Absite review (2) Flashcards
Arterial supply and vascular drainage of adrenal gland
- Superior adrenal – inferior phrenic artery
- Middle adrenal – aorta
- Inferior adrenal – renal artery
- Left adrenal vein goes to left renal vein.
- Right adrenal vein goes to inferior vena cava
Lymphatic drainage of adrenal medulla
Lymphatics drain to subdiaphragmatic and renal lymph nodes.
GFR zones of adrenal cortex
SALT, SUGAR and SEX STEROIDS
cortisol effect
inotropic, chronotropic, and increases vascular resistance; proteolysis and
gluconeogenesis; decreases inflammation, glycogenolysis
Aldosterone secretion is stimulated by
1.angiotensin 2
2. hyperkalmeia
3. to some extent ACTH
which CAH is salt wasting
21-hydroxylase deficiency
which CAH has low testesterone
17-hydroxylase deficiency
MC cause of primary hyperaldosteronism (Conn’s syndrome)
bilateral idiopathic adrenal hyperplasia
(Renin is low)
Causes of secondary adrenal hyperplasia
CHF, Renal artery stenosis, Renin secreting tumor…etc
(Renin is high)
patient with HTN and hypokalemia u think of
Hyperaldosternism (Conn’s syndrome)
Dx for primary hyperaldosteronism
- Salt-load suppression test (best, urine aldosterone will stay high)
- Aldosterone:renin ratio > 25
MCC of hypocortisolism (addison disease)
withdrawal of exogenous steroids
Cosyntropin test
give ACTH and measure cortisol level
hypotension not responding to fluids or pressors think of
Acute adrenal insufficiency
MC cause of hypercortisolism (cushing’s syndrome)
Exogeneous steroid intake
best test to diagnose cushing syndrome
24- hour urinary cortisol level (best) , ACTH
high dose dexamethasone suppression test effect on ectopic producer of ACTH
does not suppress
cushing’s disease (not syndrome) refers to
pituitary adenoma
MC noniatrogenic cause of hypercortisolism
pituitary adenoma
rate limiting enzyme in catecholamines production
tyrosine hydroxylase
enzymes that converts norepinephrine into epinephrine is only found in
adrenal medulla
MC location of extraadrenal neural crest tissue
usually in the retroperitoneum,
most notably in the organ of Zuckerkandl at the aortic bifurcation.
10% rule of pheochromocytoma
malignant, bilateral, in children, familial, extra-adrenal
preoperative management in pheochromocytoma
good volume resuscitation
give alpha blocker before beta blocker
Most common extramedullary tissue site for pheochromocytoma
organ of Zuckerkandl
superior and middle thyroid veins drain
internal jugular vein
inferior thyroid vein drain
innominate (brachiocephalic vein)
MC injured nerve following thyroidectomy
superior laryngeal nerve
Tubercles of Zuckerkandl of thyroid
most posterio-lateral extension of thyroid gland
thyroglobulin function
stores T3 and T4 in colloid within follicular cells
Thyroxine binding protein function
transport protein that binds most of T3 and T4 in plasma
Wolf-Chaikoff effect
patient given high doses of iodine
(Lugol’s solution, potassium iodide) ihbit T3 and T4 release
(used in Thyroid Storm)
Most thyroid nodules are benign (T or F)
true
best initial test for thyroid nodules
FNA and TFT
nodules that warrant FNA (according to size)
nodules 5mm or more
colloid tissue on thyroid nodule FNA, whats next
most likely colloid goiter; low chance of malignancy (< 1%)
* Tx: thyroxine; lobectomy if it enlarges
normal thyroid tissue on FNA with elevated TFT most likely
solitary toxic nodule
MCC of goiter worldwide
iodine deficiency
Most important aspect before removal of a lingual thyroid
Is the only thyroid tissue in 70% of patients who have it
what hyperthyroid medication is safe in pregnancy
PTU
methimazole and PTU MOA
Inhibits peroxidases and prevents iodine–tyrosine coupling
causes of hyperthyroidism
- Graves disease (MC)
- Toxi multinodular goiter
3.single toxic nodule
symptoms that are specific to graves disease
exopthalmous
peritibial edema
Graves disease pathogenesis
IgG antibodies (LATS, TSI) to TSH receptor / Type 2 Hypersens. reaction
MC indication for thyroidectomy in graves disease
suspicious nodule
Preop preparation thyroidectomy in graves disease
methimazole until euthyroid, β-blocker, Lugol’s solution for 14
days
preferred initial treatment for toxic multinodular goiter
surgery
Causes of Thyroiditis
- Hashimoto’s thyroiditis
- De Quervain’s thyroiditis (subacute granulomatous thyroiditis)
- Bacterial Thyroiditis
- Riedel’s fibrous struma
pathogenesis of hashimotos
both cellular and humoral immune mediated
cause of goiter in hashimotos
lack of organification of trapped iodide inside gland
Reidel’s fibrous struma thyroiditis
Woody, fibrous component that can involve adjacent strap muscles and carotid sheath
Disease commonly cause hypothyroidism and compressive syx
Types of thyroid cancer
- papillary
- follicular
- medullary
- hurthle cell thyroid ca
- anaplastic
features worrisome for thyroid malignancy
solid solitary cold nodule
Men
age >50
previous XRT
MEN2a MEN2b
voice change
MC type of thyroid ca
papillary
route of spread of papillary thyroid CA
lymphatic
prognosis of papillary thyroid CA based on
local invasion
histopathology of papillary CA
psammoma bodies
orphan Annie nuclei
Risk Factors for thyroid CA recurrence/metastasis
X-GAMES
– previous XRT, high
grade, age (< 20 or > 50), males, extrathyroidal disease, and size (> 1 cm)
worse prognosis of medullary thyroid CA
sporadic type
MEN2b
medullary thyroid CA tumor arises from which cells
parafollicular c cells
1st manifestation of MEN IIa and IIb
Diarrhea (due to calcitonin release from medullary thyroid CA
Age for prophylactic thyroidectomy and central node dissection is determined by
specific RET proto-oncogene codon mutation risk:
- Level A codon – before age 10 or earlier if lacks low-risk criteria
- Level B codon – before age 5 or later if low-risk criteria
- Level C codon – before age 5
- Level D codon – first year of life
(Low-risk criteria : normal calcitonin level, normal neck U/S, less aggressive MTC
family history)
iodine ablation therapy is only effective for which types of thyroid CA
papillary
follicular
how to monitor for recurrence after surgery
for papillary, follicular and medullary thyroid CA
papillary and follicular thyroglobulin level
Medullary : clacitonin level
Most important factor before initiating iodine ablation therapy
Make sure TSH is high to facilitate uptake of radioactive iodine
superior parathyroid are formed embryologically
4th pharyngeal pouch
inferior parathyroid are formed embryologically
3rd pharyngeal pouch
anatomy of superior parathyroid gland
found lateral to the RLN and superior to the inferior thyroid artery
anatomy of the inferior parathyroid gland
below inferior thyroid artery
medial to the RLN
MC location of ectopic parathyroid gland
tail of thymus
Osteitis fibrosa cystica
(brown tumors) – bone lesions from Ca
resorption; characteristic of hyperparathyroidism
labs in primary hyperparathyrodism
↑ PTH and ↑ Ca; ↓ PO4−; Cl− to PO4− ratio > 33; ↑ renal cAMP;
high urinary Ca (24-hour urine collection)
secondary hyperparathyroidism is seen in
renal failure patients
“Synchronous” tumors
Cases in which the second primary cancer is diagnosed within 6 months of the primary cancer
Metachronous tumors
Cases in which a second primary tumor is diagnosed (develops) more than 6 months after the primary cancer
sestamibi scan
Best for trying to pick up missing / ectopic parathyroid glands and for reops
Familial hypercalcemic hypocalciuria pathogensis
Caused by defect in PTH receptor in distal convoluted tubule of the
kidney that causes ↑ resorption of Ca
pseudohypoparathyroid
pathogenesis
defect in PTH receptor in the kidney, does not respond to PTH
Diarrhea is often the presenting symptom in what MEN syndromes
MEN2a
MEN2b
(due to increased calcitonin from medullary thyroid CA)
MEN1(MENIN gene)
(3Ps)
pituitary adenoma
parathyroid hyperplasia
pancreatic neuroendocrine tumor
MEN2a (RET proto-onco gene)
(2Ps,1M)
Parathyroid hyperplasia
Medullary thyroid CA
pheochromocytoma
MEN2b (RET proto-onco gene)
(1P,2Ms)
pheochromocytoma
Medullary thyroid CA
mucosal neuromas
marfinoid habitus
PTHrP secreted by which CA
squamous cell lung CA
Breast CA
Long thoracic nerve innervates
innervates serratus anterior; injury results in winged scapula
Lateral thoracic artery supply
supplies serratus anterior
Thoracodorsal nerve innervated
innervates latissimus dorsi; injury results in weak arm pull-ups
and adduction
Thoracodorsal artery supply
supplies latissimus dorsi
Medial pectoral nerve innervate
innervates pectoralis major and pectoralis minor
Lateral pectoral nerve innervates
pectoralis major only
Intercostobrachial nerve
lateral cutaneous branch of the 2nd intercostal nerve;
provides sensation to medial arm and axilla
breast arterial supply
Branches of internal thoracic (mammary) artery, intercostal arteries, thoracoacromial
artery, and lateral thoracic artery supply breast.
Mondor’s disease
superficial vein thrombophlebitis of breast
green/yellow/brown nipple discharge consistent with
fibrocystic disease of the breast
fibrocystic disease of the breast types
sclerosing adenosis, apocrine metaplasia, duct adenosis,
epithelial hyperplasia, ductal hyperplasia, and lobular hyperplasia
DCIS subtypes and the most aggressive of them all
comedo, papillary, cribriform, solid
comedo most aggressive
screening for breast cancer has decreased mortality by
25%
screening for breast CA age
- Average risk – annual mammogram starting at age 40
- High-risk – annual mammogram and MRI starting age 25-40
BRCA screening
- Yearly mammogram and breast MRI starting at age 25
- Yearly pelvic exam + U/S and CA-125 starting at age 25
Lung CA screening
yearly low dose CT chest
Indicated for patients 50–80 years old with > 20 pack-year smoking
history and are currently smoking or who have quit within last 15
years
MC solitary pulmonary nodule
Granuloma, hamartoma
persistant air leaks occurs after which type of thoracic surgeries
wedge
segmentectomy
lung cancer prognosis based on
nodal invlovement
types of lung cancer
Non–small cell carcinoma:
1.squamous cell ca
2.adenocarcinoma
Small cell carcinoma
Small cell CA paraneoplastic syndrome
ACTH and ADH
MC paraneoplastic syndrome ever
ACTH secreting small lung CA
unresectable lung disease according to stag
N2, N3 or M disease
how does lung hamartomas appear on
CT
calcification appear as popcorn lesion
Anterior mediastinal tumors
Ts
Thymoma
Thyroid CA or goiter
T-cell lymphoma
Teratoma
paraThyroid adenoma
posterior mediastinal tumors
Enteric cysts
neurogenic tumors
lymphoma
phases of empyema development
Exudative phase (1st week)
Fibro-proliferative phase (2nd week)
Organized phase (3rd–4th week)
Massive hemoptysis
> 600cc/24hr
spontaneous pneumothorax occurs more at which side
Right
surgery for pneumothorax
VATS apical blebectomy and mechanical pleurodesis
Catamenial pneumothorax
occurs in temporal relation to
menstruation
* Caused by endometrial implants in the visceral lung pleura
Ductus arteriosus
connection between descending aorta and left pulmonary artery (PA)
Ductus venosum
connection between portal vein and IVC; blood shunted away from liver
in utero
MC ASD type
ostium secundum
TOF components
- VSD
- Pulmonary stenosis
- RV hypertrophy
- Overriding aorta
medication used to close a PDA
indomethacin
Left main coronary branches
Left anterior descending
circumflex
Organisms responsible for endocarditis
staph aureus (50% of cases)
Stages of atherosclerosis
1st foam cells
2nd smooth muscle proliferation
3rd intimal disruption
carotid sheath contains
carotid artery, internal jugular vein, vagus nerve
MC site of carotid artery stenosis
bifurcation
first branch of internal carotid artery
ophthalmic artery
Gastrin produced by
G cells in stomach antrum
secretion of gastrin is stimulated by
amino acids, vagal input (acetylcholine),
calcium, ETOH, antral distention, pH > 3.0
secretion of gastrin is inhibited by
pH < 3.0, somatostatin, secretin, CCK
Target cells for gastrin
parietal cells and chief cells
effect of gastrin
↑ HCl, intrinsic factor, and pepsinogen secretion (gastrin
is the strongest stimulator for all)
somatostatin produced by
mainly produced by D (somatostatin) cells in stomach
antrum
secretion of somatostatin is stimulated by
acid in the duodenum
target cells of somatostatin
Many cells !!
it is the great INHIBITOR
effect of somatostatin
inhibits gastrin and HCl release (primary role); inhibits
release of insulin, glucagon, secretin, CCK, and motilin; ↓ pancreatic
and biliary output; slows gastric emptying
octreotide MOA
somatostatin analogue
CCK produced by
produced by I cells of duodenum
secretion of CCK stimulated by
amino acids and fatty acid chains
effect of CCK
gallbladder contraction, relaxation of sphincter of Oddi, ↑
pancreatic enzyme (exocrine) secretion (acinar cells)
Secretin is produced by
S cells of duodenum
secretion of secretin is stimulated by
fat, bile, pH < 4.0
secretion of secretin is inhibited by
pH > 4.0, gastrin
effect of secretin
↑ pancreatic HCO3− release (ductal cells), inhibits
gastrin release (this is reversed in patients with gastrinoma), and
inhibits HCl release
Vasoactive intestinal peptide produced by
pancreas and gut
secretion of VIP is stimulated by
fat, acetylcholine
effect of VIP hormone
increase water and electrolyte intestinal secretion
increase gut motility
glucagon is secreted by
alpha cells of the pancreas
glucagon release is stimulated by (starvation state)
↓ glucose, ↑ amino acids, acetylcholine
glucagon release is inhibited by
↑ glucose, ↑ insulin, somatostatin
effect of glucagon
glycogenolysis, gluconeogenesis, ↓ gastric acid secretion,
↓ gastrointestinal motility, relaxes sphincter of Oddi, ↓ pancreatic
secretion
insulin is secreted by
beta cells of the pancreas
secretion of insulin is stimulated by (fed state)
glucose, glucagons, CCK
secretion of insulin is inhibited by
somatostatin
Motilin is produced by
Mo cells in the upper small bowel
bowel recovery in order
- Small bowel 24 hours
- Stomach 48 hours
- Large bowel 3–5 days
Peristalsis phases of bowel
- I – resting
- II – accelerating
- III – peristalsis
- IV – decelerating
esophageal lining is made up of
non-keratinized squamous cell epithelium
muscle types of the esophagus
● Upper ⅓ esophagus – striated muscle
● Middle ⅓ and lower ⅓ esophagus – smooth muscle
arterial supply of the esophagus
● Thoracic esophagus – vessels directly off the aorta are the major blood supply
● Cervical esophagus – supplied by inferior thyroid artery
● Abdominal esophagus – supplied by left gastric and inferior phrenic arteries
venous drainage of the esophagus
hemi-azygous and azygous veins in the chest
left vagus travels
anteriorly
right vagus travels
posteriorly
length of esophagus
around 25 cm
length between the incisors and lower esophageal sphincter
around 40 cm
Anatomic areas of esophageal narrowing
- Cricopharyngeus muscle
- Compression by the left mainstem bronchus and aortic arch
- Diaphragm (near lower esophageal sphincter)
in pharyngeoesophageal disorders patients have more trouble with liquid or solid foods
liquid
plummer vinson syndrome
esophageal web, iron deficiency anemia
zenkers diverticulum is what type of diverticulum
False diverticulum
where is zenker’s diverticulum located
located posteriorly;
Occurs between superior pharyngeal constrictors and inferior cricopharyngeus
(Killian’s triangle)
causes of zenker’s diverticulum
failure of UES to relax leading to an increase in pressure
Traction esophageal diverticulum is true or false
True
epiphrenic diverticulum is true or false
false
pathogenesis of achalasia
Secondary to destruction of inhibitory neuronal ganglion cells in muscle wall (autoimmune
[#1], infectious, genetic)
difference between diffuse esophageal spasm and nutcracker esophagus
manometry for DES high amplitude NON-peristaltic movements
for nutcracker high amplitude peristaltic movements
scleroderma of the esophagus pathogenesis
● Fibrous replacement of esophageal smooth muscle
● Causes dysphagia and loss of LES tone with massive reflux and strictures
best test to diagnose GERD
24 hour pH probe
Most common cause of dysphagia following Nissen
wrap is too tight (generally resolves
on its own; give clears for 1st week; can dilate after 1 week)
types of hiatal hernia
● Type I – sliding hernia from dilation of hiatus (most common type)
● Type II – paraesophageal
● Type III – combined
● Type IV – sliding with entire stomach in the chest plus another organ
Needs barrett’s surveillance for lifetime even after Tx why ?
Barrett’s CA risk is not reversed with PPI or fundoplication.
risk factors for esophageal adenocarcinoma
GERD, obesity, Barrett’s
MC esophageal CA
adenocarcinoma
degrees of esophageal caustic injuries
- Primary burn – hyperemia
Secondary burn – ulcerations, exudates, and sloughing
Tertiary burn- Deep ulcer, charring, lumen narrowing
epidermis is subdivided into 5 layers
the
stratum basale (deepest), the stratum spinosum, the stratum
granulosum, the stratum lucidum and the stratum corneum
(superificial)
TIVA (total intravenous anaesthesia) advantage
reduce postoperative nausea and vomiting
ligasure can seal vessels up to
7mm in diameter
harmonic scalpel vs ligasure
harmonic scalpel uses ultrasound vibration
ligasure uses thermal energy
MC hepatic artery variant
right hepatic artery comes off SMA
line that divides liver into right and left lobe
Cantlie’s line
line that divides left lobe of the liver into medial and lateral
falciform ligament
portal triad and gallbladder are found in which liver segments
IV, V
kupffer cells
liver macrophages
Foramen of Winslow borders
- Anterior – portal triad
- Posterior – IVC
- Inferior – duodenum
- Superior – liver (caudate lobe)
Most primary and secondary liver tumors are supplied by
hepatic artery
usual energy source for liver
ketones
the only water-soluble vitamin stored in the liver
b12
primary bile acids (cholic and chenodeoxycholic) are made by
Bile salts are conjugated to taurine or glycine
deficiency in storage ability; high conjugated bilirubin
Rotor’s syndrome
deficiency in secretion ability; high conjugated bilirubin
Dubin–Johnson syndrome
urgent liver TXP listing if
King’s College criteria are met.
Budd–Chiari syndrome
hepatic vein occlusive disease (a cause of postsinusoidal portal HTN)
Child-Pugh Score depends on what parameters
Albumin
Bilirubin
INR
Encephalopathy
Ascites
MELD score depends on what parameter
uses INR, creatinine, and total bilirubin
splenic vein thrombosis can lead to what type of varices
Gastric varices
MC organism causing pyogenic abscess
Ecoli
preop ERCP done in liver hydatid cyst to
check for communication with the biliary system
Most common benign hepatic tumor
Hemangioma
sulfur colloid scan for hepatic mass
no uptake for adenoma because no kupffer cells
positive uptake for Focal nodular hyperplasia because there are kupffer cells
Metastasis:primary ratio of malignant liver tumors
20:1
MC malignant liver cancer
HCC
MC risk factor for HCC
hep B
tumor marker for HCC
AFP
calot triangle border
superior liver
medial common hep duct
lateral cystic duct
cystic artery is a branch off
right hepatic artery
gallbladder has no
submucosa
histopathology with cholecystitis
Rokitansky–Aschoff sinuses
bile leak after cholecystectomy u think off
cystic duct stump
CBD injury
ducts of luschka GB fossa
types of GB stones
cholesterol stones
black stones
brown stones
risk factors for black GB stone
hemolytic disorders, cirrhosis, chronic TPN
MC location and cause for brown biliary stones
CBD
caused by infection in biliary tree
Most sensitive test for cholecystitis
cholecystokinin cholescintigraphy
ACALCULOUS CHOLECYSTITIS risk factors
severe burns, prolonged TPN, trauma, or major surgery
PRIMARY SCLEROSING CHOLANGITIS is assocaited with
ulcerative colitis
Adenomyomatosis
thickened nodule of mucosa and muscle associated with
Rokitansky–Aschoff sinus
pancreatic blood supply
- Head – superior (off GDA) and inferior (off SMA) pancreaticoduodenal arteries (anterior
and posterior branches for each) - Body – great, inferior, and dorsal pancreatic arteries (all off splenic artery)
- Tail – splenic, gastroepiploic, and caudal pancreatic arteries
only pancreatic enzymes secreted in its active form
amylase
pathway of activation of pancreatic enzymes
trypsinogen is activated to trypsin by enterokinase secreted by the duodenum
Then trypsin activates EVERYTHING
major pancreatic duct that merges with CBD before entering duodenum
Duct of Wirsung
small accessory pancreatic duct that drains directly into duodenum
Duct of Santorini
(s for small duct)
Failed fusion of the pancreatic ducts is called
PANCREAS DIVISUM
MCC death in pancreatitis
sepsis
Ranson’s criteria
- On admission → age > 55, WBC > 16, glucose > 200, AST > 250, LDH > 350
- After 48 hours: Hct ↓ 10%, BUN ↑ of 5, Ca < 8, PaO2 < 60, base deficit > 4, fluid
sequestration > 6 L
best antibiotic to be given when needed for pancreatitis
imipenem
ARDS in pancreatitis is related to the release
phospholipases
Coagulopathy in pancreatitis is related to the release of
proteases
mnemonic for ON admission ranson criteria
WAGAL
wbc>16
age>55
glucose>200
AST>250
LDH>350
PANCREATIC PSEUDOCYSTS not associated with pancreatitis or known trauma u need to r/o
pancreatic CA
MC cause of chronic pancreatitis
Alcohol
number 1 risk factor for pancreatic adenocarcinoma
smoking
Pancreatic neuroendocrine tumors are divided into
non-functional (MC)
functional
MC functional PNET
insulinoma
symptoms of insulinoma
Whipple’s triad – fasting hypoglycemia (< 55), symptoms of hypoglycemia
, and relief with glucose
c-peptide in insulinoma is
increased
MC PNET in MEN-1
gastrinoma
MC location of gastrinoma
Gastrinoma triangle
gastrinoma triangle
common bile duct, neck of pancreas, third portion of the
duodenum
symptoms of glucagonoma
Symptoms (4 D’s): Diabetes, Dermatitis (rash – necrolytic migratory erythema),
Depression, DVT
symptoms of vipoma
watery diarrhea, hypokalemia, and achlorhydria (WDHA)
congenital lack of ligaments holding spleen in place is called
wandering spleen
ITP pathogenesis
anti-platelet antibodies (IgG to GpIIb/IIIa and Gp Ia/IIa) –
bind platelets; results in decreased platelets
THROMBOTIC THROMBOCYTOPENIC PURPURA
(TTP) pathogenesis
Due to ADAMTS13 defect (metalloproteinase that normally cleaves
vWF)
platelets go crazy and aggregates
Vaccines needed before splenectomy
Pneumococcus, Meningococcus,
H. influenzae
when to give vaccine in splenectomy
Give vaccines at least 14 days before elective surgery or 14 days after
emergency surgery
Most common congenital hemolytic anemia requiring splenectomy
spherocytosis
spherocytosis pathogenesis
Spectrin deficit (membrane protein, autosomal dominant) leads to
less deformable RBCs and splenic culling/sequestration
(hypersplenism).
which portions of the duodenum are retroperitoneal
2nd and 3rd
B12 and folate absorption occurn in
terminal ileum
iron absorption occurs in
duodenum
both jejunum and ileum are supplied by
SMA
Arcades and vasa recta difference between ileum and jejunum
for jejunum larger fewer arcades with longer vasa recta
jejunum and ileum arterial supply
SMA
non conjugated bile acids are absorbed by
passive diffusion
how much bowel u need to survive off TPN
Probably need at least 75 cm to survive off TPN; 50 cm with competent ileocecal valve
MCC of large bowel obstruction whether there history of surgery or no
colon Ca
failure of closure of the omphalomesenteric duct
MECKEL’S DIVERTICULUM
most common tissue found in Meckel’s
pancreatic tissue
when do u remove an incidentally found meckel’s diverticulum
gastric mucosa suspected (diverticulum feels
thick) or has a very narrow neck
which IBD is more associated with bloody diarrhea
UC
age of presentation for crohn’s disease
bimodal distribution
20–30s, 50–60s
extraintestinal manifestations of crohn’s disease
1.arthritis
2.uveitis
3.pyoderma gangrenosum
4.megaloblastic anemia
MC involved bowel segment in crohn’s
terminal ileum
histopathology for crohn’s disease
transmural inflammation
noncaseating granuloma
cobblestoning
creeping fat
skip lesions
narrow deep ulcers
why do crohn’s disease patients get calcium oxalate kidney stones
↓ oxalate binding to calcium secondary to ↑ intraluminal fat (fat binds Ca) →
oxalate then gets absorbed in colon → released in urine→hyperoxaluria
best for localizing carcinoid tumor not seen on CT scan
Octreotide scan
Most sensitive tumor marker for carcinoid tumor
chromogranin A
Peutz–Jeghers syndrome gene mutation
STK11 gene mutation; autosomal dominant
most common stomal infection
candida
parastomal hernias is mc associated with
colostomies
most common cause of stenosis of stoma
ischemia
FAP+osteomas called
Gardner’s syndrome
FAP+brain tumors
Turcot’s syndrome
Peutz–Jeghers syndrome
*benign hamartomas
*mucocutaneous pigmentation
*increase risk of breast Ca
GIST tumors arise from
intestinal calls of cajal
ckit mutation of GIST tumors allows which drug to work
Gleevec(imatinib)
MC location for GIST
gastric
Anal canal borders
extends from anorectal ring (puborectalis) to anal verge (squamous mucosa
and perianal skin junction)
Anal margin border
from squamous mucocutaneous junction to 5 cm out radially
Ascending and ⅔ of transverse colon blood supply
supplied by SMA (ileocolic, right and middle
colic arteries)
⅓ transverse, descending colon, sigmoid colon, and upper portion of the rectum blood supply
IMA (left colic, sigmoid branches, superior rectal artery)
Marginal artery
runs along colon margin, connecting SMA to IMA (provides
collateral flow)
Arc of Riolan
short direct collateral connection
between SMA and IMA
percentage of GI blood flow that supplies mucosa and submucosa
80%
Middle rectal artery is a branch of
internal iliac artery
inferior rectal artery is a branch of
internal pudendal artery (which is a branch of the internal iliac artery)
Superior rectal vein drain into
IMV and eventually the portal vein
Middle and inferior rectal veins drain into
internal iliac veins and eventually the IVC.
Watershed areas of large bowel
- Splenic flexure (Griffith’s point) – SMA and IMA junction
- Rectum (Sudeck’s point) – superior rectal and middle rectal junction
innervation of the external sphincter muscle
internal pudendal nerve
Stump pouchitis pathogenesis
lack of short chain fatty acids
Denonvilliers’ fascia (anterior)
rectovesicular and rectoprostatic fascia in men;
rectovaginal fascia in women
Waldeyer’s fascia (posterior)
rectosacral fascia
most common colon polyp
hyperplastic
risk factors for potentially cancerous polyps
> 2 cm, sessile, or villous
most important prognostic factor for colon CA
nodal status
FAMILIAL ADENOMATOUS POLYPOSIS (FAP) is associated with what gene mutation
APC
autosomal dominant
LYNCH SYNDROMES gene mutation
DNA mismatch repair gene
also called(hereditary nonpolyposis colon Ca)
autosomal dominant
Amsterdam criteria for Lynch syndrome
“3, 2, 1” → at least 3 first-degree relatives,
over 2 generations, 1 with cancer before age 50
histopathology of Ulcerative colitis
chronic inflammation involving the mucosa and submucosa
CRYPT ABSCSESS
complications of U.C
Toxic colitis
toxic megacolon
Toxic colitis criteria
> 6 bloody diarrhea/day
tachycardia
fever
leukocytosis
Toxic megacolon criteria
Toxic colitis criteria +
>6 cm large bowel
abdominal distention, pain and tenderness
Large bowel perforation with obstruction most likely to occur in
cecum
Spermatic cord structures rule of 3
Rule of 3s for the spermatic cord:
- 3 layers: External spermatic fascia, cremasteric fascia and internal spermatic fascia.
- 3 arteries: Artery to vas deferens, testicular artery and cremasteric artery.
- 3 nerves: Genital branch of genitofemoral nerve, ilioinguinal nerve and sympathetics.
- 3 other structures: Pampiniform plexus, vas deferens and testicular lymphatics.
name spermatic cord structures
testicular artery, pampiniform plexus, cremasteric
muscle, vas deferens, ilioinguinal nerve, genital branch of the genitofemoral nerve
Pantaloon hernia
direct and indirect components
most common early complication following hernia repair
Urinary retention
most common cause of hernia recurrence
Wound infection
Recurrence rate of hernia
2%
Most commonly injured nerve with open inguinal hernia repair
ilioinguinal nerve
Most commonly injured nerve with laparoscopic hernia repair
Lateral femoral cutaneous nerve
Femoral canal boundaries
Cooper’s ligament (pectineal, posterior), inguinal ligament
(anterior), femoral vein (lateral), and lacunar ligament (medial)
loss of cremasteric reflex; numbness on ipsilateral penis,
scrotum, and thigh after hernia surgery… nerve injured?
Ilioinguinal nerve injury
