Generalized Hypopituitarism

Hypopituitarism describes hormone deficiency states which have their cause in a partial or total loss of function of the anterior pituitary. Depending on the missing hormones very different clinical pictures show. are used for diagnosis, both the measurement of pituitary hormones (basal and after challenge) as well as imaging procedures. Treatment depends on the cause and is optionally in the removal of tumors and hormone replacement.

The hypopituitarism is divided into

Hypopituitarism describes hormone deficiency states which have their cause in a partial or total loss of function of the anterior pituitary. Depending on the missing hormones very different clinical pictures show. are used for diagnosis, both the measurement of pituitary hormones (basal and after challenge) as well as imaging procedures. Treatment depends on the cause and is optionally in the removal of tumors and hormone replacement. The hypopituitarism is divided into primary: caused by disorders affecting the pituitary gland Secondary: caused by disorders of the hypothalamus The various causes of primary and secondary Hypophyseninsuffizient are listed in the table below (see Table: Causes of hypopituitarism). Causes of hypopituitarism cause Examples causes primarily the pituitary concerning (primary hypopituitarism) tumors of the pituitary adenoma craniopharyngioma infarction or ischemic necrosis of the pituitary hemorrhagic infarction (stroke of the pituitary gland) shock, particularly post partum (Sheehan’s syndrome), or in diabetes mellitus or sickle cell anemia vascular thrombosis or aneurysm, in particular the internal carotid artery Inflammatory processes Meningitis (tubercular bacteria, fungi, malaria) abscesses pituitary sarcoidosis infiltrative disorder hemochromatosis Langerhans cell histiocytosis Idiopathic isolated or multiple pituitary deficiencies – Iatrogenic causes medication (eg. B. Hypophysitis due to anti-melanoma monoclonal antibody) radiation Surgical extirpation Autoimmune dysfunction of the pituitary gland Lymphatic Hypophysitis causes the hypothalamus primarily concerning (secondary hypopituitarism) Hypothalamic tumors craniopharyngioma ependymoma meningioma metastasis pinealoma Inflammatory processes sarcoidosis Neurohormomangelzustände the hypothalamus Isolated Multiple Iatrogenic surgical transection of the pituitary stalk trauma skull base fracture symptoms and complaints The symptoms depend on the underlying cause and the particular pituitary hormone to which it lacks and what’s missing. Occasionally, however, the onset is sudden and dramatic. The onset is usually insidious and is not noticed by the patient might. Most first growth hormone (GH), the gonadotropins and finally the thyroid stimulating hormone (TSH) and ACTH disappears. A vasopressin deficiency is rare in primary Hypophysenstörungen, but often in lesions of the pituitary and hypothalamus. The function of all target glands decreases when a generalized hormone deficiency exists (Panhypopituitarism). A luteinizing hormone (LH) and follicle stimulating hormone (FSH) results in children (to delayed puberty childhood hypopituitarism as a cause of short stature. Premenopausal women develop amenorrhea, decreased libido, regression of secondary sexual characteristics and infertility. Men exhibit erectile dysfunction, testicular atrophy, decreased libido, also a regression of secondary sexual characteristics and infertility due to impaired spermatogenesis. One GH deficiency can contribute to a feeling of weakness, but is usually asymptomatic and is often overlooked in adults. speculations about a possible role of GH deficiency could in the development of atherosclerosis has not been confirmed. the effects of GH deficiency in children will be discussed elsewhere. a lack of TSH has hypothyroidism result, and patients have a aufgeduns enes face, a gravelly voice, bradycardia and are sensitive to cold. An ACTH deficiency causes an adrenal atrophy with severe fatigue, hypotension as well as a stress intolerance and susceptibility to infections. An ACTH deficiency does not produce hyperpigmentation, as observed in a primary adrenal insufficiency. Hypothalamic defects can also affect the centers for appetite, which can lead to a syndrome that is similar to anorexia nervosa next to a hypopituitarism, or occasionally to hyperphagia with massive obesity. Sheehan’s syndrome. In women, it can occur after giving birth to a Hypophysennekrose by hypovolemia and shock directly related to the birth process. Lactation remains of postpartum and women complain of fatigue and loss of pubic and underarm hair. Pituitary describes a complex of symptoms caused by either hemorrhagic infarction a normal pituitary gland, or, more commonly, by a pituitary tumor. The acute symptoms consist of severe headache, stiff neck, fever, visual field defects and u. U. paralysis of the oculomotor nerve. Through the resulting edema can lead to a compression of the hypothalamus, come to hydrocephalus occlusus and subsequently somnolence and coma. It can be quite suddenly come to varying degrees of hypopituitarism and patients can develop a collapse of the vascular regulation due to lack of ACTH and cortisol. The cerebrospinal fluid is often hemorrhagic and the MRI shows bleeding. Diagnosis MRI or CT Free thyroxine (T4), TSH, prolactin, LH, FSH and levels of testosterone (in men) or estradiol (in women) cortisol plus provocation tests of the pituitary-adrenal axis Occasionally another provocation tests The clinical signs are often non-specific, and the diagnosis must be made with great certainty before subjecting a patient a lifelong hormone replacement. A pituitary disorder must of anorexia nervosa, chronic liver disease, myotonia dystrophic, a polyglandular autoimmune disease (see table: definition of a generalized Panhypopituitarism other selected diseases) and disorders of other endocrine glands are distinguished. The clinical picture can be especially confusing if simultaneously the functions of several glands are limited. With imaging and laboratory tests for signs of hormonal deficiencies and structural pituitary changes should be sought. Delimitation of a generalized Panhypopituitarism other selected diseases disease differentiators anorexia nervosa More frequent occurrence in women, cachexia, pathological ideas regarding diet and body image; Receipt of the secondary sexual characteristics despite amenorrhea; increased levels of GH and cortisol Alcoholic liver disease or hemochromatosis * evidence of liver disease, laboratory values ??myotonia dystrophica Progressive weakness, premature baldness, cataract; Signs of premature aging in the face; Laboratory values ??Polyglandular autoimmune disease † levels of pituitary hormones * Can cause hypogonadism and generalized debilitation. † If the affected glands are target glands of the pituitary gland. Imaging techniques, patients should be studied by high-resolution CT or MRI better, if necessary also with contrast medium (pituitary to exclude structural changes such. As adenomas). PET is used in only a few highly specialized centers for scientific purposes and is therefore little used. If no modern neuroradiological procedures are available, it is possible to detect pituitary macroadenoma with a diameter> 10 mm with a simple lateral radiograph of the sella. Cerebral angiography is indicated only if other imaging methods evidence periselläre vascular pathology or an aneurysm zeigen.Technische investigations The initial evaluation should include an examination for a TSH and ACTH deficiency, since both can be potentially life threatening. The investigation on deficiencies of other hormones will be discussed below. Free T4 and TSH levels should be determined. The levels of both hormones are usually low in generalized hypopituitarism, however, sometimes a normal TSH shows with reduced free T4. In contrast, have elevated TSH levels with reduced free T4 indicates a primary disorder of the thyroid gland. 200-500 micrograms synthetic thyrotropin releasing hormone (TRH) given over 15 to 30 s can help distinguish patients with hypothalamic disorders of patients with pituitary defects. Nonetheless, the test is not often used. Serum TSH levels are 0, 20 and 60 min after injection was measured. With intact pituitary function TSH should having a peak after 30 min to> 5 mU / l increase. A delayed increase in serum TSH levels can be seen in patients with hypothalamic disorder. Occasionally, patients with primary pituitary disorder a delayed rise. Cortisol levels in the serum are not reliable indicators of ACTH-adrenal axis function alone, although a very low Serumkortisolspiegel (<3.5 g / dl at 7:30 to 9:00) almost certain points in the morning on a Kortisoldefizit. One of the various challenge tests should be performed. The short ACTH stimulation test is a safer and less labor-intensive test for adrenocortical insufficiency than the insulin tolerance test. When short ACTH stimulation test 250 ug synthetic ACTH are injected i.v. or i.m. (Standard Test dosage) or 1 ug i.v. added (test low dose), and 30 and 60 min later, the levels of cortisol is measured in the blood. The cortisol should increase significantly; a peak value of <20 ug / dl is abnormal. But only if the test is carried out at least 2-4 weeks after the start of the lack of short ACTH stimulation test shows in secondary adrenocortical insufficiency flashy values. Before that time, the adrenal glands are not atrophied and remain responsive to exogenous ACTH. The insulin tolerance test is the most accurate method for the determination of ACTH (as of GH and prolactin), because of its requirements but it is likely to remain reserved for those patients in whom the short ACTH stimulation (if confirmation is required) has failed or when a test must be carried out within 2-4 weeks after a possible violation of the pituitary gland. I.v. acting insulin at a dose of 0.1 I.U./kg body weight is applied over 15-30 s. Venous blood for the determination of levels of GH, Cortisol and glucose is taken before the administration of insulin and in each case 20, 30, 45, 60 and 90 minutes thereafter. When the glucose levels below 40 mg / dl ( rise 7 g / dL or> 20 g / dl. (Caution: This test can be harmful in patients with severe Panhypopituitarism, diabetes mellitus or in elderly patients It is contraindicated in patients with coronary heart disease or epilepsy During testing, medical personnel should be present…) As a rule occur only temporary sweating, tachycardia and nervousness. If the patient complains of palpitations, is unconscious or has a seizure, the test should immediately i.v. Administration of 50 ml of 50% glucose solution to be terminated. Neither the short ACTH stimulation test nor the insulin tolerance test are capable of distinguishing between a primary (Addison’s disease) and secondary (pituitary) adrenal insufficiency. Tests that allow this distinction can be made and the evaluation of the axis hypothalamus-pituitary-adrenal gland are described with Addison’s disease. Test carried out to distinguish between primary, secondary (pituitary) and tertiary (hypothalamic) causes the adrenal insufficiency – The corticotropin-releasing hormone (CRH). CRH at a dose of 1 ug / kg i.v. is rapidly applied. Serum levels of ACTH and cortisol are 15 min before the test and then 0, 15, 30, 60, 90 and 120 min after injection determined. Side effects are temporary flushing, a metallic taste in the mouth and a mild, transient hypotension. Prolactin levels are routinely determined as basal. These levels are often elevated in the presence of a large pituitary tumor by five times, even if the tumor itself does not produce prolactin. The tumor compresses the pituitary stalk and prevents dopamine, which inhibits the production and secretion of prolactin in the pituitary gland, reaching the pituitary gland. Patients with such Entzügelungshyperprolaktinämie often have a Hypogonadotropismus and secondary hypogonadism. The measurement of basal levels of LH and FSH in the evaluation of a hypopituitarism in postmenopausal women who are not taking estrogen preparations and for which the values ??of circulating gonadotropin normally high (> 30 mI.E./ml), very helpful. Although the Gonadotropinwerte in other patients are rather low with Panhypopituitarism, there is an area of ??overlap with normal values. In response to the application of synthetic gonadotropin releasing hormone (GnRH) in a dosage of 100 ug i.v. both the values ??of LH should (with a peak 30 min after administration) and the values ??of FSH (with a peak 40 min after administration of GnRH) to increase. In the case of hypothalamic-pituitary dysfunction normal, reduced or absent responses to GnRH can be observed. The normal increase of LH and FSH to GnRH is subject to very strong variations. The application of exogenous GnRH does not help to distinguish hypothalamic between primary and primary pituitary disorders. Screening for GH deficiency in adults is not recommended unless a treatment with GH is envisaged (eg. As in patients with otherwise vollsubstituiertem hypopituitarism and lack of drive at a reduced quality of life, in which other hormones were completely substituted). A GH deficiency is suspected when a lack of ? 2 other pituitary hormones is. However, normal levels do not rule out a GH deficiency. Since GH levels are to be determined depending on the time of day and other factors and heavy, the levels of insulin-like growth factor 1, (IGF-1), which correlate with GH used. A provocation test for GH secretion may be necessary (growth hormone deficiency in children: diagnosis). Although the benefits of provocative tests of pituitary using releasing hormones must be determined not only there, if once the decision is made for such a test, the most efficient way to evaluate several hormones at the same time. GH-releasing hormone (1 ug / kg), CRH (1 ug / kg), TRH (200 ug) and GnRH (100 ug) are combined in a period of 15-30 s i.v. applied. Glucose, cortisol, GH, TSH, prolactin, LH, FSH and ACTH are over the next 180 min at short intervals determined. The normal hormonal response is the same as already described for the individual testing. Therapy HRT Causal treatment (eg., Tumor) Treatment consists of the substitution of the hormones of the insufficient target glands, as already discussed in the relevant chapters of this section and elsewhere in the MSD Manual. Adults ? 50 years which have a GH deficiency, occasionally with growth hormone in a dose of from 0.002 to 0.012 mg / kg s.c. once daily. The benefits of treatment are increased drive and quality of life, increased muscle mass and decreased body fat. Assumptions that the substitution can prevent progression of atherosclerosis with growth hormone, are not yet occupied. In the pituitary apoplexy immediate surgical intervention is justified if suddenly visual field or oculomotor palsy occur or if a clouding of consciousness due to compression of the hypothalamus and the third ventricle goes into a coma. Although in some cases, treatment with high-dose corticosteroids in combination with general measures may be sufficient for an immediate transsphenoidal decompression should be performed both surgical procedures and radiation therapy may have a loss of function of other pituitary hormones results in general. In irradiated patients, the loss of endocrine function can develop slowly over several years. Therefore, the hormone status should often be best controlled at 3 and 6 months and then annually for at least 10 years and preferably up to 15 years after radiation therapy. Such controls should include at least the function of the thyroid and adrenal glands. Because of fibrosis in the optic chiasm, it can also cause vision problems. Imaging of the sella and a review of the field should be performed at least every 2 years for a total of 10 years at first, especially if the tumor was not completely removed.

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