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ADRENAL AND THYROID DISORDERS
Claire Nowlan MDJan 9, 2004
The Adrenal Glands Medulla - part of the sympathetic
nervous system produces epinephrine and norepinephrine
Cortex produces: 1) Aldosterone (a mineralcorticoid)– acts
mainly on the cells of the kidney tubules Regulation of plasma salts – Na and K Blood pressure Blood volume
2) Androgen and Estrogen
The Adrenal Cortex 3) Cortisol (a glucocorticoid)
Catabolizes proteins and converts the resultant amino acids to glucose
Inhibits inflammation Maintains homeostasis Secreted secondary to stress (cold, fasting,
starvation, hypotension, hemorrhage, surgery, infections, pain, severe exercise, emotional trauma)
Diurnal variation – highest in the AM Essential for life
Regulation of Secretion
s tress
A d ren a l C ortexC ortiso l
A n te rio r p itu ita ryA C TH
H yp oth a lm u sC R H
cortico trop in -re leas in g h orm on e
Synthetic glucocorticoids Most common ones are prednisone,
methylprednisone, dexamethasone. Used to decrease inflammation in :
Rheumatoid arthritis, SLE, asthma, inflammatory bowel disease, organ transplantation
Long term side effects include Hypertension, osteoporosis, diabetes,
glaucoma, delayed wound healing, peptic ulcers
Hyperadrenalism Cushing’s syndrome Commonly caused by
adrenal/pituitary neoplasm or iatrogenic
Symptoms: weight gain, weakness, easy bruisibility, depression, insomnia, impotence
Clinical symptoms: acne “moon facies”, abdominal stria
Hypoadrenalism Primary
(problems with adrenal gland)
“Addison’s disease”
Etiology includes autoimmune, Tb or HIV infections, metastatic
Secondary Etiology includes
excess steroid administration or pituitary/ hypothalmus problems
Hypoadrenalism Acute adrenal insufficiency is a medical crisis Chronic disease usually presents with vague
complaints Postural dizziness Weakness Nausea Anorexia Weight loss
Classic findings – hypotension, hyperpigmentation
If you identify a patient with adrenal insuffiency Bravo! Refer to physician, and defer dental treatment until stable
Lab tests Difficult to do 24 hour urine cortisol ACTH suppression test
Medical management Hyperadrenalism
Surgery/radiotherapy to destroy pituitary/adrenal tumour
Ketoconazole inhibits adrenal hormone biosynthesis
Hypoadrenalism Supplement mineralcorticoids,
glucocorticoids Avoid ketoconazole, P450 inducers
(rifampin, phenytoin, barbituates In surgery tx same as patient on steroids
Dental managementPatients on steroids hyperadrenalism
Select a non NSAID analgesic - re risk of peptic ulcers
Osteoporosis is related to periodontal bone loss
Monitor BP You don’t want to provoke an
adrenal crisis
Oral Steroids and procedures Determine length of time steroid
taken Determine dose of steroid For routine/minimally invasive
procedures Ensure patient has taken regular
steroid dose – preferably within 2 hours of procedure
For major procedures Using general anesthesia, 1+ hours,
significant blood loss, in sicker patients: Consider stopping steroid 1 week before ? (not
likely) ACTH test ? Surgery in the AM Consult with physician Consider doing procedure in hospital setting Treat pain aggressively Monitor blood pressure Evaluate post-op for signs of adrenal insufficiency
(weak pulse, hypotension, dyspnea, myalgia, fever) Supplement steroid intraoperatively and Q8H for
24-48 hours
The Thyroid Produces T3 and T4 which regulate
the body’s metabolic rate and increase protein synthesis
The body is responsible for converting 80% of the T4 to T3 (more potent)
Carried in the blood by TBG Thyroid Binding Globulins
Regulation of SecretionS tress C o ld
Th yro idT3 T4
(th is req u ires iod in e )
A n te rio r P itu ita ryTS H
H yp oth a lm u sTR H
Th yro id R e leas in g H orm on e
Lab Tests sTSH the best test
Goiter – thyroid enlargement Euthyroid goiter is most common
form Iodine deficiency is the most
common form of goiter in the world Eating a lot of goitrogens
(cabbages, turnips, rutabagas) coupled with low iodine
Associated with also with hypo/hyperthyroidism
Hyperthyroidism
Autoimmune (Grave’s disease) Antibody against the thyroid TSH
receptor which results in continuous stimulation
Women more at risk
Other causes Overdose on thyroid medication Early stage thyroididits Pituitary disease
Symptoms of hyperthyroidism Nervousness, anxiety, heat intolerance,
fatigue, weight loss, palpitations, rapid heart beat, warm moist skin, rosy complexion, diarrhea, tremor
Myxedema puffy, raised red areas Opthalmopathy
Edema and inflammation of the extraocular muscles – does not resolve when patient treated
Wide stare, lid lag
Thyroid Storm - lethal More likely in patients with:
Goiter Eye pathology Long history of hyperthyroidism Poorly treated
Early symptoms Restlessness, fever, tachycardia, nausea, abdominal
pain,sweating, pulmonary edema Precipitants
Infections, trauma, surgical emergencies, operations Treatment
Medical help, hydrocortisone, IV glucose, ice packs
Hypothyroidism Hashimoto’s thyroiditis
Lymphocytic infiltration of the gland Decreased peripheral conversion of T4 to
T3 In ill or elderly
Congenital Other causes
Lithium Thyroiditis Iodine excess postablative
Symptoms of hypothyroidism Increased sensitivity to cold,
constipation, weight gain, weakness, dry coarse hair and skin, alopecia outer third of the eyebrows, puffy eyelids, hoarseness, moving/thinking slowly
Myxedema
Medical treatment - hypothyroidism T4 (L-thyroxin, Synthroid) is titrated
until the patient has a normal TSH May change insulin, coumadin
requirements If untreated, can progress to a
myxedema coma – progressive weakness, hypothermia, hypoglycemia, hypoventalation leading to death – it is treated with IV T4
Dental management - Hypothyroidism Recognize signs and symptoms Patients who are untreated or
incompletely treated are more sensitive to CNS depressants
Myxedematous coma can be precipitated by stress in severe, poorly treated elderly patients
Dental management - Hyperthyroidism Recognize signs and symptoms Patient untreated or incompletely
treated are very sensitive to epinephrine – do not administer
More likely to have osteoporosis Beware thyroid storm
Medical treatment - hyperthyroidism Propylthiouracil blocks the
extrathyroidal deiodination of T4 to T3
Betablockers like propranalol can treat tremors, sweating tachycardia
Subtotal thyroidectomy/radioactive iodine
Thyroid nodules Risk factors for cancer:
Young age Male History of neck irradiation Dyspnea, dysphagia Hard consistency Single nodule Rapid growth
Fine needle biopsy is best test