o Flashcards
cancer colorectal types
The diagnosis is Familial Adenomatous Polyposis. FAP is an autosomal dominant condition that leads to the formation of hundreds of polyps in the bowel by age 30-40. The gene involved in Familial Adenomatous Polyposis is the APC gene found on chromosome 5.
MLH1 is incorrect. This gene is involved in HNPCC (Lynch syndrome) which is the most common hereditary cause of colorectal cancer. However, multiple polyps are rarely a feature of HNPCC.
MSH2 is incorrect. This gene is also involved in HNPCC (Lynch syndrome). As mentioned above, the colonoscopy findings are more consistent with familial adenomatous polyposis.
most common form of inherited colorectal cancer
HNPCC
HNPCC (Lynch syndrome), an autosomal dominant condition, is the most common form of inherited colon cancer. Around 90% of patients develop cancers, often of the proximal colon, which are usually poorly differentiated and highly aggressive. Currently seven mutations have been identified, which affect genes involved in DNA mismatch repair leading to microsatellite instability. The most common genes involved are:
MSH2 (60% of cases)
MLH1 (30%)
hundred of polyps what gene
APC - chromosome 5
coeliac disease cause malabsorption due to
Villous atrophy is the correct answer. Villous atrophy occurs in coeliac disease due to an autoimmune response against gluten which leads to inflammation and destruction of intestinal villi. Histological features of coeliac disease include villous atrophy, crypt hyperplasia and raised intraepithelial lymphocytes.
most common complication of ERCP
Acute pancreatitis
high urea associated with upper or lower go bleed
upper
what drugs can cause drug-induced vitamin B12 deficiency
PPI and metformin
where are femoral and inguinal hernias in comparison to each other
The femoral canal lies just below the inguinal ligament and lateral to the pubic tubercle. Consequently, a femoral hernia will pass below and lateral to the pubic tubercle, whereas an inguinal hernia will be seen above and medial to it. The key landmark for the femoral canal is the femoral vein.
A direct inguinal hernia is caused by a weakness in the posterior wall of the inguinal canal. The abdominal contents (usually just fatty tissue, sometimes with bowel) are forced through this defect and enter the inguinal canal. This means that the contents emerge in the canal medial to the deep ring (as shown).
An indirect inguinal hernia, however, does not pierce the posterior wall. The abdominal contents pass through the deep inguinal ring, passing through the inguinal canal and exiting via the superficial ring.
The principle of this is that if you can place your finger over the deep inguinal ring (just above the mid-point of the inguinal ligament), then you can control an indirect inguinal hernia which has been reduced. If when you press the deep ring, the hernia still protrudes, then the hernia is emerging via a defect in the posterior wall medial to this point and is, therefore, a direct hernia
The location of the neck of the hernia (superior and medial to the pubic tubercle) suggest this is an inguinal hernia as opposed to a femoral hernia which would be inferior and lateral to the pubic tubercle.
A direct inguinal hernia enters the inguinal canal by passing though the posterior wall of the inguinal canal rather than the deep inguinal ring therefore would reappear despite pressure on the deep inguinal ring.
An indirect inguinal hernia enters the inguinal canal through the deep inguinal ring and exits the inguinal canal at the superficial inguinal ring so would not be able to reappear if the deep inguinal ring was occluded.
Bile acid malabsorption can lead to steatorrhoea and Vitamin A, D, E, K malabsorption
test of choice for this and treatment
the test of choice is SeHCAT
bile acid sequestrants e.g. cholestyramine
The hepatobiliary triangle is bordered by the common hepatic duct (medially), the cystic duct (inferiorly) and the inferior edge of the liver (superiorly). This anatomical space is of clinical importance during laparoscopic cholecystectomy for the safe ligation and division of the
cystic duct and cystic artery.
You decide to take an arterial blood gas from the femoral artery. Where should the needle be inserted to gain the sample?
The mid inguinal point is midway between the anterior superior iliac spine and the symphysis pubis
apocrine gland
sweat gland
desmoid tumours associated with what tumour suppressor gene
APC
what score assesses the severity of acute pancreatitis
The Modified Glasgow criteria is used to assess the severity of acute pancreatitis.
A 3-day old neonate with Down’s syndrome has been copiously vomiting while on the ward. The mother had a full term pregnancy with no complications. He has not passed his first bowel motion and the parents are becoming more anxious.
On examination, the abdomen is slightly distended.
What area does the pathology lie within the colon?
and what disease e
The neonate has Hirschsprung disease where there is an absence of ganglion cells in the myenteric nerve plexus (also known as Auerbach’s plexus) resulting in a lack of peristalsis. Features of this condition include nausea and vomiting, bloating, delay in the passage of meconium (first bowel motion). Males and children with Down’s syndrome have a higher risk of this condition.
Hirschsprung’s disease is caused by parasympathetic neuroblasts failing to migrate from the neural crest to the distal colon → developmental failure of the parasympathetic Auerbach and Meissner plexuses
Associations
3 times more common in males
Down’s syndrome
Possible presentations
neonatal period e.g. failure or delay to pass meconium
older children: constipation, abdominal distension
Investigations
abdominal x-ray
rectal biopsy: gold standard for diagnosis
Management
initially: rectal washouts/bowel irrigation
definitive management: surgery to affected segment of the colon
what artery supplies the lesser and greater curvatures of the stomach
Left gastric artery supplies the proximal lesser curvature of the stomach.
Right gastric artery supplies the distal lesser curvature of the stomach.
Left gastroepiploic artery supplies the proximal greater curvature of the stomach.
Right gastroepiploic artery supplies the distal greater curvature o the stomach.
Short gastric arteries supply the proximal greater curvature of the stomach above the splenic artery.
repair of inguinal hernia
TEP repair
what gene mutation is associated with pancreatic cancer
The KRAS gene mutation is associated with pancreatic cancer
what is a biomarker for colon cancer
CEA is a tumour biomarker for colorectal cancer, rather than a genetic mutation.
most common type of pancreatic cancer
adenocarcinoma
tumour suppressor gene linked to pancreatic cancer
BRCA2
sx of pancreatic cancer
classically painless jaundice
pale stools, dark urine, and pruritus
cholestatic liver function tests
Courvoisier’s law states that in the presence of painless obstructive jaundice, a palpable gallbladder is unlikely to be due to gallstones
however, patients typically present in a non-specific way with anorexia, weight loss, epigastric pain
loss of exocrine function (e.g. steatorrhoea)
loss of endocrine function (e.g. diabetes mellitus)
atypical back pain is often seen
migratory thrombophlebitis (Trousseau sign) is more common than with other cancers
ix fro pancreatic cancer
what sign may be present
US
high-resolution CT scanning is the investigation of choice if the diagnosis is suspected
imaging may demonstrate the ‘double duct’ sign - the presence of simultaneous dilatation of the common bile and pancreatic ducts
SAAG means what in the abdomen and what condition
Ascites: a high SAAG gradient (> 11g/L) indicates portal hypertension
Nephrotic syndrome would present with oedema but the vignette will often give you proteinuria and hypoalbuminaemia as well (which is the classic triad in nephrotic syndrome questions). Additionally, the raised liver enzymes and macrocytic anaemia are more in line with liver pathology.
gilbert syndrome pattern of inheritance
autosomal recessive
Right heart failure is associated with a what kind of liver
firm, smooth, tender and pulsatile liver edge
thoracic duct crosses diaphragm
T10
behind oepsahgus
no polyp cancer and polyp cancer what genes
This patient is presenting with hereditary non-polyposis colorectal cancer (HNPCC), which is caused by a mutation in the DNA mismatch repair genes MSH2/MLH1. HNPCC causes a very high likelihood of developing colorectal cancer before and is inherited in an autosomal dominant fashion.
Mutations in APC gene are a cause of familial adenomatous polyposis (FAP). This typically causes a very high number of polyps to develop in the intestine. These polyps are generally benign, but due to their high number, there is an increased risk of a malignant change occurring.
medial to inf epigastric artery what hernia
direct
lateral is indirect - this one goes through deep ring and superficial ring to scortum - most common
hesselbach triangle
inguinal ligament inf
inferior epigastric lat
rectus abdominus medially
what hernia pushes through this
direct hernia - weak floor inguinal canal - only sup ring
SAD PUCKER
A good method for remembering the retroperitoneal structures is: SAD PUCKER
Suprarenal (adrenal) glands
Aorta/inferior vena cava
Duodenum (2nd and 3rd parts)
Pancreas (except tail) Ureters Colon (ascending and descending) Kidneys (o)Esophagus Rectum
