Gastro - Online med ed/ healthpathways Flashcards
Acute gastroenteritis
Most common causes of gastro in NZ
- viral, bacterial
- What is the viral cause that causes flu like symptoms
-Norovirus and rotavirus
-Rotavirus - most common in kids and can cause cold symptoms
(rotator virus - rotates around body and causes flu symptoms)
-Bacterial - campylobacter
Acute gastroenteritis
When to do faceal testing for acute diarrhoea ?
When to request for giardia?
- diarrhoea is not resolving after 1 week.
- patient has been to an overseas location with poor water or sanitation.
- patient is a food handler, childcare or -healthcare worker, or is immunocompromised.
- patient is severely unwell, febrile, or has bloody diarrhoea
- test for giardia if rural or animal contact
- travllers - loperamide
Acute gastroenteritis
When to give Abx?
-what antibiotics for campylobacter
-management plan for general gastro-enteritis
- Dont give abx if afebrile, (self limiting)
- only give for campylobacter if severe, bloody diahorrhea and prolonged illness or febrile
- Azithromycin for campylobacter (think cAmpylobacter - for Azithromycin)
- replace fluids and electrolytes, infection control
- warn if serious pathogens
Acute gastroenteritis
why not give antibiotics to vertoxin or shiga toxin producing E.coli -
E.coli can cause haemolytic uraemic syndrome
Can make haemolytic uraemic syndrome far worse! so do not give
Haemolytic uraemic syndrome includes haemolytic anaemia, thrombocytopenia, and acute renal failure. Elderly patients with VTEC infections may suffer thrombotic thrombocytopenic purpura (TTP) which is similar to HUS, but with greater neurological involvement.
Acute gastroenteritis
How does invasive and enterotoxic mechanisms work?
what bacteria for each
- Enterotoxic - toxins produced from bacteria which turns cat from absopritive to secretory and get watery non bloody diahorrea, no fever, leukocytosis.
- c.diff
- virbio cholera
- E.coli
- Staph aureaus
- Giardia
- Invasive - invades into mucosa - causes bloody, WBCs, fever.
- shigella, salmonella, campylobacter, e.coli some forms
(think bloody SSC)
Acute gastroenteritis
What test to diagnose C.diff and what antibiotics
NAAT
metronidazole
Chronic diarrhoea
What are classic causes of diarrhoea to rule out and how?
Medications
Laxatives
Lactose (lactose test)
Stool culture (infection)
Causes of secretory diarrhoea
Anything that causes the gut from absorptive to secetory- can be caused by enterotoxins, c.diff and hormone levels from some cancers
Normal osmotic gap, no fat, no blood
VIPoma Gastrinoma Carcinoid C.diff (other infective causes all but the SSC (shigella, salmonella, campylobacter))
-check hormone levels, colonoscopy, stool culture (infections)
Osmotic
- something being in the lumen which draws water out of body and into lumen
- Usually due to a product of malabsorption (lactose, glucose, fat, protein)
- no blood, mucous, but will have osmolarity gap
- will have fecal fat
- nil by mouth - can make this better so try
- endoscopy w biopsy, secretin test, specific test
- coeliac, lactose deficiencey, insufficieny malabsorption
Gastrinoma
VIPoma
Carcinoid
Gastrinoma - persistant ulers w diarrhea - zollinger ellison or gastrin producing tumour.
1. measure serum gastrin, CT scan
VIPoma - high serum VIP
Carcinoid - small intestine, metastatsizes to lvier then can cause problems
-right heart failure, flushing, diarrhea. Urinary 5-HIAAA to confirm
Extra-intestinal manifestations of IBD
Skin, e.g. erythema nodosum, pyoderma gangrenosum Arthritis Eye, e.g. episcleritis, iritis Mouth ulcers Night sweats Primary sclerosing cholangitis
Investigations for IBD first presentation
Initial investigations: FBC, CRP, LFTs, electrolytes, coeliac markers, faecal culture (including ova and parasites if appropriate) and Clostridium difficile (C diff) toxin. faecal calprotectin (good to rule out IBD)
- anaemia, leukocytosis, thrombocytosis, increased CRP - IBD
- colonoscopy
Initial Medications for IBD
and long term medications
- start on 5-ASA (mesalazine, sulfisalazine)
- steroids
- wait for gastro review
5-ASA Steroids (flare) Immunomodulators - Thipurines - azathoprine, mercaptopruine Methotrexate Biologics - infliximab, adalimumab (TNF blocekrs)
Management for IBD
What can steroids do to bone?
Smoking cessation Immunosupression Nutrition Bone density (steroids can reduce this) Contraception (depoprovera can also reduce bone density ) Pregnancy (methotrexate NO, steroids - maybe) Extra-intestinal manifestations Regular colon cancer screening
UC and Crones - extra
UC - PSC, erythema nodosum, apthlous ulcers, increased risk of colon cancer
Crones - transmural - goes all way to serosa
UC - just to submucosa or mucosa
Crones - weight loss, fistulas, nutritional deficiencies, extra manifestations are not as much as UC
IBD flare management
red flags - rule out toxic megacolon, perforation, bowel obstruction, abscess
(redflags Fever, tachycardia, hypotension, or abdominal pain)
more than 6 bloody bowel motions + CRP high, HB low, heart rate or temp off
- First - faecal culture and c.diff
- FBC, CRP, LFTs, ELectrolytes
-Start prednisone if needed, increase 5-asa for UC
Screening for Colon cancer
60-75 year olds - every two years
- Faecal immunochemical test via mail (detects blood in stool)
- if negative then next two eyars
- If positive - colonocopy (CT if unfit for this)
Mildy increased risk - normal FIT, if symptosm - check out, can have private (fam hist one relative >55)
Mod - relative <55 years, two relative w CRC diagnosed any cage
-Colonoscopy every 5 years from age >50. or form 10 year before the earliset age whcih bowel cancers was foudn in fam
High risk - Fam hist familial adenomatous poplypsoso, or heriditary non-popyposis colorectal cancer. Strong family history of bowel cancer.
-refer to NZ familialr GI cancer service
Main symptoms of colorectal cancer
- Iron deficicncey anaemia (male or post menopausall female)
- alternating bowel habits
- change in stool calibre
Colonoscopy, CT (metastisis)
Types of polyps
adenomatous polyps - removed and analysed
sessile and villous - increased risk of malignant transformation
-peducnculated, tubular polyps - low risk
How to stage colon cancer
-TNM - tumour - how far through walls (1. submucosa, 2. muscularis, 3. subserosa, 4.a surface of visceral peritoneum. 4.b attached to other structures.
N- nodes
M - 1. a - other part of body b. more than 1 other part. c. peritoneal surface.
Differences in investigation/management for rectal and colon cancer
Double check this!!!
rectal - chemo, radiation, surgery
Colon - chemo, surgery
Diverticulosis spasm (symptomatic diverticulitis)
- Old lady, LLQ post prandial pain, relieve with BM (similar to IBS)
- Treat with high fiber diet
Diverticular bleed
- Bright red blood from rectum, no pain,
- First - rule out upper GI bleed (NG tube, gastroscopy)
- Colonoscopy no bleed, tagged RBC slow, angiogram - if brisk bleed!
- more common right than left
-treat - embolization, cautery, resection
Diverticulitis + perforation
complicated w abscess, fistula, bowel obstruction or perforation
- elderly appendicitis presentation
- fever, leukocytosis, rebound tenderness
Inv - FBC, ferritin, creatinine, electrolytes, urinalysis, LFTs, HCG, CRP
- Xray - free air or ileus (rule out bowel obstruction or perforation)
- CT scan
- No colonoscopy until 2-6 weeks after
-anagesia +
Mild - liquid diet, Oral abx
Severe - NBM, IV abx, IVF,
Abscess - NBM, IV abx, IVF, drainage
Antibitoics - Trimethorpim + sulfamethoxale and metronidazole
or Augmentin
