(gastro) gastrointestinal disorders & infections Flashcards
what do elevated CRP and WCC indicate?
indicate an infective/inflammatory process
what does an elevated creatinine indicate?
usually (acute) kidney injury
what are the main differential diagnoses for infectious diarrhoea?
Clostridium difficile
Klebsiella oxytoca
Clostridium perfringens
Salmonella spp
what are the main differential diagnoses for non-infectious diarrhoea?
antibiotics side effect
post-infectious irritable bowel syndrome
haemorrhoids
inflammatory bowel disease
microscopic colitis
ischaemic colitis
coeliac disease
for a patient that presents with the following, what is the most appropriate next investigation?
- day 4 post-surgery, on antibiotics, with new-onset diarrhoea, generalised tenderness
- investigations show:
↑ed WCC & CRP indicating an inflammatory/infective process + has an acute kidney injury indicating dehydration
a) stool sample for C.diff toxin
b) stool culture
c) imaging (AXR)
d) endoscopy
e) all of the above
a, b and c
a) stool sample for C.diff toxin = to investigate most likely differential
b) stool culture = to rule out other possible causes
c) imaging (AXR) = to look for dilated bowel loops or subdiaphragmatic air
d) UNLIKELY - as if the diagnosis is pretty clear form the above investigations, will not do an invasive diagnostic test after
why is an endoscopy not really used to investigate differentials unless specifically required?
as if the diagnosis is pretty clear form the above investigations, will not do an invasive diagnostic test to confirm
(= endoscopy increases perforation risk significantly)
describe the following scan
normal abdominal X-ray
how is C. diff infection managed?
infection control
- move patient into side rooms, isolate
discontinue inciting antibiotic agents
- stop abx causing the problem and start on oral/IV vancomycin or metronidazole
control dehydration
- fluid rehydration, nutrition
what are dry oral mucosa and skin turgor indicative of?
dehydration
how is C. diff classified in terms of severity?
non-severe infection
= WCC < 15, creatinine < 150
severe infection
= WCC > 15, creatinine > 150
fulminant colitis
= severe infection + either hypotension or shock/ileus/signs of toxic megacolon
what are the indications for non-severe C. diff infection?
WCC < 15, creatinine < 150
what are the indications for severe C. diff infection?
WCC > 15, creatinine > 150
what are the indications for fulminant colitis?
severe infection AND either hypotension/shock/ileus/signs of toxic megacolon
what is fulminant colitis?
= C.diff colitis with significant systemic toxic effects and shock
how is non-severe C. diff infection managed?
antibiotic therapy with oral vancomycin or fidaxomicin or metronidazole
role of faecal microbiota transplantation (FMT)
how is severe C. diff and fulminant colitis infection managed?
antibiotic therapy
supportive care
close monitoring
early surgical consultation (in case symptoms worsen and require immediate surgical intervention)
what does the following AXR indicate and why?
a) toxic megacolon
b) small bowel obstruction
c) large bowel obstruction
d) ileus
dilated small bowel loops and dilated large bowel
= approx 8-9cm wide + looks like transverse colon
so toxic megacolon (!!)
what is toxic megacolon?
swelling and inflammation spread into the deeper layers of your colon
colon stops working and widens and can even rupture in severe cases
what is ileus?
lack of movement somewhere in the intestines that leads to a buildup and potential blockage of food material
= can lead to obstruction and can occur as a side effect of surgery
what is the first-line treatment for fulminant colitis with toxic megacolon?
medical therapy with antibiotics and supportive management (rehydration)
usually transfer to ITU for invasive monitoring (fluid resuscitation & ionotropic support)
what is fluid resuscitation?
replenishing bodily fluid lost through sweating, bleeding, fluid shifts or other pathologic processes
when is a patient fluid resuscitated?
when they have lost significant amounts of fluid that needs to be replenished
(e.g. when patient is NBM, severe diarrhoea, sever vomiting, hypovolaemia due to blood loss)
what is ionotropic support?
inotropic support to stabilise circulation and to optimise oxygen supply
(negatively inotropic agents = weaken force of muscular contractions; positively inotropic agents = increase strength of muscular contraction)
when is ionotropic support given?
acute conditions where there is low cardiac output (e.g. congestive heart failure, MI, cardiogenic shock post-surgery)
= to prevent tissue hypoperfusion
