Hypothyroidism & Thyroiditis Flashcards by Impo Unknown

Primary hypothyroidism

It is caused by intrinsic dysfunction of the thyroid gland leading to hormone deficiency.

How well did you know this?

Not at all

Perfectly

Definition of overt hypothyroidism

Elevated TSH above 10 mIU/L with free T4 below normal.

How well did you know this?

Not at all

Perfectly

Definition of subclinical hypothyroidism

Modestly elevated TSH with free T4 in the low-normal range.

How well did you know this?

Not at all

Perfectly

Most common cause of primary hypothyroidism

Autoimmune thyroiditis including Hashimoto’s and atrophic thyroiditis.

How well did you know this?

Not at all

Perfectly

Iatrogenic causes of hypothyroidism

Radioiodine therapy subtotal or total thyroidectomy and neck irradiation.

How well did you know this?

Not at all

Perfectly

Drugs that cause hypothyroidism

Amiodarone lithium iodine-containing contrast and antithyroid drugs.

How well did you know this?

Not at all

Perfectly

Two types of transient hypothyroidism

Silent thyroiditis and subacute thyroiditis.

How well did you know this?

Not at all

Perfectly

Common causes of secondary hypothyroidism

Pituitary tumors surgery irradiation or infiltrative disorders.

How well did you know this?

Not at all

Perfectly

Common causes of hypothalamic hypothyroidism

Tumors trauma infiltrative diseases or idiopathic causes.

How well did you know this?

Not at all

Perfectly

Definition of autoimmune hypothyroidism

Hypothyroidism caused by immune-mediated thyroid destruction.

How well did you know this?

Not at all

Perfectly

Goitrous autoimmune hypothyroidism

Also called Hashimoto’s thyroiditis.

How well did you know this?

Not at all

Perfectly

Atrophic thyroiditis

Late stage of autoimmune hypothyroidism with minimal residual thyroid tissue.

How well did you know this?

Not at all

Perfectly

Subclinical autoimmune hypothyroidism

Normal T4 maintained by elevated TSH with minor symptoms.

How well did you know this?

Not at all

Perfectly

Clinical or overt hypothyroidism

TSH >10 mU/L with decreased unbound T4 and apparent symptoms.

How well did you know this?

Not at all

Perfectly

Histological features of Hashimoto’s thyroiditis

Lymphocytic infiltration germinal centers thyroid atrophy and fibrosis.

How well did you know this?

Not at all

Perfectly

Histological difference in atrophic thyroiditis

More extensive fibrosis with fewer lymphocytes and absent thyroid follicles.

How well did you know this?

Not at all

Perfectly

Genetic factors in autoimmune hypothyroidism

Increased risk in siblings and linkage with other autoimmune diseases.

How well did you know this?

Not at all

Perfectly

Autoimmune diseases linked to hypothyroidism

Type 1 diabetes Addison’s disease pernicious anemia and vitiligo.

How well did you know this?

Not at all

Perfectly

Common symptoms of hypothyroidism

Fatigue cold intolerance dry skin and weight gain.

How well did you know this?

Not at all

Perfectly

Neurological symptoms of hypothyroidism

Difficulty concentrating poor memory and impaired hearing.

How well did you know this?

Not at all

Perfectly

Gastrointestinal symptoms of hypothyroidism

Constipation and poor appetite.

How well did you know this?

Not at all

Perfectly

Respiratory symptoms of hypothyroidism

Dyspnea and hoarse voice.

How well did you know this?

Not at all

Perfectly

Menstrual changes in hypothyroidism

Menorrhagia followed by oligomenorrhea or amenorrhea.

How well did you know this?

Not at all

Perfectly

Common signs of hypothyroidism

Puffy face dry skin alopecia bradycardia and peripheral edema.

How well did you know this?

Not at all

Perfectly

Neurological sign of hypothyroidism

Delayed tendon reflex relaxation.

Hand disorder associated with hypothyroidism

Carpal tunnel syndrome.

Laboratory abnormalities in hypothyroidism

Anemia hyponatremia hypoglycemia and high cholesterol.

ECG finding in hypothyroidism

Sinus bradycardia with low voltage in limb leads.

Imaging finding in hypothyroidism

Pericardial effusion on chest X-ray and echocardiography.

Primary hypothyroidism diagnosis

Elevated TSH with low free T4.

Subclinical hypothyroidism diagnosis

Elevated TSH with normal free T4.

Central hypothyroidism diagnosis

Normal or low TSH with low free T4.

Treatment goal in hypothyroidism

Replace thyroid hormone while avoiding thyrotoxicosis.

Drug of choice for hypothyroidism

Levothyroxine sodium.

Levothyroxine dosage in adults

1.8 mcg/kg/day.

Levothyroxine dosage in elderly

1.0 mcg/kg/day due to reduced clearance.

Higher levothyroxine dose required in

Postsurgical or postablative hypothyroidism.

Definition of myxedema coma

Severe hypothyroidism with hypothermia bradycardia hypotension and altered mental status.

Risk factors for myxedema coma

Advanced age poor healthcare access and major organ diseases.

Immediate treatment for myxedema coma

IV thyroxine 50-100 mcg every 6-8 hours for 24 hours.

Supportive treatment in myxedema coma

Intensive care for hypoventilation and hypotension.

Additional hormone used in severe cases

Triiodothyronine in divided doses.

Adrenal support in myxedema coma

IV hydrocortisone 50 mg every 8 hours to prevent adrenal crisis.

Acute thyroiditis

It is caused by bacterial or fungal infections or radiation exposure.

Common bacterial causes of thyroiditis

Staphylococcus Streptococcus and Enterobacter.

Common fungal causes of thyroiditis

Aspergillus Candida Coccidioides Histoplasma and Pneumocystis.

Cause of radiation thyroiditis

131I treatment.

Subacute thyroiditis causes

Viral infections and silent thyroiditis including postpartum thyroiditis.

Chronic thyroiditis causes

Autoimmunity and parasitic infections.

Autoimmune causes of thyroiditis

Hashimoto’s thyroiditis atrophic thyroiditis and focal thyroiditis.

Parasitic causes of thyroiditis

Echinococcosis strongyloidiasis and cysticercosis.

Cause of transient thyrotoxicosis in subacute thyroiditis

Uncontrolled leakage of thyroid hormone.

Typical duration of thyrotoxicosis in subacute thyroiditis

2 to 8 weeks.

Outcome after thyrotoxicosis in subacute thyroiditis

Transient hypothyroidism followed by recovery.

Hallmark symptoms of subacute thyroiditis

Painful thyroid enlargement systemic inflammation and transient thyrotoxicosis.

Pain location in subacute thyroiditis

Thyroid throat ears or jaw.

Constitutional symptoms in subacute thyroiditis

Fever chills sweats and malaise.

Thyroid gland characteristics in subacute thyroiditis

Tender enlarged and woody hard.

Differential diagnoses for thyroid pain

Acute thyroiditis hemorrhage into a nodule and rapidly growing thyroid cancer.

Laboratory findings in subacute thyroiditis

Overt thyrotoxicosis with high T4 and elevated ESR.

First-line treatment for subacute thyroiditis pain

High-dose aspirin or naproxen sodium.

Second-line treatment for subacute thyroiditis

Glucocorticoids tapered over several weeks.

Treatment for transient thyrotoxicosis

Short-term β-blockers for 1 to 3 weeks.

Treatment for symptomatic hypothyroidism in subacute thyroiditis

Short-term thyroxine replacement.

Most common population affected by lymphocytic thyroiditis

Postpartum women.

Percentage of postpartum women affected by lymphocytic thyroiditis

Up to 6%.

Predisposing factors for lymphocytic thyroiditis

Prior postpartum thyroiditis type 1 diabetes and antithyroid antibodies.

Phases of lymphocytic thyroiditis

Transient thyrotoxicosis followed by transient or persistent hypothyroidism.

Typical duration of thyroid dysfunction in lymphocytic thyroiditis

2 to 8 weeks.

Management of lymphocytic thyroiditis

Observation and reassurance.

Symptomatic treatment for thyrotoxicosis in lymphocytic thyroiditis

Short-term β-blocker therapy.

Hypothyroidism & Thyroiditis Flashcards

(72 cards)