Endocrine Flashcards
Adrenal anatomy
Paired retroperitoneal above each kidney. If congenital absent kideny, adrenal takes on ‘pancake’ shape
Sup arterial from inf phrenic
Mid arterial from aorta
Inf arterial from renal artery.
Venous to IVC or L renal vein
Zona glomerulosa - aldosterone
Zona fasciculata - cortisol
Zona reticularis - androgens
Medulla - catecholamines
Triple stripe oreo appearance on USS in babies: hypoechoic cortex, hyperechoic medulla, hypoechoic cortex
Neuroblastoma
Form in adrenal medulla and typically look like elarged gland with hyperechoic component. Can also have cystic components and haemorrhage
Adrenal haemorrhage
Usually in trauma or stress. Enlarged gland with anechoic component
STRESS
Seen after breech birth but aso with fetal distress and congenital syphilis. Imaging diff depending on age of haemorhage but end result calcification. favours right side
TRAUMA
Adult in setting of trauma. More common in setting of trauma
Wterhouse Friderichsen Syndrome - haemorrhage in setting of meningitis
Hyperplasia
Big adrenal, looks like a brain with wrinkled surface. Longer than 20mm and limb thicker than 4mm
21 HYDROXYLASE DEFICIENCY
If stem mentions genital ambiguity then this is answer. results in congenita adrenal hypertrophy. Genital ambiguity in girls and salt losing in boys
TOO MUCH CORTISOL
Overproduction of ACTH resulting in bilateral adrenal gland hyperplasia.
Cushing disease is overproduction by pituitary adenoma, most common cause 75%
Cushing syndrome is variety of causes with common symptoms such as ACTH secreting tumour usually lung SCC. or overproduction b adrenaladenoma or high dose steroids
Adrenal adenoma
Most common adrenal tumour, 8% people.
NON CON
<10HU
CONTRAST
Delayed/non-con x 100. If >60% is adenoma
Enhanced-delayed/enhanced x 100. If >40% is adenoma
Hypervascular mets can mimic adenoma. If HU >120 should think met. Phaeochromocytomas can also mimic if HU >120 arterial or PV
MRI want to see drop out on in and out of phase
Adrenal lesion tricks for exam
Adenomas usually homogenous. If haemorrage, calcs, necrosis think about other things
Adenomas usually <3cm. Bigger mass more likely to be malignant with exception of bluk fat myelolipomas or phaeos
Bilateral small probably adenomas
Bilateral large
Bilateral large phaeo or met
PV >120HU probably met RCC/HCC or phaeo
Collision tumour
Two different tumours smash together, usually one an adenoma. PET and MRI can usually differentiate.
Conns syndrome
Syndrome of excessive aldosterone production. Most commonly from benign adenoma. Cortical carcinoma a possibility but much more rare.
Phaeochromocytoma
Large at presentation >3cm. Look is variable (heterogenous, homogenous, cystic areas, calcs, sometimes fat).
CLassic is heterogenous mass with avid enhancement.
MRI T2 bright. MIBG uptake. Can be extra adrenal suchs as organ of Zuckerkandl along aorta around IMA
Remember to check on any phase, if >120 not an adenoma.
RULE OF 10s 10% extra-adrenal 10% bilateral 10% in children 10% hereditary 10% NOT active
SYNDROMES
VHL, MEN2a and 2b
Can be in NF1, Sturge Weber and TS
CARNEY TRIAD
Extra adrenal phaeo, GIST, Pulmonary hamartoma
Adrenal myelolipoma
Benign tumour that contains bulk fat. 1/4 have calcs
If big they can bleed and present with retroperitoneal haemorrhage.
Asociated with: Cushings, Conns, CAH
Can result in discontiuous diaphragm artefact on USS
Miscellaneous
ADRENAL CYST
Often unilateral and can be any size. Thin wall, no enhancement.
METS
Breast, lung and melanoma. No specific findings, look like lipid poor adenoma.
CALCs
Often prior trauma or infection. Melanoma mets calcify Certain tumours (cortical carcinoma, neuroblastoma, myelolipoma)
CORTICAL CARCINOMA
Large 4-10cm. Can be functionsl (Cushings). Calcify 20%. Bad and met everywhere. Unlikely to be <5cm. Often has central necrosis.
WOLMAN DISEASE
Aunt Minnie. Bilateral enlarged calcified adrenals. Fatal in first year of life.
Multiple Endocrine Neoplasia (MEN)
MEN1 (3 Ps)
Pituitary denoma
Parathyroid hyperplasia
Pancreatic Tumours
MEN 2a (1M 2P)
Medullary thyroid Ca
Phaeochromocytoma
Parathyroid hyperplasia
MEN 2b (2Ms 1P)
Medullary thyroid Ca
Marfanoid Habitus and Mucosal Neuroma
Phaeochromocytoma
Carcinoid syndrome
Flushing, diarrhoea, pain, right heart failure from seretonin manufactured by carcinoid tumour. Does not occur until mets to liver.
Typical location for primary is GIT 70%, usually distal ilium. Syndrome only occurs in 10% cases
GI carcinoids are associated with other GI tumours like adeno
Urine test for carcinoid is 5HIAA. Octreotide scan is scan of choice.
MIBG is always positive. Systemic seretonin degrades heart valves and causes tricuspid regurg
Von Hippel Lindau
Hemangioblastoma (retina, cerbeellum, spinal cord)
Endolymphatic Sac Tumour (ELST) 10%
Bilaterl Clear Cell RCC (VHL clear cell) 70%
Papillary cystadenoma epididymis 55%
Phaeochromocytoma 10%
Pancreatic cysts and serous cystadenomas 75%
PGL Syndrome (paraganglioma and Phaeochromocytoma)
Multiple head and neck paraganglioma 70%
Phaeochromocytoma risk variable depending on subtype
