hypopituitarism

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I- Introduction / Definition :

  • The IAH or anterior hypopituitarism is defined as the & rsquo; insufficient production of hormones from the adenohypophysis or anterior pituitary.
  • His signs are linked d & rsquo; a part in the failure of pituitary gonadotropins (TSH, ACTH, LH and FSH, GH, PRL) and d & rsquo; secondly deficit of the production of each of the endocrine glands submitted to pituitary stimulation (thyroid, corticosurrénale, gonads……….).

II- REMINDERS :

A- anatomy :

  • The pituitary and the hypothalamus are small hazelnut-shaped gland located at the base of the brain.
  • The Pituitary measure 5 mm high 15 mm wide and 10 mm. It weighs 60g, it is contained in a bony box called the sella saddle dug into the sphenoid bone.
  • The drift hypothalamus primitive diencephalic vesicle. It is located in the middle part of the skull base, behind the optic chiasm, and forms the floor of the 3rd ventricle.
  • between these 2 glands found nerve fibers and blood vessels that constitute the pituitary stalk and allows communication between these 2 organs.
  • Vascularization is ensured by the pituitary arterial system and the hypothalamic pituitary portal system.

B- Physiology :

  • L & rsquo; hypothalamus is a hub of interrelations between the nervous system (I sensorialité, emotional life, memory…) and the endocrine system
  • The pituitary gland has two parts :

* the adénohvpophvse : glandular part of the pituitary gland that secretes hormones six: GH, TSH, FSH, LH, PRL, ACTH whose actions on target tissues are summarized below (Table 1).
* and neurohvnophvse or rear portion which contains two hormones ADH (or vasopressin) and oxytocin (OT)

  • Each hormone produced in response to a stimulus acts on the pituitary hypothalamic-pituitary system to regulate its own level of secretion (the feedback or Feed back).
Board 1 : main effects of pituitary hormones

III- CLINIOUE :

A- Type Description : overall hypopituitarism of & rsquo; adult :

  • pale facies, alabaster hue, with a very expressive and youthful face.
  • thin skin, atrophic, dried.
  • hypopilosité face, axilla and sexual regions.
  • Thin hair, brittle, areolas breasts depigmented.
  • subject adynamic, asthenic,indifferent, chilly.
  • in humans : voice change : low, female atonality.

B- own signs to deficits of each pituitary axis: see tableau.2

C- clinical forms :

* At the & rsquo; child = irtfantilo-dwarfism :

  • harmonious stature, acromicrie, abdominal adiposité, mi crop enis, impuberism

* In the elderly : Table depressed or insane pace,falls repeatedly.

IV- EXPLORATIONS OF IAH :

  • The hypothalamic-pituitary MRI is the key examination for the etiologic diagnosis of hypothalamic-pituitary region.
  • Fundus and visual field: looking for a decrease in visual acuity, a compression of the optical channels : hémianopsie bitemporale, quadrantanopia higher oral Temp sometimes scotoma.
  • Hormonal exploration according to each pituitary deficiency are summarized in Table 2.
Tableau.2 : arguments : clinics, biological and hormonal each hypopituitarism

V- THE etiologies of IAH :

WE- TREATMENT :

The etiological treatment if possible :

  • resection of a tumor.
  • of corticosteroids hypophysites.

Replacement therapy in LIFE :

– Treatment of adrenocorticotropic deficiency :

  • Education +++
  • Hydrocortisone: 20 30mg per day, dose increase under stress, d’infection, trauma
  • normosalée Food.

– Treatment of thyroid stimulating deficit :

  • LEVOTHYROX dose escalation to reach the average dose of 100 microg/j.
  • Monitoring of treatment by measuring the plasma T4.

– Treatment of gonadotropin deficiency :

  • Man ;.IM injection every 3 Testosterone weeks late (ANDROTARDYL):250mg.

*Women : estrogen plus progestin to produce an artificial cycle.

– Treatment of growth hormone deficiency :

At the & rsquo; child +++ to correct stunting by the synthetic GH.

VII- CONCLUSION :

  • It is important not to miss a possible pituitary insufficiency based on clinical history and clinical.
  • So it must actively search for suspected.
  • The adrenal hormone therapy is the most vital.
  • Be sensitive to small signs
  • vital treatment for adrenocorticotropic deficiency and thyroid stimulating
  • Supplementation with sex hormones is needed for sexuality and bone mineralization.
  • GH supplementation is proposed.

Course Dr S. BENSALEM – Faculty of Constantine