Thyroid abnormalities and perimenopausal symptoms are the commonest cause for this.
In your case, Thyroid levels are all normal so that is ruled out. But perimenopausal still remains a possibility. Normal Estradiol levels of course makes it less likely, but normal estradiol does not rule out perimenopause completely. Night sweats are a very typical symptom of perimenopause. The exact nature of the sweating episode is not at all significant, there can be wide individual variations.
Besides these two causes, the other causes which you need to rule out are:
syndrome : This is a possibility for you. Carcinoid tumours developing in the intestine may cause this. You have to do tests like HIAA.
* Medullary tumours of the thyroid: This is again a possibility. You have to do thyroid function tests and ultrasound of thyroid, etc.
* Mastocytoses: These are rarer causes. Mastocytes are benign cells of the connective tissue. Growths of these are to be rued out.
: This is usually accompanied by other symptoms, still must be ruled out.
* Drugs: Certain drugs can cause this. Check with your doctor if you are taking any drugs.
* Food: MSG, in Chinese food, is well known for this. You will also have to observe whether you have started any new foods which might be the cause.
Discuss all these causes with your doctor. They are rarer causes and not necessarily significant for you. Still you must discuss with your doctor so that you get an informed discussion.
Hope this shows you the way forward - wish you good health and a quick recovery.
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