the dysfunction.  

Heat intolerance and exercise intolerance are pretty much a given in POTS; both heat and exercise are basic triggers to the fundamental dysfunction that causes the symptoms of POTS.  Also, the link between EDS/JHS and POTS is well known.  I haven't, however, heard anything about haemochromatosis.  

I'm exhausted and need to lie down, but I'll try to get you links to more information that you may find helpful next time I'm online.  In the meantime, I can't stress enough that you need to work with your doctors to address your issues with hyperthermia.  Hyperthermia can be very high-risk in dysautonomia; until you get this worked out with your physician, please do not expose yourself to high heat or exertion that raises your temperature like that and if you do find your temp. skyrocketing, take immediate measures to cool down or seek emergency medical attention if you can't get it to go down or are alone and there wouldn't be anyone nearby to call for medical help if you suddenly collapsed.

Best,
-Heiferly.