Thyroid Disorders

Mere som dette

ANTIBODY AND ANTIGEN

af Yolanda Soto

shp2

af yu ho

Tissue Repair

af Chan Samuel

Immunology

af Ravi Chacko

Thyroid Disorders

Hypothyroidism

• low TSH
• low FT4

Pituitary Insufficiency

• High TSH
• Normal FT4

• high TSH
• low FT4

Iatrogenic

Medications

Amiodarone

• antiarrhymthic drug decreases T4 to T3 conversion and can casue inflammatory thyroiditis

Lithium

• drug for bipolar disorder inhibits thyroid hormone synthesis and release

Aspirin and Sulfonamide can induce thyroiditis

Radioactive Iodine Ablation

• treatment for hyperthyroidism or thyroid cancer

Congenital

• cretinism
• protruding umbilicus
• pale skin
• puffy face
• pot belly
• protruding tongue
• poor neuro development

Iodine Deficiency

most common congenital cause in developing countries

Autoimmune maternal hypothyroidism

Fetal thyroid agenesis

• most common congenital cause in US

Riedel Thyroiditis

• rare
• rock hard goiter, no pain
• develops as response to chronic inflammation
• normal thyroid parenchyma replaced by dense fibrous tissue with an inflammatory infiltrate
• associated with IgG4-related diseases
• may lead to compressive symptoms
• impinge on trachea
• interfere with breathing
• hoarseness

-painless goiter

-often as asymptomatic as Hashimoto

-anti-TPO and TGB antibodies

-50% transient with full recovery; 50% develop permanent hypothyroidism

Postpartum

Subacute granulomatous (de Quervain)

-painful goiter

-self limited with recovery after few weeks

-precipitated by viral infection

-symptoms of hyperthyroidism

-pain managed with NSAIDs or corticosteroids

-inflammation of thyroid and sudden release of thyroglobulin

Hashimoto's Thyroiditis

• 2% of US
• most common
• Autoimmune disease
• Anti-TPO, anithyroglobulin, antimicrosomal immunoglobulin G (IgG)
• personal/family history
• more common in women
• HLA subtypes DR3 and DR5
• Lymphocitic infiltration with Hurthle cells
• smooth, nontender, goiter
• firm, nonpitting edema in legs (pretibial myxedema)
• risk of pernicious anemia

Eurthyroid

Single Nodule (thyroid neoplasm)

Multicellular Goiter

Hyperthyroid

Subclinical

-Low TSH

-Normal FT4

-at risk for hypothyroidism

Secondary

-High TSH

-High FT4

Pituitary Adenoma

-overproduction of TSH secretion by pituitary gland

-stimulates thyroid to produce T3/T4

Primary

-Low TSH

-High FT4

Diffuse Uptake Scan

Grave's Disease

• 80% of cases
• family history, autoimmune condition
• smooth diffuse goiter
• Type 2 hypersensitivity reaction
• HLA subtypes B8 and DR3
• Anti-TSH receptor antibodies (IgG)
• thyroid biopsy
• diffuse hypertrophy and hyperplasia
• more crowded
• vascular congestion
• pretibial myxedema
• Exophthalmos positive

Hot Nodules/Nodular Scan

Toxic multinodular goiter

• uncommon
• Plummer's Disease
• seperate nodules develop throughout gland
• follicular cells distended with colloid in uneven or patchy manner

Toxic Follicular Adenomas

uncommon

Reduced Scan

Exogenous

Nonthyroid Secretion of Thyroid Hormone

• rare ovarian tumor struma ovarri
• monodermal teratoma
• mature thyroid tissue

Factitious Thyrotoxicity

-drugs used to treat hypothyroidism for weight loss

-also suppress TSH

-Low TSH, elevated T3/T4

Thyroiditis

Autoimmune

Silent lymphocytic

-painless goiter

-often as asymptomatic as Hashimoto

-50% transient with full recovery; 50% develop permanent hypothyroidism

Pospartum

-transient, self-limited variant of hashimoto

Infectious

Subacute Granulomatous (de Quervain) thyroiditis

-painful goiter

-self limited with recovery after few weeks

-precipitated by viral infection

-symptoms of hyperthyroidism

-pain managed with NSAIDs or corticosteroids

-inflammation of thyroid and sudden release of thyroglobulin

-second most common type