Endocrine II Flashcards
What causes Graves disease?
Autoimmune stimulation of the thyroid
What HLA markers are associated with Graves disease?
HLA-DR3
HLA-B8
What drugs are used to treat Graves disease?
Propylthiouracil (PTU)
Methimazole
What is the MoA of PTU?
Inhibits oxidation of I- (inhibits iodination of thyroglobulin)
Inhibits peripheral conversion of T4 to T3
What are the side effects seen with PTU?
Agranulocytosis
Liver dysfunction
What is the MoA of methimazole?
Inhibits oxidation of I- (inhibits iodination of thyroglobulin)
What are the side effects seen with methimazole?
Agranulocytosis
Fetal aplasia cubis (fatal scalp defect)
Fetal goiter
When is PTU used? When is methimazole used?
PTU is used in pregnant women for the first trimester
Methimazole is used any time other than in pregnant women during the first trimester
There are “hot nodules” in the thyroid. What is the likely diagnosis? What is the likely cause?
Toxic adenoma and multinodular goiter
D/t mutation in TSH receptor
When is iodine induced hyperthyroidism (Jod-Baselow Phenomenon) seen?
Increased iodine…like after contrast dyes are used
A patient comes in with a painful goiter and explains a course of hyperthyroid period to now being hypothyroid. What is the likely diagnosis? What causes it? Is it bad?
Subacute thyroiditis (de Quervain) d/t focal destruction of thyroid with granulomatous inflammation
De Quervain is usually self-limited
What is de Quervain associated with?
HLA-B35
Viral infection
How is a thyroid storm treated?
Beta-blocker
PTU or methimazole
Why are all babies screened for congenital hypothyroidism?
Because it can cause impaired physical/mental growth (and an enlarged tongue and enlarged/distended abdomen) and the symptoms can be avoided entirely
A patient presents with hypothryoid symptoms and a painless goiter. What should be on the differential?
Hashimoto thyroiditis (lymphocytic inflammation) B-cell lymphoma
What HLA subtypes are seen with Hashimoto thyroiditis?
HLA-DR5
HLA-B5
What is the biggest concern about a rock hard goiter?
Riedel’s thyroiditis can extend into the airway
Thyroid cancer is expected, and the cleared out cells and psammoma bodies are seen on biopsy. What is the likely diagnosis? What are some risk factors?
Thyroid papillary cancer…has a good prognosis
Tobacco use, radiation exposure, genetics (RET gene, BRAF gene)
Activation of a tyrosine kinase
Thyroid cancer is expected, and fibrous covered nodules are seen on a biopsy. What is the likely diagnosis? How can it spread? What are some associations?
Follicular carcinoma can spread hematogenously
Follicular carcinoma is associated with RAS mutation, PAX8-PPAR-gamma1 rearrangement
What is secreted from a medullary carcinoma? What is this cancer associated with?
Medullary carcinomas secrete calcitonin
MEN2A&B are associated with medullary carcinomas (RET mutation)
Tyrosine kinase activation
An old patient comes in with a new rock hard goiter. What is the likely diagnosis? Is this bad?
Anaplastic thyroid carcinoma is bad
Diabetes type I is associated with which HLA types?
HLA-DR3-DQ2
HLA-DR4-DQ8
Both on chromosome 6
Why are Schwann cells, lens, retina, and kidney most often damaged with diabetes?
These tissues don’t have sorbitol hydroxylase…after aldolase B converts glucose to sorbitol, it just stays in the cell…increasing the oncotic gradient
What causes DKA?
Various things create a state of excess glucagon, catecholamines and/or corticosteroids
