Subtitle: You have nothing to lose but your goitres!
So here's the strange thing: I have a TSHoma - a pituitary tumour which secretes TSH (thyroid stimulating hormone). It's super rare. According to my endocrinologist there are maybe thirteen or so other people in the UK with this condition which, in a population of 63 million, is Not Very Many, although it probably does go largely underdiagnosed; I had my first symptoms when I was around 16 or 17 and didn't get a diagnosis until I was 22.
But anyway, the point is that it can sometimes almost feel like two separate conditions; I have the pituitary adenoma, and the hyperthyroidism it causes. My symptoms, apart from the odd nasty headache, are pretty much exclusively those of hyperthyroidism; my treatment is for the adenoma. Consequently, although I am in all seriousness a paid-up member of the Pituitary Foundation and can chat about transsphenoidal surgery and lanreotide injections with the best of them, I'm missing out on the chance to bitch and moan about sinus tachycardia and getting the shakes with other people whose blood has turned to delicious thyroid hormone stew. More fool me!
People with excess thyroid hormone usually get that way from either a) taking too high a dose of thyroxine medication (exogenous thyrotoxicosis), or b) something else. The former can be dealt with simply by reducing the dose. The latter is more complicated. Possible causes include:
Graves Disease - the most common cause of hyperthyroidism, Graves is an autoimmune disease which can be treated with anithyroid drugs, surgery to remove part or all of the thyroid, or a dose of radiactive iodine. After such treatment there's a substantial and ironic risk of hypothyroidism - i.e. not having enough thyroid hormone.
Tumours of the thyroid gland - thyroid adenoma is a benign tumour of the thyroid gland which may secrete large amounts of thyroid hormone, while thyroid nodules may be benign or malignant and again may or may not release thyroid hormone - in some cases they may actually inhibit its production, causing hypothyroidism.
Thyroiditis - inflammation of the thyroid gland. Although this often initially leads to high levels of thyroid hormone being released, it usually progresses to thyroid disfunction with the gland unable to produce sufficient hormones, and ultimately causes hypothyroidism. Around 7% of women experience temporary thyroiditis after giving birth (postpartum thyroiditis) which may lead to hyper- or hypothyroidism, or both; this usually resolves itself.
TSH hypersecretion - super rare, but usually caused by a pituitary adenoma (hurrah!). However, I believe there is also the possibility of a tumour in the hypothalamus causing excess Thyrotropin Releasing Hormone and hyperstimulating the pituitary gland to overproduce TSH, which in turn would hyperstimulate the thyroid gland to overproduce thyroid hormone. Again, it's very rare.
I guess really I should be grateful for this, as effectively I have two health conditions for the price of one. This blog is usually focussed mainly around the dramatic "there's a tumour in my head!" aspects of my pituitary adenoma, and poor little hyperthyroidism barely gets a look in, except for when I complain about my tachycardia/hair falling out/absurd appetite issues. But no longer! From now on I vow to go on about hyperthyroidism more. So you guys will get two lots of whingeing for the price of one!