CORE - Endocrine Flashcards
Cerebriform adrenal gland(s)
adrenal hyperplasia
Salt-wasting in a boy
consider 21-hydroxylase deficiency CAH
Genital ambiguity in a girl
consider 21-hydroxylase deficiency CAH
Conn syndrome
increased aldosterone => hypertension, hypokalemia; most commonly due to a functional adenoma
Cushing syndrome
over-production of ACTH due to paraneoplastic syndrome, adrenal adenoma, or primary adrenal hyperplasia
Cushing disease
ACTH-secreting pituitary adenoma
Adrenal hemorrhage is most common on which side?
right
Nuclear medicine studies for diagnosis of pheochromocytoma
MIBG > octreoscan for adrenal pheo; octreoscan > MIBG for extra-adrenal pheo (paraganglioma)
Post-micturition syncope
bladder paraganglioma
Adrenal calcification DDx
old hemorrhage, ACC, myelolipoma (25%), neuroblastoma, TB, histoplasmosis, Wegener’s, melanoma mets
Formula for absolute washout
(enhanced - delayed) / (enhanced - unenhanced) * 100
Formula for relative washout
(enhanced - delayed) / (enhanced) * 100
Relative washout % for adrenal adenoma
> 40% washout
Absolute washout % for adrenal adenoma
> 60% washout
HU cutoff for adrenal adenoma on NECT
10 HU
Addison disease
adrenocortical insufficiency; autoimmune or post-infectious
Bilateral enlarged and calcified adrenal glands (peds)
Wolman disease; often fatal
Zuckerkandl tubercle
normal variant; projects from posterior aspect of lateral thyroid lobes
Location of recurrent laryngeal n. relative to thyroid gland
medial to Zuckerkandl tubercle
Thyroglossal duct cyst with an enhancing nodule + NEXT STEP
consider thyroid cancer; next step is biopsy
Enlarged thyroid gland DDx
multi-nodular goiter, Graves disease, iodine deficiency
TSH and T3/T4 in Graves disease
decreased TSH, increased T3/T4
Grave’s ophthalmopathy
order of involvement = I-M-S-L-O; painless, spares tendon insertions, increased intra-orbital fat
Dominant hyperechoic thyroid nodule(s)
Hashimoto’s thyroiditis (“white knight”)
Diffusely coarsened or nodular thyroid gland
Hashimoto’s thyroiditis
Delphian lymph nodes
adjacent to thyroid gland, level VI
Metastatic involvement of Delphian nodes
suggestive of metastatic laryngeal cancer
Reidel’s thyroiditis
assoc. with IgG-4; women 40-70 y/o; enlarged gland, fibrous replacement (T1/T2 dark)
Enlarged thyroid gland with low T1 and T2 signal
Riedel’s thyroiditis (fibrous replacement)
Granulmatous thyroiditis
a.k.a. de Quervain or subacute thyroiditis; due to viral infection, self-limited, painful; Tx is steroids
Lymphocytic thyroiditis
similar to subacute thyroiditis, except occurs post-partum and is painless
Most common type of thyroid cancer + 2nd most common type
papillary > follicular
Microcalcifications are most commonly assoc. with which type of thyroid cancer
papillary; microcalcifications may also be seen in nodal mets
Parathyroid adenoma imaging characteristics
early enhancement with delayed washout, T2 bright
Syndromes with increased risk of thyroid cancer
MEN 2 (medullary), Cowden (follicular), FAP/Gardner (papillary)
Calcitonin-producing type of thyroid cancer
medullary (assoc. with MEN 2)
Thyroid cancer types which respond poorly to I-131 therapy
medullary, anaplastic, Hurthle cell
“Pancake” adrenal gland
congenital absence of the ipsilateral kidney
Adrenal blood supply
superior suprarenal a. (from inferior phrenic a.), middle suprarenal a. (from aorta), inferior suprarenal a. (from renal a.)
Adrenal venous drainage
right suprarenal v. drains to the IVC, left suprarenal v. drains to renal v. or inferior phrenic v.
Adrenal zones
glomerulosa (aldosterone), fasciculata (cortisol), reticularis (androgens), medulla (catecholamines)
Triple stripe appearance of adrenal gland
normal in infants; hypoechoic cortex - hyperechoic medulla - hypoechoic cortex
Most common cause of excess cortisol
Cushing disease (pituitary adenoma)
Malignancy assoc. with increased ACTH production
small cell lung cancer
Clinical symptoms of Cushing disease/syndrome
moon facies, buffalo hump, central obesity, striae, thin skin
Causes of neonatal adrenal hemorrhage
breech birth or fetal distress (“stress”), congenital syphillis
Adrenal lesion equivocal for hemorrhage vs. neuroblastoma - NEXT STEP
short-term US follow-up (hemorrhage will get smaller)
Waterhouse-Friderichsen syndrome
post-hemorrhagic adrenal failure in the setting of N. meningitidis
Neuroblastoma typically arises from the adrenal cortex or medulla?
medulla
Pheochromocytoma imaging characteristics
T2 bright, heterogeneous enhancement
Pheochromocytoma assoc. syndromes
VHL, MEN 2 > NF1, tuberous sclerosis, Sturge-Weber, Carney triad
Carney triad
extra-adrenal pheochromocytoma (paraganglioma), pulmonary chondromas, GIST
Carney complex
cardiac myxomas, skin lesions; considered an MEN syndrome
Rule of 10’s
for pheochromocytoma; 10% extra-adrenal, 10% bilateral, 10% malignant, 10% in children, 10% familial, 10% not assoc. with hypertension, 10% contain calcification
Myelolipoma associations
Cushing’s, CAH, Conn’s
Most common mets to adrenal gland
breast, lung, melanoma; same as spleen
Adrenal lesion with signal loss on out-of-phase
adenoma; may be functional or non-functional
MEN 1
parathyroid hyperplasia, pituitary adenoma, pancreatic islet cell tumors
MEN 2a
medullary thyroid cancer, pheochromocytoma, parathyroid hyperplasia
MEN 2b
medullary thyroid cancer, pheochromocytoma, neuromas (mucosal or ganglioneuromas), marfanoid habitus
Flushing, diarrhea, pain, right heart failure, bronchospasm
carcinoid syndrome (liver mets)
Most common location for carcinoid
appendix > ileum
Collision tumor
mets to adrenal gland with a pre-existing adenoma (classically)
Suspicious features of thyroid nodules
solid, calcifications (esp. microcalcifications)
Thyroid nodule with comet tail artifact
colloid nodule
Most common location of ectopic thyroid tissue
lingual thyroid
Most common location for a thyroglossal duct cust
infrahyoid (per Radiopaedia)
RAIU % for Grave’s and multi-nodular goiter
> 70% for Graves, >40% for multi-nodular goiter
Risk assoc. with Hashimoto’s thyroiditis
increased risk of primary thyroid lymphoma
Antibodies assoc. with Hashimoto’s thyroiditis
anti-TPO, anti-thyroglobulin
Hyperthyroid => hypothyroid => euthyroid
subacute thyroiditis
Acute suppurative thyroiditis
bacterial infection of thyroid, may develop into an abscess
Cause of acute suppurative thyroiditis (peds)
may start in a 4th branchial cleft anomaly
Thyroid cancer type that mets hematogenously
follicular
Thyroid cancer type assoc. with prior radiation
anaplastic; seen in elderly patients
Papillary thyroid cancer mets
often cystic with microcalcifications
Origin of parathyroid glands
superior glands from 4th branchial pouch, inferior glands from 3rd branchial pouch
Most common cause of hyperparathyroidism
parathyroid adenoma
Typical age for ganglioneuroma
> 10 y/o
Laboratory test for pheochromocytoma
urine metanephrines/catecholamines (NE, Epi)
Lipid-poor adenoma
may be >10 HU on NECT and not demonstrate signal loss on out-of-phase MR
Indeterminant adrenal lesion after advanced imaging (CT/MR)
biopsy is indicated
Most common type of adrenal cyst
endothelial (lymphatic or angiomatous origin)
Adrenal cyst with peripheral calcification
pseudocyst (result of prior hemorrhage)
Most common location for an intra-abdominal paraganglioma
organ of Zuckerkandl (aortic bifurcation)
Adrenal cortical carcinoma - functional or non-functional?
may be either; functional ACC may produce excess aldosterone, cortisol, or androgens
Causes of adrenal hemorrhage (adult)
trauma, anticoagulation; may be bilateral; may cause hypotension
