Appendicitis/ Bowel Disease Flashcards
most common acute abdominal condition requiring surgery.
Acute appendicitis
Acute appendicitis can occur at any age but is most common in young people aged 10-20 years.
true
Acute appendicitis patients often report the pain being worse on
worse on coughing or going over speed bumps. Children typically can’t hop on the right leg due to the pain.
Acute appendicitis Abdominal pain is seen where?
peri-umbilical abdominal pain
radiating to the right iliac fossa (RIF)
Acute appendicitis mild pyrexia is common
true
Acute appendicitis o/e
generalised peritonitis - rebound and percussion tenderness, guarding and rigidity
psoas sign: pain on extending hip if retrocaecal appendix
Rovsing’s sign (palpation in the LIF causes pain in the RIF) is now thought to be of limited value
pelvic abscess o/e
digital rectal examination may reveal boggy sensation if pelvic abscess is present, or even right-sided tenderness with a pelvic appendix
Acute appendicitis diagnosis?
Bloods
neutrophil-predominant leucocytosis is seen in 80-90%
Acute appendicitis diagnosis?
Urinalysis
urinalysis may show mild leucocytosis but no nitrites
exclude pregnancy in women, renal colic and urinary tract infection
there are no definite rules on the use of imaging and its use is often determined by the patient’s gender, age, body habitus and the likelihood of appendicitis
true
imaging and acute appendicitis
Clincial diagnosis - thin males
US - females query pelvic pathology
Mx acute appencititis
laparoscopic appendicectomy
prophylactic intravenous antibiotics
patients with perforated appendicitis (typical around 15-20%) require
copious abdominal lavage.
appendicitis - be wary in the older patients who may have either an underlying caecal malignancy or perforated sigmoid diverticular disease.
true
Angiodysplasia is
vascular deformity of the gastrointestinal tract which predisposes to bleeding and iron deficiency anaemia.
Angiodysplasia is assoc with
aortic stenosis
Angiodysplasia is generally seen in
elderly patients
Angiodysplasia diagnosis
colonoscopy
mesenteric angiography if acutely bleeding
Angiodysplasia mx
endoscopic cautery or argon plasma coagulation
antifibrinolytics e.g. Tranexamic acid
oestrogens may also be used
Clostridium difficile is a
Gram positive rod
Clostridium difficile produces exo/endotoxin
exotoxin
Clostridium difficile roduces an exotoxin which causes intestinal damage leading to a syndrome called
pseudomembranous colitis
Clostridium difficile develops when the normal gut flora are suppressed by broad-spectrum antibiotics
which abs?
Clindamycin
cephalosporins
Leading cause of Clostridium difficile.
Second and third generation cephalosporins
C diff Other than antibiotics, risk factors include:
PPIs
C diff Features
diarrhoea
abdominal pain
a raised white blood cell count (WCC) is characteristic
if severe toxic megacolon may develop
C diff
severity scale?
Mild: Normal WCC
Moderate: ↑ WCC ( < 15 x 109/L)
Typically 3-5 loose stools per day
Severe: ↑ WCC ( > 15 x 109/L)
or an acutely ↑ creatinine (> 50% above baseline)
or a temperature > 38.5°C
or evidence of severe colitis(abdominal or radiological signs)
life-threatening: Hypotension
Partial or complete ileus
Toxic megacolon, or CT evidence of severe disease
Clostridium difficile Diagnosis?
is made by detecting Clostridium difficile toxin (CDT) in the stool
Clostridium difficile antigen positivity only shows exposure to the bacteria, rather than current infection
Management C Diff?
first-line therapy is oral metronidazole for 10-14 days
if severe or not responding to metronidazole then oral vancomycin may be used
patients who are not responding , particularly those with multiple co-morbidities c diff?
fidaxomicin
C Diff for life-threatening infections?
combination of oral vancomycin and intravenous metronidazole should be used
It is currently thought there are three types of colon cancer:
sporadic (95%)
hereditary non-polyposis colorectal carcinoma (HNPCC, 5%)
familial adenomatous polyposis (FAP, <1%
Most common form of inherited colon cancer.
HNPCC
HNPCC, an autosomal dominant condition
True
Around 90% of patients develop cancers, often of the proximal colon
true
Colorectal Ca most common genes involved
MSH2 (60% of cases)
MLH1 (30%)
Patients with HNPCC are also at a higher risk of other cancers, with what cancer being the next most common association, after colon cancer.
endometrial
Colorectal ca
The Amsterdam criteria are sometimes used to aid diagnosis:
at least 3 family members with colon cancer
the cases span at least two generations
at least one case diagnosed before the age of 50 years
what is a rare autosomal dominant condition which leads to the formation of hundreds of polyps by the age of 30-40 years.
FAP
FAP is what?
mutation in a tumour suppressor gene called adenomatous polyposis coli gene (APC), located on chromosome 5.
A variant of FAP called Gardner’s syndrome can also feature
osteomas of the skull and mandible, retinal pigmentation, thyroid carcinoma and epidermoid cysts on the skin
Diverticulosis is an extremely common disorder characterised by multiple outpouchings of the bowel wall, most commonly in
sigmoid colon.
Risk factors diverticulosis
increasing age
low-fibre diet
Diverticulosis sx
painful diverticular disease: altered bowel habit, colicky left sided abdominal pain.
diverticulosis high fibre diet is usually recommended to minimise symptoms
true
One of the diverticular become infected. The classical presentation is:
left iliac fossa pain and tenderness
anorexia, nausea and vomiting
diarrhoea
features of infection (pyrexia, raised WBC and CRP)
Diverticulitis mx
mild attacks can be treated with oral antibiotics
more significant episodes are managed in hospital. Patients are made nil by mouth, intravenous fluids and intravenous antibiotics (typical a cephalosporin + metronidazole) are given
Complications of diverticulitis include:
abscess formation
peritonitis
obstruction
perforation
Ischaemia to the lower gastrointestinal tract can result in a variety of clinical conditions. Whilst there is no standard classification it can be useful to separate cases into 3 main conditions
acute mesenteric ischaemia
chronic mesenteric ischaemia
ischaemic colitis
bowel ischaemia Common predisposing factors
increasing age
atrial fibrillation - particularly for mesenteric ischaemia
other causes of emboli: endocarditis, malignancy
cardiovascular disease risk factors: smoking, hypertension, diabetes
cocaine: ischaemic colitis is sometimes seen in young patients following cocaine use
bowel ischaemia bloods typically show
elevated white blood cell count associated with a lactic acidosis
bowel ischaemia diagnosis
CT
Ischaemic colitis describes
acute but transient compromise in the blood flow to the large bowel.
Ischaemic colitis more likely to occur in
‘watershed’ areas such as the splenic flexure that are located at the borders of the territory supplied by the superior and inferior mesenteric arteries.
Ischaemic colitis Investigations
‘thumbprinting’ may be seen on abdominal x-ray due to mucosal oedema/haemorrhage
Metabolic alkalosis - Causes
vomiting / aspiration (e.g. peptic ulcer leading to pyloric stenos, nasogastric suction) diuretics liquorice, carbenoxolone hypokalaemia primary hyperaldosteronism Cushing's syndrome Bartter's syndrome
Molecular biology techniques
Southern blotting Detects DNA
Northern blotting Detects RNA
SNOW (South - NOrth - West)
DROP (DNA - RNA - Protein)
Molecular biology techniques Western blotting detects?
Detects proteins
Uses gel electrophoresis to separate native proteins by 3-D structure
Examples include the confirmatory HIV test
Molecular biology techniques - what is ELISA
a type of biochemical assay used to detect antigens and antibodies
a colour changing enzyme is attached to the antibody if looking for an antigen and to an antigen if looking for an antibody
the sample therefore changes colour if the antigen or antibody is detected
an example includes the initial HIV test
Peutz-Jeghers syndrome is
autosomal dominant condition characterised by numerous hamartomatous polyps in the gastrointestinal tract
Peutz-Jeghers is assoc with freckles
true
pigmented freckles on the lips, face, palms and soles
PJS he polyps themselves don’t have malignant potential, around 50% of patients will have died from another gastrointestinal tract cancer by the age of 60 years.
true
PJS responsible gene
LKB1 or STK11
Peutz-Jeghers syndrome mx
conservative unless complications develop
Small bowel bacterial overgrowth syndrome (SBBOS) is
disorder characterised by excessive amounts of bacteria in the small bowel resulting in gastrointestinal symptoms.
SBBOS risk factors
neonates with congenital gastrointestinal abnormalities
scleroderma
diabetes mellitus
SBBOS many of the features overlap with irritable bowel syndrome
true
SBBOS diagnosis
hydrogen breath test
clinicians may sometimes give a course of antibiotics as a diagnostic trial
SBBOS mx
correction of underlying disorder
antibiotic therapy: rifaximin
Spontaneous bacterial peritonitis
Diagnosis
paracentesis: neutrophil count > 250 cells/ul
Spontaneous bacterial peritonitis most common organism found on ascitic fluid culture is
E. coli
Spontaneous bacterial peritonitis
Antibiotic prophylaxis should be given to patients with ascites if:
patients who have had an episode of SBP
patients with fluid protein <15 g/l and
either Child-Pugh score of at least 9 or hepatorenal syndrome
Spontaneous bacterial peritonitis which abs
oral ciprofloxacin or norfloxacin
Villous adenomas are
colonic polyps with the potential for malignant transformation. They characteristically secrete large amounts of mucous, potentially resulting in electrolyte disturbances.
Villous adenomas are mostly asymptomatic
true
Villous Adenoma - The vast majority are asymptomatic. Possible features:
non-specific lower gastrointestinal symptoms
secretory diarrhoea may occur
microcytic anaemia
hypokalaemia
Whipple’s disease is
are multi-system disorder caused by Tropheryma whippelii infection
Whipple’s disease is more common in?
more common in those who are HLA-B27 positive and in middle-aged men.
Whipples disease symptoms
malabsorption: diarrhoea, weight loss
large-joint arthralgia
lymphadenopathy
skin: hyperpigmentation and photosensitivity
pleurisy, pericarditis
neurological symptoms (rare): ophthalmoplegia, dementia, seizures, ataxia, myoclonus
Whipple’s disease diagnosis?
jejunal biopsy shows deposition of macrophages containing Periodic acid-Schiff (PAS) granules
Whipple’s disease mx guidelines vary
true
guidelines vary: oral co-trimoxazole for a year is thought to have the lowest relapse rate, sometimes preceded by a course of IV penicillin
