Endocrine Pathology Flashcards
euvolemic, Urinary volume > 3L/day ; hypernatremic
diabetes insipidus
would also have CNS symptoms
thurst caused by hypernatremia
dehydration + hypernatremia → thirst + neurologic sxs from high Na = brain cells shrink as H2O moves out (AMS, myoclonus, seizures, focal deficits, coma) caused by head trauma
What is this?
central diabetes insipidus
What are 3 causes of polyuria and polydipsia?
DM, DI, and psychogenic polydipsia
What is used to test diabetes insipidus vs diabetes meilits vs polyuria?
glucose levels
water depreivation for polyuria
desmopressin for central vs peripheral DI
in addition to genetic/congenital, head trauma/surgery, central diabetes insipidus can be caused by what?
tumor (craniopharyngioma, pituitary adenoma),
inflammatory (sarcoidosis, histiocytosis, meningitis),
vascular (aneurysm, infarction)
What is the hallmark of follicular adenoma?
benign proliferation of follicles surrounded by a FIBROUS CAPSULE!
What are the 4 types of thyroid carcinoma?
papillary carcinoma
follicular carcinoma
medullary carcinoma
anaplastic carcinoma
____ is the most common type of thyroid carcinoma
papillary (80%)
exposure to radiation as a child is greatest risk factor
which features define papillary carcinoma?
nuclear features and sommoma bodies (concentric calcification of papillary architecture - shows up as dark blue circular blobs on H+E cross sections
“nuclear groves” - blue line across nucleus (only visible in a few nuclei)
“orphan antihyde” nucleus - blue, granular, circular but center is usually clear
Where does papillary carcinoma of the tyroid usually spread to?
Cervical lymph nodes - but good prognosis!
What disorder does this describe?
Malignant prolliferation of thyroid follicles that are surrounded by a fibrous capsules and exhibit invasion through the capsule?
Follicular carcinoma
invasion of capsule is what differentiates from follicular adenoma - from there spread is hematogenous! Atypical for carcinomas which usually spread to the lymphnodes
T/F fine needle aspiration cannot differentiate between follicular adenoma vs carcinoma
true - only way to make distinction is to see the capsule.
What 4 carcinomas are exceptions to the general rule that carcinomas metastisize to the lymph?
Renal cell carcinoma - goes to renal vein
Hepatic cell carcinoma - hepatic vein
Follicular cell carcinoma (of the thyroid)
Choriocarcinoma
What are C-cells and what do they produce?
Parafollicular cells in thyroid - produce calcitonin
What type of thyroid carcinoma is associated with molignant proliferation of parafollicular C cells, hypocalcemia, and tumor deposition of amyloid’
“MALIGNANT CELLS IN AN AMYLOID STROMA”
Medullary carcinoma of the thyroid
C-cells produce high levels of calcitonin which normally inhibit renal excretion of Ca2+,
Large amounts of calcitonin produced from malignant proliferation of C-cells results in deposition within the tumor as amyloid (localized amyloidosis)
Histologically appears as island of malignant prolifferating homogeneous cells with heterochromatic nuclei and light blue/llight purple cytoplasm, surrounded by sea of pink “iceburgs”/ islands of amyloid (homogeneous - looks a little like colloid but not surrounded by follicular cells)
MEN 2A and 2B (MEN = multiple endocrine neoplasia) is associated with what?
MEN 2A : familial cases of medullary thryoid carcinoma
- due to a RET oncogene mutation
- (DO PROPHYLACTIC THYROIDECTOMY if detect RET mutation)
Also associated with pheochromocytoma and parathyroid adenoma
MEN 2B - medulary thyroid carcinoma, pheochromocytoma, and gangliall neuromas of oral mucosa
What type of tyroid carcinoma does this describe?
undifferentiated malignant tumor of thyroid that has ppor prognosis and usually is seen in elderly.
often invades local structures leading to dysphagia or respiratory compromise.
Anaplastic carcinoma
What thyroid condition is similar in appearance to anaplastic carcinoma?
Reidel fibrossing thryroiditis (which is chronic inflammation that results in extensive fibrosis resulting in hypothyroidism and “HARD AS WOOD” “NONTENDER” thyroid)
Similarities are that both invade local structures (fibrosis in the case of Riedel’s) causing dysphagia or respiratory compromise
DIFFERENCE IS AGE - Reidel’s is usually in 40’s (more often female) whereas ANAPLASTIC THYROID CARCINOMA IS IN ELDERLY
What does this describe?
chronic inflammation with germinal centers and Hurthle cells
High or low T vs TSH?
Hashimoto’s
low T, high TSH
What does this describe?
TENDER thyroid that follows viral infection
Subacute granulomatous (De Quervain) thyroiditis
- granulomatous inflammation can cause initial hyperthyroidism
- usually resolves on it’s own but if progresses causes HYPOTHYROIDISM
Which thyroid condition is associated with an increased B-cell lymphoma?
Hashimotos
What does this describe: chronic inflammation of the thyroid that results in extensive fibrosis resulting in hypothyroidism and “HARD AS WOOD” “NONTENDER” thyroid
Reidel fibrossing thryroiditis (which
HLA-DR5, antithyroglulin and antihyroid periodidase antibodies are associated with what disease?
Hashimotos - HLA-DR5 = autoimmune MHC-II subtype that get’s attacked by B-cells
What is the consequence of hypothyroidism in infants/neonates?
cretinism
What are the signs or cretinism?
infantile/neonate hypothyroidism, mental retardation, short stature, skeletal abnormalties, course facial features, enlarged tounge and umbilical hernia
High total free T4 and low TSH with downregulated TRH receptors is found in what disease?
Graves (auto-TSH IgG antibody stimulates TSH receptor - causes increased T3/T4 production, usually diffuse goiter, exopthalamus and myxedema)
Type II hypersensitivity Rxn.
Which tyroid disorder presents with “scalloping of colloid” on H&E
Graves - hypertrophy of colloid follicles with some whitish separation from follicular endothelial cells
What cell types regulate release of free ionized calcium?
Chief cells in the parathyroid glands through secretion of PTH
- increases bone osteoclast activity (BUT ACTUALLY SECONDARILY TO OSTEOBLAST ACTIVATION)
- Increases calcium and phosphate absorption from small intestine (indirectly via Vit. D)
- increases renal calcium reabsorption in the distal tubule
- decreases renal phosphate reabsorption in the proximal tubule (thus allowing more free ionized calcium - phosphate binds Ca2+)
What regulates PTH secretion?
FREE IONIZED (not total) serum calcium and (1,25 hydroxy) VD3 (renal derived)
Most common cause of primary hyperparathyroidims?
parathydoid adenoma (>80%)
usually involves only one gland (1/4)
What is nephrocalcinosis? What does it cause?
Complication of primary hyperparathyroidism
“metastatic calcification of renal tubules”
can cause renal insufficiency + polyuria
Depression and seizures are consequences of what type of parathyroid associated condition?
Primary hyperparathyroidism
Due to hypercalcemia! (can also manifest as psychosis)
What lab values would be expected from parathyroid adenoma leading to primary hyperparathyroidism?
increased PTH Increased Calcium Decreased phosphate Incrased urinary cAMP Increased serum alkaline phosphatase
Secondary hyperparathyroidism is associated with what change in free calcium?
Decreased free calcium
What is the pathogenisis of secondary hyperparathyroidism due to renal failure?
Renal insuficiency leads to decreased phosphate excretion
increased serum phosphate then binds free calcium and triggers chronically increased PTH secretion via the parathyroids
What is osteitis fibrosa cystica? What condition can it be associated with?
OFC=reabsoption of bone leading to fibrosis and cystic spaces in the bone
can be consequence of parathyroid adenoma and subsequent primary hypeparathyroidism and increased PTH
What is the consequence of chronic renal failure in terms of bone?
renal osteodystrophy - due to secondary hyperparathyroid hormone (decreased phosphate excretion leads to increased serum phosphate, binding and decrease of free calcium and increased PTH leads to bone re-absorption
Peptic ulcer disease, constipation and ______ can be caused by high calcium as a consequence of primary hyperparathyroidism
acute pancreatitis
What are the expected lab values for secondary hyperparathyroidism due to renal failure?
Increased PTH
Decreased serum calcium
Increased serum phosphate
increased alkaline phosphatase
What does this describe?
PTH —- High
Serum Calcium – Low
Serum phosphate — High
Short stature with moon facies and short 4th and 5th digit
Autosomal dominant pseudohypoparathyroidism (PTH end-organ resistance)
Albright’s hereditary osteodystrophy
Archibalds sign - “knuckle knuckle dimple dimple” on clenched fist
What is Kallmann syndrome?
Hypogonadotropic hypogonadism due to GRH deficiency associated with anosmia (inability to smell)
What is Laron syndrome?
dwarfism due to insensitivity to GH from mutated GH receptor
What disease is characterized by autoimmune destruction of the adrenal gland?
Addison’s disease
Mutation of GNAS1 gene leads to what condition?
pseudohyperparathydoidism (end organ resistance to PTH - High PTH, low calcium, high phosphate, low VD3)
