Hyperthyroidism And Hypothyroidism Flashcards
What are the signs and symptoms of hyperthyroidism
Heat intolerance Weight loss despite increased appetite Exophthalmos/Proptosis Lid lag Lid retraction Increased sweating Thinning hair, thin and silky skin Restlessness, irritability, anxiety Hyperkinesis Wakefulness Tremor Increased muscle tone Increased cardiac output Tachycardia Palpitations Dyspnoea Diarrhoea Increased BMR Increased sensitivity to catecholamines Decreased plasma cholesterol
What are the congenital causes of primary hypothyroidism?
Thyroid agenesis
Ectopic thyroid
Synthetic defects
List the defects of hormone synthesis that can cause hypothyroidism.
Iodine deficiency
Dyshormonogenesis
Antithyroid drugs
Other drugs (lithium, amiodarone, interferon)
List the autoimmune causes of hypothyroidism.
Atrophic thyroiditis
Hashimoto’s thyroiditis
Postpartum thyroiditis
Name one infective cause of primary hypothyroidism.
Post-subacute thyroiditis
What are the post-surgical causes of hypothyroidism?
Radioactive iodine therapy
External neck irradiation
Tumor
What are the causes of secondary hypothyroidism
TSH deficiency
TRH deficiency
What are the common causes of hyperthyroidism?
Graves’ disease P
Toxic multinodular goiter P
Solitary toxic nodule/adenoma P
List the uncommon causes of hyperthyroidism.
Acute thyroiditis (viral, autoimmune, post-irradiation, postpartum) Gestational thyrotoxicosis S Neonatal thyrotoxicosis Exogenous iodine Drugs (amiodarone) Thyrotoxicosis factitia P
What are the rare causes of hyperthyroidism?
TSH-secreting pituitary tumors S
Metastatic differentiated thyroid carcinoma
HCG-producing tumors
Hyperfunctioning ovarian teratoma P
What is Grave’s disease?
An autoimmune disorder characterized by abnormal stimulation of the thyroid gland by TSHR-Ab’s
What are the clinical manifestations of Graves’ disease?
Thyrotoxicosis (diffuse goiter)
Exophthalmos
Pretibial myxedema
What other autoimmune disorders is Graves’ disease associated with?
Pernicious anaemia
Myasthenia gravis
Also associated with HLA-DR3/5 and HLA-B8
Familial tendency is evident
Describe the micropathological appearance of Graves’ disease
Scanty colloid
Packed follicles with tall columnar epithelium
Scattered lymphocytes
It’s has a pseudo-papillary growth pattern
Define Hashimoto’s thyroiditis
Also known as chronic autoimmune thyroiditis. It is caused by an autoimmune process directed against the thyroid gland. It is the most common cause of hypothyroidism in adults and of goiter in women.
What are the clinical manifestations of Hashimoto’s thyroiditis?
Goiter, non-tender
Rarely, a transient sub clinical hyperthyroidism.
What disorders is Hashimoto’s thyroiditis associated with?
SLE Sjogerns Rheumatoid Arthritis Pernicious Anaemia DM Graves' disease
Describe the pathological microscopic appearance of Hashimoto’s thyroiditis
Lymphocytic infiltration
Scattered follicles
Hurthle cells
Fibrosis
Describe the macroscopic pathological appearance of Graves’ disease
Diffusely enlarged thyroid gland, red, cut surface resembles pancreas
Prominent vascularity
Describe the macroscopic pathological appearance of Hashimoto’s thyroiditis
Diffuse, symmetrical enlargement of thyroid gland
Firm, rubbery, pale grey
What are the complications of Hashimoto’s thyroiditis?
Hypothyroidism
Lymphoma
Papillary Carcinoma
What would the TSH and T4 results be in primary hypothyroidism?
High TSH
Low T4
What would the lab results be of secondary hypothyroidism?
Low TSH and T4
What would the lab results be of primary hyperthyroidism?
Low TSH
High T4
What would the lab results be of secondary hyperthyroidism?
High TSH and T4
What are the signs and symptoms of hypothyroidism?
Cold intolerance Weight gain despite decreased appetite Decreased sweating Coarse, dry skin and hair Myxedema Deep/Hoarse voice Impaired growth (child) Mental retardation (child) Mental and physical sluggishness Somnolence Decreased muscle tone and reflexes Decreased cardia output Bradycardia Hypoventilation Constipation Decreased BMR Decreased sensitivity to catecholamines Increased plasma cholesterol
