Endocrine Flashcards
Glucagonoma
Tumor of the pancreatic a cells
4 Ds: dermatitis (necrolytic migratory erythema); diabetes (hyperglycemia), DVT, and depression
Insulinoma
- Episodic hypoglycemia and mental status changes that improve with glucose
- Have low glucose, high insulin, and high C peptide (indicating endogenous insulin production)
- Treat with surgical resection
Gatrinoma / Zollinger Ellision syndrome
- Gastrin producing tumor of pancreas of duodenum that results in treatment resistant peptic ulcers that can extend into jejunum
- Sx: abdominal pain, diarrhea (malabsorption)
- Test: exogenous secretin (S cells secreted in duodenum to decrease gastric acid sectretion) does not decrease gastrin levels
- Associated with MEN 1
Somatistatinoma
- Inhibits gastrin (results in acholhydria) and CCK which promotes contraction of the gall bladder (can lead to stone and steanorrhea)
VIPoma
Vasoactive peptide inhibits gastric acid secretion
Watery diarrhea, hypokalemia, and acholorhydria (WDHA syndrome - Watery Diarrhea, Hypokalemia, Acholorhydria)
Which structure connects the thyroid gland with the tongue?
thyroglossal duct
reminent in adult is the foramen cecum, a divot at the merge pt of the 3 parts of the tongue
How can you differentiate a thyroglossal duct cyst from a branchial cleft cyst?
TGD cyst is midline and motile (will move with swallowing), comes from patent thryoglossal duct
Branchial cleft cyst is lateral and derives from persistent cervical sinus
What are parafollicular cells in the thyroid dervied from and what cancer do they cause?
neuroendocrine cells
secrete calcitonin
cause medullary thyroid cancer (v aggressive)
What are the name of the carrier proteins that transport posterior pituitary hormones from the hypothalamus?
Neurophysins
GLUT 1
Non insulin dependent
Brain, cornea, RBCs
GLUT 2
liver, kidney, small intestine, beta islet cells
bi-directional
High Vmax, high Km
GLUT 3
Brain
GLUT 4
Insulin dependent (insulin upregulates their presence on cell surface) Muscle and adipose Low Km (high affinity), low Vmax
GLUT 5
fructose transporter
Spermatocytes, GI tract
What is another name for IGF-1?
Somatomedin C
What are the common causes of hypomagnesemia?
Diarrhea
Diuretics
Alcohol Abuse
Aminoglycosides (gentamycin, etc)
What are the effect(s) of magnesium on PTH?
1) Mild hypomagnesemia causes increase in PTH secretion
2) Gross hypomag causes decrease in PTH secretion
Which hormones use Gas receptors?
FSH, LH, ACTH, TSH [FLAT] CRH, GHRH PTH, calcitonin MSH ADH (V2) hCG
What hormones signal through cGMP?
ANP, BNP, NO (EDRF)
Think vasodilation
What hormones signal through Gq?
GnRH, Oxytocin, ADH (V1), TRH, Histamine (H1), Angiotensin II, Gastrin
What hormones signal via an intracellular receptor?
Cortisol, aldosterone, T3/T4, progesterone, estrogen, vitamin D
What hormones signal through an intrinsic tyrosine kinase receptor?
Insulin, IGF-1, FGF, PDGF, EGF
What hormones signal through a receptor associated tyrosine kinase?
Prolactin, Immunomodulators (IL2, IL6, etc), GH, G-CSF, EPO, TPO
Effects of Sex Hormone Binding Globulin Levels on Men and women
- Increase SHBG in men decreases free testosterone, gynocomastia
- Decreases in SHBG in women increase free testosterone, cause hirrsuitism
- Increase SHBG (women) due to pregnancy or OPCs do nothing, free estrogen levels unchanged
What are the classic signs associated with a neuroblastoma?
kid
Differences between neuroblastoma and willms tumor?
NB irregular, crosses midline
Wilms: renal tissue, smooth, never crosses midline, slightly older kids >4
What are pheos associated with?
MEN2A, MEN2B, neurofibromatosis type 1, von Hippel Lindau
What is the rule of pheos?
Rule of 10% Malignant Kids Calcify Extra-renal Bilateral
What is the pathonomonic presentation of congenital hypothyroidism?
"Cretinism" : 6 Ps, seen in kids Pot bellied Protruding umbilicus Pale Puffy faced Proturberant tongue Poor brain development
What are the pathnomonic cells seen in Hashimotos thyroiditis?
Hurthle cells
What is the pathonomonic finding of the histology in Graves disease?
Scalloping of the colloid
What are the pathonomonic findings in Papillary carcinoma (histology)?
Orphan annie eyed nuclei
Nuclear creases/ grooves
Psommoma bodies
(RET and BRAF mutation, kids radiation for acne)
What is unique about follicular carcinoma?
Hematogenous spread
What vitamin deficiency is associated with carcinoid tumors?
Niacin (B3) pellagra
Dermatitis, Diarrhea, Dementia
What breakdown product do you find in the urine in a patient with a carcinoid tumor?
5-HIAA (5-hydroxyindoleacetic acid)
What is the rule of 1/3 associated with carcinoid tumors?
1/3 metastisize
1/3 present with a second malignancy
1/3 are multiple
Most common malignancy in the small intestine
What is the progression of kidney pathology in DM?
mesangial expansion –> nodular glomerulosclerosis (KW nodules) + with thick basement membranes
What is tolbultamide and what is its main side effect?
first generation sulfonalurea (chlorpropamide)
Disulfram like reaction
Neuroblastoma key pts
MCC adrenal tumor in children
N-Myc
Homer Wright Rosettes
Firm, irregular mass that can cross the midline
Opthoclonus, myoclonus; HVA/VMA in urine, Bombesin, endolase + ,
Important disease that are AR inherited?
CF, phenylketonuria, thalasemia, sickle cell, lysosomal storage disease, infant polycystic kidney disease, and hemochromatosis
What is the mode of inheritance of the MEN diseases?
AD
HLA DR3 associations
DM1, Graves, Hashimotos, SLE
HLA DR4 associations
Rheumatoid arthritis, DM1
HLA DR5 associations
Hashimotos, pernicious anemia
What is the pathophysiology associated with bone pain due to primary hyperparthyroidism?
osteitis fibrosis cystica
lytic bone lesions filled with brown fibrosis from hemmorhage and hemosiderin pick up by macrophages
often seen in the jaw
What is the most common cause of hypopit in kids?
craniopharyngeoma
What cardiac abnormalities are associated with carcinoid tumors?
RIGHT SIDED HEART LESIONS
Tricuspid regurg, pulmonic stenosis
What are the common symptoms of hypoglycemia?
Lethargy, syncope, diplopia
Which cancers is bombesin a marker for?
Neuroblastoma; small cell lung cancer; gastric carcinoma, pancreatic carcinoma
From what cell line does a tumor that stains positive for Bombesin, neuron specific enolase, and chromogranin come from?
NEURAL CREST CELLS
What does the RET gene code for?
Tyrosine kinase receptors
