Transcript ADRENAL AND THYROID DISORDERS

ADRENAL AND THYROID
DISORDERS
Claire Nowlan MD
Jan 9, 2004
The Adrenal Glands
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Medulla - part of the sympathetic nervous
system
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produces epinephrine and norepinephrine
Cortex produces:
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1) Aldosterone (a mineralcorticoid)– acts mainly
on the cells of the kidney tubules
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Regulation of plasma salts – Na and K
Blood pressure
Blood volume
2) Androgen and Estrogen
The Adrenal Cortex
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3) Cortisol (a glucocorticoid)
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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
stress
Hypothalmus
CRH
corticotropin-releasing hormone
Anterior pituitary
ACTH
Adrenal Cortex
Cortisol
Synthetic glucocorticoids
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Most common ones are prednisone,
methylprednisone, dexamethasone.
Used to decrease inflammation in :
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Rheumatoid arthritis, SLE, asthma, inflammatory
bowel disease, organ transplantation
Long term side effects include
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Hypertension, osteoporosis, diabetes, glaucoma,
delayed wound healing, peptic ulcers
Hyperadrenalism
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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
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Primary (problems
with adrenal gland)
“Addison’s disease”
Etiology includes
autoimmune, Tb or
HIV infections,
metastatic
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Secondary
Etiology includes
excess steroid
administration or
pituitary/
hypothalmus
problems
Hypoadrenalism
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Acute adrenal insufficiency is a medical crisis
Chronic disease usually presents with vague
complaints
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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
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Difficult to do
24 hour urine cortisol
ACTH suppression test
Medical management
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Hyperadrenalism
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Surgery/radiotherapy to destroy
pituitary/adrenal tumour
Ketoconazole inhibits adrenal hormone
biosynthesis
Hypoadrenalism
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Supplement mineralcorticoids, glucocorticoids
Avoid ketoconazole, P450 inducers (rifampin,
phenytoin, barbituates
In surgery tx same as patient on steroids
Dental management
Patients on steroids hyperadrenalism
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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
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Determine length of time steroid taken
Determine dose of steroid
For routine/minimally invasive
procedures
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Ensure patient has taken regular steroid
dose – preferably within 2 hours of
procedure
For major procedures
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Using general anesthesia, 1+ hours,
significant blood loss, in sicker patients:
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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
The Thyroid
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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 Secretion
Stress Cold
Hypothalmus
TRH
Thyroid Releasing Hormone
Anterior Pituitary
TSH
Thyroid
T3 T4
(this requires iodine)
Lab Tests
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sTSH the best test
Goiter – thyroid enlargement
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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)
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Antibody against the thyroid TSH receptor
which results in continuous stimulation
Women more at risk
Other causes
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Overdose on thyroid medication
Early stage thyroididits
Pituitary disease
Symptoms of hyperthyroidism
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Nervousness, anxiety, heat intolerance,
fatigue, weight loss, palpitations, rapid heart
beat, warm moist skin, rosy complexion,
diarrhea, tremor
Myxedema puffy, raised red areas
Opthalmopathy
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Edema and inflammation of the extraocular muscles –
does not resolve when patient treated
Wide stare, lid lag
Thyroid Storm - lethal
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More likely in patients with:
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Early symptoms
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Restlessness, fever, tachycardia, nausea, abdominal
pain,sweating, pulmonary edema
Precipitants
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Goiter
Eye pathology
Long history of hyperthyroidism
Poorly treated
Infections, trauma, surgical emergencies, operations
Treatment
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Medical help, hydrocortisone, IV glucose, ice packs
Hypothyroidism
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Hashimoto’s thyroiditis
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Decreased peripheral conversion of T4 to T3
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Lymphocytic infiltration of the gland
In ill or elderly
Congenital
Other causes
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Lithium
Thyroiditis
Iodine excess
postablative
Symptoms of hypothyroidism
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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
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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
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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
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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
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Propylthiouracil blocks the
extrathyroidal deiodination of T4 to T3
Betablockers like propranalol can treat
tremors, sweating tachycardia
Subtotal thyroidectomy/radioactive
iodine
Thyroid nodules
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Risk factors for cancer:
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Young age
Male
History of neck irradiation
Dyspnea, dysphagia
Hard consistency
Single nodule
Rapid growth
Fine needle biopsy is best test