Saturday, May 27, 2017

Hypopituitarism caused by Ectopic pituitary stalk


Something I learned last week is that my growth, hormone and corticosteroid deficiencies were caused by the absence of a pituitary stalk and that pituitary fossa is 3mm instead of the 5mm average.

Pituitary Stalk (Infundibulum): This critical but delicate neurovascular structure (comprised of nerves and blood vessels) is the connection between the hypothalamus and the pituitary gland. It carries the hypothalamic releasing hormones for the anterior pituitary gland and also axons from the magnocellular neuro-secretory cells of the hypothalamus to the posterior pituitary where they release their hormones oxytocin and antidiuretic hormone (ADH) into the blood. 


The Pituitary Gland
The pituitary gland is at the anatomical and functional crossroads of the brain, mind and body. Weighing less than one gram and measuring a centimeter in width, the pituitary is often called the "master gland" since it controls the secretion of the body’s hormones. These substances when released by the pituitary into the blood stream have a dramatic and broad range of effects on growth and development, sexuality and reproductive function, metabolism, the response to stress and overall quality of life.

This small, bean-shaped gland is located below the brain in the skull base, in an area called the sella turcica. The gland is regulated by a brain region called the hypothalamus which is connected to the pituitary gland by a thin delicate vascular connection called the pituitary stalk or infundibulum. The pituitary is divided into a larger anterior region (adenohypophysis) and smaller posterior region (neurohypophysis). Directly above the pituitary are the optic nerves and the optic chiasm as they project to the eyes. On each side of the pituitary is the cavernous sinus which is a venous channel through which runs the carotid arteries that carry blood to the brain, and important nerves that control eye movements and facial sensation. Because of the proximity of the pituitary to these major intracranial nerves and blood vessels, and the vital hormonal control the pituitary provides, disorders of the pituitary can cause a wide spectrum of symptoms, both hormonal and neurological.



Listed below are the specific hormones produced by the pituitary:

Growth Hormone (GH): This is the principal hormone that, among many other functions, regulates body and brain development, bone maturation, metabolism and is essential for healthy muscles.

Luteinizing Hormone (LH) and Follicle Stimulating Hormone (FSH): These hormones control the production of sex hormones (estrogen and testosterone) as well as sperm and egg maturation and release.

Prolactin (PRL): This hormone stimulates secretion of breast milk.

Thyroid Stimulating Hormone (TSH):  This hormone stimulates the thyroid gland to release thyroid hormones. Thyroid hormones control basal metabolic rate and play an important role in growth and maturation. Thyroid hormones affect almost every organ in the body.

Adrenocorticotropic Hormone (ACTH): This hormone triggers the adrenal glands (located above the kidneys) to release the hormone cortisol which in turn, regulates carbohydrate, fat, and protein metabolism and is essential in the stress response.

Vasopressin - Also called anti-diuretic hormone (ADH): This hormone promotes water to be reabsorbed by the kidneys and is thus essential in water and electrolyte balance.


In disease states, the pituitary may under- or over-produce hormones. Decreased pituitary hormone production is called hypopituitarism or pituitary failure. The symptoms and treatments for pituitary failure are listed below:


Hormone Deficient  Symptoms  Treatment GH Children: Growth delay
Adults: Decreased muscle mass, increased body fat, elevated cholesterol, low bone density (osteoporosis), impaired psychological well-being,
poor quality of life Recombinant Human Growth Hormone- Given once daily as an injection under the skin

LH/FSH Decreased libido, erectile dysfunction, irregular or absent menses, decreased body hair, decreased muscle strength, hot flashes, mood changes Men: Testosterone- Given as either topical gel or patch or injections

Women: Estrogen + Progesterone-Given as either topical patch or pills  

ACTH Poor appetite, nausea, weakness, vomiting, low blood sugar, low blood pressure, dizziness, body aches Hydrocortisone or Prednisone-Given as daily pills  

TSH Fatigue, weakness, cold intolerance, dry skin, constipation, heavy/painful menses, weight gain, memory loss, mood disturbance Levothyroxine – Given as daily pills (some examples include Synthroid or Levoxyl or Levothroid or Armour Thyroid)  

Prolactin Inability to lactate No treatment available  

Vasopressin (ADH) Increased thirst and frequent urination DDAVP- Given either as daily pills or nasal spray


Infundubulum - pituitary stalkInfundubulum - pituitary stalk

Meaning of ectopic

A gland in the wrong place is referred to as ectopic, and an ectopic gland at the base or back of the tongue is a lingual thyroid.


Pituitary glandPituitary gland
Ectopic pituitary is a rare congenital anomaly of the pituitary gland. The patient usually presents with panhypopituitarism and has a small or absent infundibular stalk on advanced imaging. Usually MRI is the examination of choice which should demonstrate the displaced neurohypophysis which can be isointense to brain parenchyma but will demonstrate strong contrast enhancement with contrast administration. Associated findings also include absence of tissue within the pituitary sella. Although other lesions can present with a suprasellar "hot" spot (enhancing lesion), coupled with the absence of tissue in the sella and the clinical history the diagnosis is essentially confirmed. The anterior pituitary - adenohypophysis - is hypoplastic or absent.

Cushings Disease

I present all of the symptoms of Cushings Disease except that I don't have a tumour, my pituitary was just underdeveloped and there is an empty space similar to that of a tumour that has been removed.  I have the hump or padding on the back of my neck and all the health implications that come with Cushings.

Symptoms include rapid weight gain, particularly of the trunk and face with sparing of the limbs (central obesity). A common sign is the growth of fat pads along the collar bone and on the back of the neck (buffalo hump) and a round face often referred to as a "moon face." Other symptoms include hyperhidrosis (excess sweating), telangiectasia (dilation of capillaries), thinning of the skin (which causes easy bruising and dryness, particularly the hands) and other mucous membranes, purple or red striae (the weight gain in Cushing's syndrome stretches the skin, which is thin and weakened, causing it to hemorrhage) on the trunk, buttocks, arms, legs or breasts, proximal muscle weakness (hips, shoulders), and hirsutism (facial male-pattern hair growth), baldness and/or cause hair to become extremely dry and brittle. In rare cases, Cushing's can cause hypercalcemia, which can lead to skin necrosis. The excess cortisol may also affect other endocrine systems and cause, for example, insomnia, inhibited aromatase, reduced libido, impotence, amenorrhoea/oligomenorrhea and infertility due to elevations in androgens. Patients frequently suffer various psychological disturbances, ranging from euphoria to psychosis. Depression and anxiety are also common.[6]

Mnemonic

C - Central obesity, Cervical fat pads, Collagen fibre weakness, Comedones (acne)
U - Urinary free cortisol and glucose increase
S - Striae, Suppressed immunity
H - Hypercortisolism, Hypertension, Hyperglycemia, Hypercholesterolemia, Hirsutism
I - Iatrogenic (Increased administration of corticosteroids)
N - Noniatrogenic (Neoplasms)
G - Glucose intolerance, Growth retardation


MRIMRI
   

production of cortisolproduction of cortisol