UNIT 5: ENDOCRINE
Hypothyroidism
Group A
Hypothyroidism
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Background:
Primary hypothyroidism - Most common cause is HASIMOTO’S
THYROIDITIS diagnosed in >80% of cases – is an autoimmune disease
Secondary hypothyroidism - <5% cases due to deficient pituitary
production of TSH
Prevalence 3x higher in women compared to men
Annual incidence rate 1-2 per 1,000 women
Presentation of symptoms in elderly may be atypical or absent
Prevalence increases with age
Caucasians higher incidence than non-Caucasians
Risks:
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Risks highest in persons with:
Type 1 diabetes mellitus
Family history of thyroid disease
History of head/neck cancers treated with radiation therapy
Previous radioactive iodine treatment
Previous thyroid surgery
Case:
Mr. T. presents to you concerned about her weight gain and fatigue. Both
of these problems have been problems for years. Recently, a friend
told her these problems may be because her thyroid is not working
properly and she wants to have her thyroid checked.
What other signs and symptoms would you ask Ms. T. about?
What other signs and symptoms would you ask Ms. T.
about?
Clinical Signs and Symptoms
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Fatigue (reported by this patient)
Cold intolerance
Constipation
Impaired memory
Slowed mentation
Depression
Ataxia
Muscle weakness
Muscle cramps
Clinical Signs & Symptoms Continued
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Menstrual disturbance
Hoarseness
Goiter
Periorbital edema
Weight gain (was reported by this patient)
Ask about family history:
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Personal or family history of associated autoimmune disorders:
Pernicious anemia
Adrenal insufficiency
Diabetes mellitus Type 1
Ovarian failure
Celiac disease
Sjogren’s syndrome
Multiple sclerosis
Ask about previous thyroid injury or treatment
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Thyroidectomy or other neck surgery
Radioactive iodine therapy
External radiation therapy
Ask about current medications
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Drugs that impair thyroid function:
Lithium
Amiodarone
Aminoglutethmide
Interferon a
Thalidomide
Betaroxine
Stavudine
Ask about pituitary disorders
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Pituitary tumor
Signs of sellar mass: headache, bi-temporal hemianopsia or
diplopia
History of pituitary surgery or radiotherapy
History of head trauma
References:
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Roberts, C. G., & Ladenson, P. W. (2004). Hypothyroidism.
Lancet, 363, 793-803.
Clinical practice guideline: Investigation and Management of
Primary Thyroid Dysfunction. (2008). Retrieved February 1,
2009 from
http://topalbertadoctors.org