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Endocrine System

Group of glands that are integrated/interrelated, release hormones & affect every cellin the body. Many diseases are related to too much/too little of 1 or more hormones.

A Few Key Terms . . .

• Endocrine system: Series of ductless glands that secrete hormones directly into blood

• Negative feedback: decrease in function in response to a stimulus

• Master gland: The pituitary gland, its secretions controls other endocrine gland function

Negative feedback

• Occurs naturally in the body

• “Control mechanism” used to regulate secretion of hormones

• Hormones released when levels are low or there is a need to increase levels; then it “shuts it off”

An example: an event (such as an infection) causes hypothalamus to stimulate pituitary to release ACTH; ACTH causes adrenal cortex to release cortisol, which inhibits inflammation.

When cortisol reaches a certain blood level, hypothalamus tells pituitary to stop releasing ACTH, adrenal gland stops production (this is negative feedback mechanism)

Basics of Endocrine System:Anatomy Review

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Endocrine Glands

•Pituitary•Thyroid•Adrenal•Pancreas•Sex (ovary, testes)•Pineal gland?*

*function unclear, may produce melatonin

Pituitary gland- Remember from A& P?

“Master gland” Produces hormones that control

other glands Works in conjunction with

hypothalamus (attached to it) Part of CNS Controls growth, maturity,

sexuality, & metabolism Anterior lobe most productive-

secretes many hormones such as ACTH (adrenocorticotropic hormone), prolactin, TSH, Growth hormones,… and others

Hyperpituitarism

Prolonged – excess hormone production by the anterior pituitary gland, most common cause-pituitary tumor

Mandible grows resulting in skeletal class 3

Hands, feet, internal organs, tongue, forehead large

Diabetes, cardiovascular complications, goiter, muscle/joint pain, fatigue

Treatment involves removing the pituitary gland

What is the difference between Gigantism & Acromegaly?

Adrenal Glands

Located on each kidney

Have two parts, cortex and medulla (each release different hormones)

They control growth, inflammation, blood pressure, electrolyte balance & sexuality

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Adrenal cortex releases Glucocorticoids Cortisol (naturally occuring “steriod”)

Normal adult produces 20 mg of cortisol every day.This production increases in times of stress ….(Cortisol helps the body respond to stress- antiinflammatory)

When body under constant stress, body does not havea chance to return to normal state. Results include:High BP, blood sugar imbalances, lowered immunity, increase in abdominal fat deposits, autoimmune diseases, etc….A result of a “fast-paced society” ?

Bodybuilders may take anabolic steroids to build muscle

Side effects are many-- including irritability & extreme aggressive behavior, impotence, skin changes (such as acne), feminization or masculinization, increased cardio problems, kidney/liver problems, swelling “puffiness” of the tissues

Glucocorticoids can also be given by Rx for illnesses (Prednisone/hydrocortisone)

Addition of Synthetic Steroids: Dangerous! Negative feedback complication

-Rule of Twos

If a patient takes 20 mg or more of hydrocortisone a day for two weeks, pituitary may not produce adequate ACTH for two years!This causes a disruption in the naturally occurring negative feedback mechanism.

Impaired wound healing & masking of infectionMay precipitate adrenal crisis if patient stressed

(weakness, syncope, cardiovascular collapse, shock, or death)

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Cushing’s Syndrome

o Caused by excessive cortisol

o Moon face, humpback (fat on back)

o Symptoms include: severe fatigue, high BP, high blood sugar, excess hair growth

o Can also be result of a tumor- either pituitary gland or adrenal gland (then Cushing’s Disease) or taking Rx cortisol for extended periods of time (i.e. for Rheumatoid Arthritis, Lupus, Diabetes, Hyperthyroidism, Crohns, etc…)

o Diagnosis by a 24-hour urine test

Adrenal Insufficiency: Primary/Secondary

too little cortisol or ACTH Causes severe fatigue, muscle weakness,

low blood pressure- can be life threatening (from adrenal crisis)

May be result of tumor, surgery, steroid use or autoimmune disease (destroys the adrenal glands)

Can cause gradual abnormal pigmentation of skin (bronzing of skin), mucosa, & lips (if Addison’s Disease)

Addison’s Autoimmune Disease- Rare-occurs 1:100,000

Treat with Desoxycorticosterone; Fludrocortisone

Get “bronzing” of skin & mucosa

Addison’s Disease

Adrenal Drugs used in Dentistry

• Epinephrine used as vasoconstrictor & controls bleeding (hemostasis)

• Kenalog in Orabase for intraoral infections (hydrocortisone)

• Prednisone (Medrol dosepak) for inflammation

• Check BP!

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Parathyroid Gland

Sole purpose is to regulate calcium & phosphorus metabolism in the body; effects bone density

Hyperparathyroidism

Excess secretion of parathyroid hormone (PTH)

Elevated blood levels of calcium & low phosphorus levels

Abnormal bone metabolism

Most common cause- benign tumor (but can also be caused by renal disease)

More common in woman-usually > 60 years

Joint pain/lethargy *Teeth become loose *Changes in mandible/maxilla

(radiolucencies/mottled appearance on x-ray)

Thyroid gland

o Produces Thyroid Hormones -controlled by the hypothalamus and the pituitary gland <TSH>

o T4 & T3

o Controls metabolism- and effects almost every cell and organ in the body

o Normal function requires iodine, which helps produce thyroid hormones

o In US, iodine deficiency rare – put in SALT (“iodized”)

Butterfly shape- sits in baseof neck under Adam’s apple; in frontof trachea

Thyroid gland effects:

• Energy

• Muscle function

• Heart/lungs

• Brain chemistry

• Stomach/intestines

• Skin, hair, nails

• Sexual function/cycle/fertility

• Bones

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How can you detect a goiter?

NORMAL

*use caution- why?

Thyroid should bedifficult to detect (due to size)move gently side- to- side Watch patient swallowAsk about difficult swallowing (“lump in throat”), breathing, hoarseness, coughing, etc…

Subacute Thyroiditis

• Temporary inflammation of thyroid gland

• Usually tender

• Treat with Ibuprofen

• Symptoms of hyperthyroidism

Hypothyroidism- too little

• Fatigue /severe lack of energy • Weight gain • Feeling cold • Dry, peeling skin and hair loss • Slow digestion/poor nutrition (anemia common)• Loss of coordination/balance• Slowed thinking “brain fog”• Pain in joints/aching • High levels of inflammation• Goiter • Generalized edema• High chol/LDL- susceptible to cardio disease

Hypothyroidism- diagnosis & cause?

o Signs/symptoms are confusing and fairly nonspecifico Often mistake for menopause, normal aging, and stresso Can be caused by iodine deficiency (rare in US), previous treatment for hyperthyroidism, or more commonly autoimmune disease (Hashimoto’s thyroiditis) where the thyroid can go through bouts of hyper-hypo symptoms and gradually quit working all together due to permanent destruction of glando More common in woman- middle age typically time of diagnosiso Known as cretinism in childreno Severe consequences if left untreated (myxedema & birth defects during pregnancy)o Much more common than hyperthyroidism & thyroid cancer

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Treatment for Hypo

• Taking thyroid hormones every day

• Getting the right amount (this can be tricky)

• Testing hormone levels on a regular basis

Hyperthyroidism(Thyrotoxicosis)

Most common symptoms

Tremors, increased nervousness, anxiety, panic Irritability/agitation/impatience/outbursts Rapid heart beat or palpitations (often 100+) Weight changes Fatigue; physical exhaustion; muscle weakness Changes in menstrual cycle & digestion Sore throat, goiter, difficulty swallowing, fullness/warmth/tingling in the

throat, choking on food Brain “fog” - can’t concentrate/think straight Insomnia Hot flashes, night sweats, sweaty palms (heat intolerance) Loss of hair, including eye brow

Hyperthyroidism

Nutritional deficiencies, especially anemia (EOIO exam?)

Poor stress tolerance; poor reaction to stress (emotional instability)

Increased appetite

Impulsive- hyperactivity- can’t sit still

Changes in eyes (staring, irritation, swelling, light sensitivity)

Osteoporosis (long term result)

Fertility issues- miscarriage not uncommon

Other common symptoms/side effects:

Hyperthyroidism

• Usually caused by Graves Disease (80-90%)- autoimmune disease

• Can also be caused by benign or malignant nodules

• Some degree of Thyroid Eye Disease (TED) usually accompanies Graves

• Severe consequences if left untreated- especially to the heart

Exopthalmus

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How do they check the Thyroid?

• Goiter (visual)• “Bruit”• Thyroid panel

Treatment Hyperthyroidism

Radioactive Iodine Treatment (RAI) – ablation of thyroid gland Surgery- partial or complete removal of thyroid (thyroidectomy) Antithyroid medication- (ATD’s) – Methimazole

(Tapazole or Carbimazole) or Propylthiouracil (PTU) Other meds may include- Propranolol or Atenolol

(beta blockers), Prednisone, antidepressants & anti-anxiety, & insomnia medications

In Dentistry….The Hyperthyroid patient

• Epinephrine typically contraindicated with hyperthyroid patients• May require higher than usual doses of CNS depressants• Pain tolerance usually much lower (increase in anxiety)• Be careful of aggressive palpation of the thyroid • Lymph nodes usually chronically swollen/tender (autoimmune disease)• Increased heart rate unless on beta blocker• Often see accelerated tooth eruption, loss of alveolar bone, & rapidly

progressive periodontal disease• “Stability” or euthyroid in hyperthyroidism difficult on medication

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What is “Thyroid Storm?”

Recognizing who is at Risk for Thyroid Disorders

o Women are affected by thyroid problems much more frequently than men (1:4-5 chance of developing thyroid issues)

o Thyroid problems often arise after age 30o About half of all the people with thyroid disorders are undiagnosedo Pay special attention to children, women who have recently delivered

a child or gone through a “crisis” period & elderly

** The thyroid is very sensitive to radiation (Hiroshima, Chernobyl & nuclear testing), STRESS, immune system responses, poor diet, environmental exposures, and other hormonal changes, possibly from ESTROGEN. Also Fluoride?!? (debate ongoing); The thyroid gland can often simply “wear out” (similar to the pancreas); Potassium iodide in high doses is given as a “blocking agent” in case of nuclear emergency

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Autoimmune diseases are common, affecting more than 23.5 million Americans …

Autoimmune Diseases

Known also as immunodeficiency; parts of the self are seen as “antigens” or foreign and therefore the body inadvertently attacks

Most studies indicate that 10 % of the world’s population test positive for autoantibodies

Autoimmune diseases tend to run in families

Typical patient 30-50 years old and a woman

Many autoimmune diseases will co-exist (have one, more prone to more…..)

Examples of autoimmune diseases– Celiac, Addison’s, Graves, Rheumatoid arthritis, Diabetes I, Sjogren, Hashimoto’s, Lupus, Pernicious anemia, Pemphigus vulgaris, Pemphigoid, Crohn’s, Myasthenia gravis, MS, Psoriasis, Scleroderma, . . .etc… .

Many autoimmune diseases have oral manefestations!

What does you family history show??

There are approximately *56,000 new cases of thyroid cancer each year in the United States. Females are more likely to have thyroid cancer at a ratio of 3-4:1. Most common after age 30 and its aggressiveness increases significantly in older patients. *5th most common cancer in woman

*according to cancer.net

Thyroid CancerThe majority of patients present with a nodule or goiter which typically does not cause symptoms

Occasionally, symptoms such as hoarseness, neck pain, difficulty swallowing, and enlarged lymph nodes do occur

Types of thyroid cancer- papillary (most common), follicular, medullary, & anaplastic

Treatment includes total thyroidectomy and sometimes RAI

5 year survival rate approx 97% (if hasn’t spread)

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Although as much as 50 % of the population will have thyroid nodules (very few are palpable) the vast majority are benign (usually 90%).

Young people usually do not have thyroid nodules However, with age, more develop.

By the time we are 80, 90% of us will have at least one nodule!

Female Hormones

Drugs used in Menopause – HRT (pills, patch, creams, Bioidentical, etc…)

Some replace only estrogen, progestin, & others multiple hormones, including testosterone

Hormones naturally secreted primarily by the ovaries- vary daily

Present in oral contraceptives Effects oral tissues Can have serious side effects

Oral Contraceptives

Contain combinations of progesterone and estrogen

Prevents ovulation

Require stomach bacteria to be absorbed into bloodstream

Patients on antibiotics may have less bacteria, therefore contraceptives may be ineffective

99 % effective if patient compliant

Typically taken for 21 days

Newer types available (extended cycle)

Oral side effects

Other types? Injectables… etc

Male Hormones

Myth or reality? Drugs used in Andropause or “Male Menopause” – HRT

(pills, patch, creams, Bioidentical, etc…) Androgens Hormones can also be used as

treatment for cancer