thyroid.Every  time the availability of peripheral thyroid hormon is higher than the physiological need tissue to produce the framework of hyperthyroidism. To all of you happen to come across a patient who complains palpitations or diarrhea, which has strange reddening of the face, that shows his eyes out (exophthalmos), as if it were a tragic mask, and that, slim sight eye, which, having carried out investigations on the thyroid, his doctor found TSH "locked" and high values of thyroid hormones, FT3 and FT4. Now let's see, what it is and what it means TSH "locked". In addition, this patient may present with an anterior neck swelling, technically called "goiter," or, in most cases did not present any of this. (See also thyroid). Here we say, to make us understand that TSH is a pituitary hormone, a gland at the base of the brain that stimulates thyroid hormone production in FT3 and FT4. To use an analogy dear to us, we make an example of a jockey riding a horse whip lazy and must constantly because trot. Now, by analogy, the whip is the lazy horse and TSH, a thyroid that does not work properly (hypothyroidism). If, conversely, thyroid is like a "crazy horse" that runs incessantly, then the jockey would rather the need to pull the brake (eg. Methimazole care) instead of using the whip. So a thyroid "crazy", which secretes its own hormones (see below) has a TSH crashes, that tends to zero when you do the analysis, because the agency is involved with mechanisms of feed-back negative appuntola to stop production of that hormone stimulation.

The term thyrotoxicosis siindicano precisely the clinical, pathophysiological and biochemical, which has an excess of thyroid hormones that stimulate the body. These conditions depend on:

a) by the same factor which increases thyroid hormone production

b) the excessive production of thyroid stimulating hormone or TSH secretion by pituitary adenomas.

In particular we have the following thyrotoxicosis:

associated with thyroid hyperfunction

high production of TSH

factors tireostimolanti

Graves' disease

trophoblastic tumor

hyperfunctioning adenoma

toxic multinodular goiter

subacute thyroiditis

ectopic thyroid tissue

toxicosis 'hamburger'

Ovarian struma

The most common forms of hyperthyroidism are represented by Diffuse Toxic Goiter or Graves' disease, Basedow and Flajani (MDB) that is characterized by a diffuse goiter, signs of thyrotoxicosis and mucopolysaccharides and cellular infiltration with protrusion of the eyeballs and under ophthalmopathy and infiltrative dermopathy. The disease mainly affects women (7:1) and is associated with haplotypes HLA-B8, Drw3, BW 35 and BW 46. In families increased incidence appears to be due to a presumed autoimmune origin, and associated with other autoimmune diseases such as (whose genesis, ie, is dependent on movement of antibodies against the very structures of your body).

.. The etiopathogenetic mechanism that determines the increase in volume of the gland (toxic goiter) of MdB seems to be due to antibodies against the gland with stimulating, LATS or long-acting thyroid stimulator and it would of IgG produced by lymphocytes, ultimately there are other immunoglobulins, the TBII and TSH-binding inhibitory immunoglobulins and others that instead stimulate the thyroid cells in the production of cAMP, for which you would have a stimulating activity and immunoglobulins can be defined as "thyroid stimulating immunoglobulin" or IST. This could be due to immunosuppressive disorders of lymphocyte T suppressor. Even harder to understand is the formation dell'esoftalmo, which seems dependent on a union of IgG with the beta subunit of TSH with the formation of a substance EPS, or exophtamos Producing-substance.

Effects. The thyroid volume is increased in patients with infiltration of inflammatory cells, lymphocytes, macrophages and plasma cells; shows hyperplasia of the parenchyma with follicles are composed of cells that show increased high cytoplasmic vacuolation and papillary projections. The retrobulbar ophthalmopathy is characterized by accumulation of hydrophilic mucopolysaccharides and infiltration lympho-plasma cells.

Clinical picture. Appears diffuse goiter, a smooth surface, with palpation findings of thrill and auscultation of breath noise thyroid, there is excess circulating thyroid hormones, increasing, therefore, the metabolism, oxygen consumption and termogenenesi. The hands become hot and humid, there are redness at the base of the neck, due to vasomotor instability. The skin appendages show brittle hair that tends to fall, friaibili nails (onycholysis Plummer).
There is tachycardia (see arrhythmia), increased blood pressure, arrhythmia supraventricular, emotional instability and insomnia, fine tremors, muscle weakness and sometimes adynamia patients, creatinuria. The gastric system is involved with diarrhea (see link), discharges from 2-4 per day, hepatomegaly, increase in transaminases and alkaline phosphatase; presents the skeletal bone resorption of calcium that results in hypercalcemia and hypercalciuria with osteoporosis column. The hematopoietic system will have an increased hematocrit due to overproduction of erythropoietin. The endocrine system undergoes alterations consisting of increased conversion of cortisol into less active cortisone and ACTH secretion, which being known diabetogenic effect (diabetes) ACTH (hormone controinsulare), you will have hyperglycemia, the reproductive system changes going forward in the male impotence and loss of libido, menstrual irregularities in women. Compare exophthalmos due to infiltration by mucopolysaccharide material in the retrobulbar space, spastic upper eyelid retraction, expansion of rhyme (sign Dalrymple's) lack of convergence (sign Moebius), everything is realized in the clinical definition of "facies tragic" reminiscent of Greek tragedy and the masks used!

Care. It is proposed therefore to restore normal hormone levels (T3 and T4), where the TSH is often "locked" for negative feedback, that is reduced to a minimum. We therefore employ the compounds of the antithyroid activity of tioamidi (methimazole and propylthiouracil) at doses from 300 to 600 mg / day for the first and 20-60 mg / day for the second. The salt dosage until you reach the therapeutic effects (usually takes 6 months), then continues with a maintenance 50-200 mg / day for propylthiouracil, methimazole for 50-20. period of 12.18 months of treatment may lead to "remission" of thyrotoxic symptoms if treatment is sudden and carefully conducted. It takes, in addition, beta-blockers, drugs that reduce the frequency. Radiation therapy with 131I, gamma-emitting radioisotope is taken into account when necessary to determine a reduction of the parenchyma, through the action of harmful cells of radioisotope t. Surgical therapy aims to intervene where the doctor has failed and / or there are certain phenomena of compression on adjacent organs to t, eg. the recurrent laryngeal nerve (hoarseness), the trachea (wheezing, recurrent bronchitis, laryngitis etc...)

Toxic adenoma. We speak rather of toxic adenoma (TA) as part of t. is finding a neoplasm (benign tumor) capable of autonomous hormone secretion, detached from any adjustment to feedback. And 'a disease of women, the 3rd-4th week of life. The nodule thyroid scintigraphy appears like a globular mass of 2-3 cm, highly absorber (is colored with bright colors, yellow, red), while the rest of ghianola seems "off", that does not stain at all, and that is why TSH is blocked (the test is carried with the stimulation by TRH) stimulation and exercise on healthy part of t, is a painless lump, easily movable, either adherent to the skin or deep levels in solidarity with t.

Clinical picture. The events are thus overlapped with those of MdB, however, predominate signs related to the interest of the heart, with tachyarrhythmias, supraventricular arrhythmias and myocardial pain.

Treatment is surgical and healing is usually complete.

Gozzo plurinodulare. In this case, a goiter develops in patients with multiple nodules, the presence of pods, therefore, the gland that are hyperfunctioning and dropped from adjustments to feedback. The debut here, is slow and usually speaks of old fishing boats, where the scintigraphic examination t. ipercaptante is interposed with cold areas consist of cystic nodules (ATTENTION TO COLD NODULES! OFTEN HIDE INSIDE Neoplast!).

Clinical picture. As for M.d.B. and A. T. There is growth hormone and, therefore, tachycardia, heart failure, arrhythmias, asthenia, fatigue, hypermetabolism.

Therapy. Here also takes advantage of treatment with 131I and antithyroid drugs, thyroidectomy should be considered even if the surgical goiters are bulky and if some nodules were dysplastic or neoplastic.

Thyrotoxicosis in the thyroid.

Also deserve a nod as thyroiditis conditions that can be associated with hyperthyroidism. These inflammatory processes that affect the thyroid gland and, therefore, may cause the extraction of thyroid hormone during the inflammatory process, and are exchanged for ordinary sore throat. Can be distinguished:

forms of bacteria (pyogenic thyroiditis, thyroiditis, tuberculosis)

viral De Quervain,

Autoimmune (Hashimoto's thyroiditis and Riedel.)

Pituitary tumors.

It is usually independent of TSH-secreting macroadenomas, which does not respond to suppression by administration of thyroid hormones or to stimulation with TRH. So these players seem to suffer from Graves' disease, with high levels of free thyroxine, but no specific signs (exophthalmos, flushed skin, etc...) Also you can search for circulating the overproduction of alpha-glycoprotein subunit of TSH, with a ratio greater than 1:1.
 

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