IBS Flashcards
What is IBS?
Is a functional gastrointestinal disorder involving disturbance in bowel function affecting the sensorimotor function of the gut.
A syndrome with a diagnosis made of cluster of x in the absence of structural abnormalities.
What is fecal calproctectin?
A non- invasive market of mucosal inflammation.
Treatment decision made on disease is based on what?
Severity and and location rather than strictly by diagnosis.
Diagnosis for IBD are..
Patient history Various tests including blood tests. Stool tests (esp fecal calprotectin), Endoscopy Biopsies Imaging studies
In suspected IBD tests should aimed at what?
Differentiating IBD from infectious gastrointeritis and coeliac dse.
Ix also helps in defining dse activity and severity.
Lab test Ix should include blood and stool to rule out what?
Other causes of diarrhea and inflammation
Blood tests are not specific for IBD but may be done to detect and evaluate what?
Severity of inflammation
Anemia
Vitamin or mineral deficiency associated with IBD
FBC can reveal what?
Anemia - low mean corpuscular volume (MCV)
High MCV suggesting B12 or folate deficiency or seen in patients on immunomodulators such as thioprines
Normal MCV with high red cell distribution width (RDW) indicating iron and folate def or folate and vit B 12
WCC elevation - evidence of inflammation
Low Albumin
Inflammation and malnutrition
Raise creatinine and urea
Evidence of dehydration
Electrolyte disturbances
Low magnesium, selenium, potassium, zinc
Rrlated to poor diet and long standing diarrhea
Low ferritin
Iron def < 100 microgram
Elevated serum ferritin can be a marker of inflammationesp in liver rrlated inflammation
Non-celiac features includes
Fistulas
Perianal dse
Bloody stool
Fecal calprotectin is widely used neutrophil derived protien biomarker in Australia.
Highly sensitive, non invasive marker of intestinal inflammation therefore is useful in the ff settings.
What are they?
Differentiating people with or without lower gut inflammation bet people with IBS and IBD
Monitoring people on therapy to check disease activity or response to tx
Assess mucosal heal is achieved where colonoscopy is not practicable due to cost, access, patient comorbidities and Pt’s refusal
Stool testing with suspected IBD is valuable tool to determine enteric infections such as what?
Clostridium difficile (common in elderly, immunocompromised and on antibiotic therapy)
Tx of IBD w/ immunosuppression without addressing infectious pathogens can be dangerous
FOBT testing can reveal what?
Traces of blood that cannot be seen with the naked eye
A screening tests for colorectal ca and should not be used as a diagnosis for IBD
Other stool culture for patients who travelled abroad to check infectious diseases
Endoscopy and colonoscopy with histology and radiology are used for what?
Diagnosis of IBD to assess it’s extent and severity
To prevent young Pt’s from unnecessary exposure to radiation by using MRI over CT if possible
First line procedure to establish diagnosis and extent of IBD
Colonoscopy with ileoscopy with multiple biopsy specimens
Endoscopy is used for
Visual exam of the the entire lining of large intestine
Examine ulcers, inflammation, bleeding, stenosis
Multiple biopsies from the colon to TI
Lack of response to tx
Assess CMV infections - testing on biopsies, PCR. Pt’s on chronic use of immunosuppressants or w/ C diff infection appearances suggests pseudomembranes
Colonoscopy for dysplasia surveillance
Upper GI endoscopy is ised for upper GI sx such as nausea, vomitting, epi pain
Capsule endoscopy is used for what?
To assess presence, extent and severity of small bowel involvement in Crohn’s dse
Stricturing Crohn’s dse is a contraindication
Plain abdo xray is used for?
Wether colitis is present and its extent in some cases of UC
Exclude toxic megacolon with acute severe colitis
Give impression of mass on RIF or show dilatation or obstructions on CD
Barium double contrast enema
Is rarely used and is replaced by colonoscopy.
When is it helphlful?
In rare circumstances when colonoscopy is incomplete or to delineate the lenght of a colonic stricture
When is USS and MRI used?
To determine the extent and severity of the disease to assess for perforating complications
Intestinal USS permits a real time assessment of disease activity including what are they??
Quantifying inflammatory burden that assist in determining the inflammatory and fibrotic components of a stricture
Determine sx are due to active diseases or due to functional issues such as faecal loading.
It is non- invasive, don in an unprepped bowel
Relatively safe
Dual emission Xray absorptiometry
To assess bone mineral density
CXR
Exclude TB
Look for free air under fiaphragm in case of perforation
Referral to specialist should not be delayed for high risk patients due to poor outcome and prevent avoidable bowel resection
Who are those people at risk?
Weight loss >5 kg at presentation Poor appetite, < oral intake Unable to manage usual activities Need steriods at ist presentation Hospital admission at 1st present Long term reliance on opioids for chronic pain Mood disorder on antidepressants
Treatment decisions on IBD have been based on a step up approach.
What are those
At diagnosis, mild anti inflammatory therapy if these tx fail,
Immunomodulating agents are offered. If dse persist
Biologic agents are added
If all of these measures fail, surgery is the last resort
6 main categories treatment to control inflammation to allow GIT opportunity to heal
Aminosalicylates (5 ASA)
Corticosteriods
Immunomodulators (azathioprine, 6MP, methotrexate)
Biologic agents (infliximab, adalimumab, vedolizumab, ustekinumab)
Antibiotics ( metronidazole, ciproflixacin,)
Exclusive enteral nutrition
Mesalazine 5 ASA is the first line tx and is also used to treat mild to moderate sx of active colonic IBD.
Is more useful to treat UC than CD
True or false
True
How do 5 ASA works?
Main use for long term maintenance of remission
Act topically on the colonic mucosa to suppress production of pro inflammatiry mediators and control inflammation
Effective in colonic dse than in small bowel
Can be given orally or rectally
Topical therapy act on the mucosal level
What are the 5 ASA preparation in Australia?
Sulfasalazine
Olsalazine
Balsalazide
Other mesalazine preparations
Those available for rectal use include
Mesalazine enemas )liquid or foam)
Suppositories
Patients must be treated first with sulfasalazine unless allergic to sulfur containing meds
True or false
True
Patients will be offered mesalamine containing 5 ASA which do not have sulfamoity
Combination of oral steriods and 5 ASA may be used in more severe cases
True or false
True
A combination of topical and oral 5 ASA bring Pt’s into remission more quickly that oral tx alone
When is corticosteroids use for?
Are used for moderate to severe active IBD
Use for Pt’s who are not responding to 5ASA tx
Prednisone is considered
Not effective for maintenance therapy
Expect signs of improvement in 3-5 days
Hospital admission is necessary if not responding to steriods
Steriods shoulds be given with what medications?
Immunomodulators such as azathioprine, 6 MP
Corticosteriods side effects includes
Weight gain Susceptibility to infections Acne Facial hair Hypertension Glucose intolerance Diabetes Sleep and mood disturbances Dyspepsia Prolonged use >12wks include cataracts, Osteoporosis and myopathy
Budesonide (oral steriods) are used for what?
Mild ileal or ileocolonic Crohn’s dse
Matrix encased budesonide (cortiment) for mild to moderate colitis
What is the standard of care for the maintenance of remission in both CD and UC?
Long term maintenance therapy
What is immunomodulators?
Drugs that modulate or suppress the immune system ( esp azathioprine, 6MP and methotrexate)
Prevent or reduce corticosteriods dependence in IBD
Slow onset of action not ideal for induction of remission (2-3/12 for optimal response) 6 MO (8-12/52 full dose efficacy) Methotrexate (commence s/c weekly dosing min 6/52 full dose efficacy)
In IBD, what are the first line immunomodulating therapy?
Thiopurines (6MP or azathiprine)
When is immunimodulator started?
Disease assessed endoscopically is clinically severe at onset
Steroid dependence
Second course of steriods for a relapse is needed
Patients avoiding steroids due to obesity, osteoporosis, diabetes steroid induce menta illness
Cycloporins or tacrolimis
Reserved for rescue therapy when there is a severe episode and not responding to high dose IV steroids in hospital
Used as a last resort and prior to colorectal surgical consultation is recommended
Surgery is the next step mgt
Twhat is the aim for immunomodulator therapy?
To achieve and maintain steroid free remission and heal the mucosa
Immunomodulators side effects
Vomitting
Diarrhea
Associated complications include pancreatitis (thiopurines), hepatitis, reduced wbc count, increased risk of onfection.
Biologic treatments is used for what?
Patients with moderate to severe IBD where standard medical tx has been insufficiently effective.
What are the 2 anti tumour necrosis factor (TNF) antibidies available on PBS tx for IBD
Infliximab(Remicade)
Adalimumab (Humira)
Both are effective in patients with UC and CD.
Infliximab is used in hospitalized pations with UC with severe acute colitis and fail to respond adequately to IV cortecosteroids
Itolerance to and inefficacy from aminosalicylates, thiopurines and a course of cortecosteroids.
True or false
True
Adalimimab is used for what?
Chronically active moderate to severe UC
How is infliximab and adalimumab given?
Infliximab is IV infusions
Adalimumab is S/C
These agents blocks immune syatem’s production of TNF, a pro inflammatory cutokine implicated in IBD.
Where is Vedolizumab used?
Approved by PBS for both induction and maintenance therapy for moderate to severe CD and UC
Ustekinumab is used for what
For the management of plaque paoriasis for those who developed psoriatic dse while on anti TNF therapy
Biologic therapy shown highly effective as first line for the tx of IBD
True or false
True
Biologics adverse effects
Infection Malignancy Immunoganicity Infusion reaction Opportunistic infections Reactivation of viral infections Reactivation of or primary infection with tuberculosis Psorias and other paradoxical immune related disorders Worsening of congestive heart failure Demyelinating disorders Malignancy and lymphoma
What is Exclusive Enteral Nutrition?
Administratiin of a liquid nutrition formula to meet all nutritional requirements, replacing normal diet either orally or nasoenteric tine.
When is antibiotics (metronidazole, ciprofloxacin, rifaximin) used?
Effective for the tx of CD complications (perianal dse, fistulas, inflammatory mass, bacterial overgrowth in setting of strictures)
It is used for the tx of pouchitis in UC following proctocolectomy.
What antibiotic has an increased risk of C. Difficile infection?
Broad spectrum antibiitic especially fluoroquinolones such as ciprofloxacin
When is surgey indicated?
When sx no longer controlled and mechanical complications such as strictures, obstructions, perforations, abscess or refractory bleeding.
Resection is not a cure typically will recur post surgery therefore recommend to detect recurrence early is post op surveillance
Metronidazole recommend for 12 wks, thiopurine therapy for those at risk and ideally where available an anti TNF agent for thise at highest recurrent risk
Colonoscopy at 6-12 mos to see if step up in theraphy is warranted to intervene early before the 2 nd resection.
What is TNF?
TNF inhibitors are antibodies made in a lab from human or animal tissue. (Your body makes antibodies to fight off infections.) Once they’re put into your blood, they cause a reaction in your immune system that blocks inflammation.
Your immune system makes a substance called tumor necrosis factor (TNF). Usually, your body keeps your TNF levels steady. But if you have an autoimmune disease like RA, something goes wrong. You start making too much TNF, and that leads to inflammation.
What is IBD?
It is thought to atise from disregulation bet the immune system, host genetics and the complex ecology of the gut.
What is microbiome?
The gut is thought to harbour trillions of bacteria.
Alterations and reduced diversity of microbiome in Pt’s with IBD is DYSBIOSIS
What is the management for recurrent C.Diff?
FMT (faecal microbiota transplantation)
What are the goals for IBD therapy?
Symptoms control and mucosal healing
Assessed either endoscopically or non- invasively with fecal calprotectin and or intestinal ultrasound
A lifelong dse like IBD requires therapeutic drug monitoring for anti TNF and thiopurines in therapies particular.
6 TGN levels above 235 pmol x 10 RBC have been associated with increased likelihood of clinical remission.
However, if it exceeds 5,700 pmolx10RBC it can be associated with what?
Hepatotoxicity.
Therefore, when using with therapeutic 6 TGN while avoiding higher 6 MMP levels where possible
How does Anti TNF and Thiopurines work?
Inactive prodrugs that are metabolised to produce the active nucleotide metabolites 6 thioguanine nucleotides (6TGN) and also 6 methylmercaptopurine (6mmp) which do not confer efficacy.
Maintenance care for established IBD patients not on immunosuppression, what monitoring should be done?
Annual FBE
Biochemistry along with checking weight and asking about general health
If symptomatic preceeding year tx is indicated and prompt fecal calprotectin for active dse
If Pt’s on steroids or had a low bone density, bone monitoring density should be considered
All pt’s should have at least an annual r/v
Recommendation for patients with UC extending proximal to the sigmoid colon or patients with Crohn’s colitis affecting more than one third of the colon and with one or more ff risks factors:
Active dse PSC Fhx of CRC in 1st deg relative < 50 y/o Colonic strictures, multiple inflammatory polyps shortened colon Previous dysplasia
Annual colonoscopy surveillance
Recommendation for surveillance for patients with:
Inactive colitis extending prox to sigmoid colon without risks factors from annual surveillance category
Patient’s with crohn’s colitis affecting more than 1/3 of the colon without other risk factors
IBD patients with family hx of CRC in a 1st deg relative > 50 y/o
3 yearly colonoscopies
Recommendation for patients with prev colonoscopies were histology were normal.
5 yearly colonoscopies
ECCo guidelines for surveillance should take into acct the what?
Risk for dysplasia to progress to CRC between 2 surveillance interventions.
Disease extent should be taken from most extensively histologically confirmed inflammation from all prev colonoscopies
What should be screened for patients with known significant small intestinal Crohn’s dse and how often it should be done?
A yearly screen for malabsorption in cluding iron studies, vitaminD, B12 and folate to avoid complications from malnutrition.
Strategies in managing IBD
Maintaining remission, anticipating problems and thereby preventing complications
Recommendation for surveillance for cancer risk 8 years after the onset of extensive colitis should be?
2-3 years colonoscopy surveillance with biopsies for dysplasia.
What to assess in patients on long term steroid use and weight loss?
DXA dual energy xray absorptiometry to assess bone mineral density
What to check on patients on immune modifiers
Regular weekly or forthnightly blood tests (EUC, FBC, LFTs) while adjusting the dose and regular 3 monthly monitoring while patient on stable therapy.
If patients are not in remission,
What to do?
Prompt referral to specialist- routine bloods and fecal calprotectin yearly useful tool for annual assessment
What is the common complications of IBD?
Anemia is caused by iron def and also by chronic inflammation
Ehat is the most common nutritional problem in IBD?
Iron def that leads to unexplained fatigue/lethargy
Ehat other factors in IBD patients that leads to development of anemia?
Blood loss
Inadequate nutrient intake or absorption
Inflammation on the bone marrow and iron handling/transport.
What is the induction therapy in Crohn’s dse among children?
Exclusive enteral nutritional therapy
Avoidance of prolonged use of steroids given the direct impact on growth and pubertal development
6 monthly height and weight in patients with IBD is recommended among children.
True or false
True
Gast, colon, entero, and radial eus can be used to how many hours?
72 hrs after last processing provided recent microbiological surveillance cultures have been negative.
EUS, DUO and Bronchoscope can be used up to how many hrs?
12 hours after last reprocessing
Rmergency endoscopes eg intibating bronchoscopes that are not sterile and wrapped should be reprocessed how many hours?
72 hes even if not used.this is to ensure that in a time critical emergency they are ready to use.
Endoscopes that are stored horizontally there should be alarm monitored continuous air flow through each channel
True or false
True
Storage cupboards ahould be tall enough to allow endoscopes to hang without touching the floor and are well ventilated
Duo, liear, bronchoscopes and AFER should be tested how often?
Monthly for microbial growth
All other endoscopes and those stored in a wrapped state should be tested how often?
Three monthly for microbial growth.
Water supply filtered to 0.2 microns for manual rinsing should be tested how often?
3 monthly or
Monthly if the water is not filtered.
What is ISO 15883?
AFER design and principles has been updated
A number of chemical germicides are capable of achieving sterilization if used for prolonged periods for eg aldehydebased products a contact time exceeding 3 hours may be required
True or false?
True
Disinfection is not sterilization what is it?
It involves of removing or killing the vast majority but not all microorganisms.
High disinfection is considered adequate for reprocessing of endoscopes because it removes or kill microorganisms regarded likely to cause disease.
High level disinfection processes need to kill all forms of bacteria(gram+ and gram-ve), viruses inc HIV and resitant viruses like polio, fungi (candida), protozoa(giardia)
Hig level chemical alone can kill the more reistant form of bacterial spores and cyst only with prolonged contact time usually 3 hours
Heat alone is alo effective disinfectant for eg temp 70 deg for 100 min are used for pasturisation
True or false
True
What are the factors that warrants the disfrctant to kill all microorganisms?
Adequate removal of biological material through pre-cleaning.
Initial number of microorganisms present- a reduction of microorganisms can be achieved by scrupulous cleaning alone.
Temperature
Recommended temperature is provided on the disinfectant product label glutaraldehyde 25-35 deg, OPA 20-25 deg
Concentration
Chemical concentration should be checked using test strips
Contact time
Minimal time required for biocidal activity based on manufacturers instructions and based on adequately cleaned beforehand
Other factors
Disinfectant ph and relative resistance of the microorganism involved
What are the practical barriers to chemical sterilization?
Staff errors Mechanical endoscope defects Design flaws in AFER Potential for inadequate cleaning Contaminated rinse water
When is bronchoscopes used?
Are feequently used to take samples (BAL) for diagnosis of lung conditions inc culture for bacteria, mycobacteria and fungi.
What is pseudo outbreaks?
Repeated positive results for the same microorganisms from BAL fluid from different patients
Bacteria (salmonella)
Most commonly transmitted by endoscopy.
Mycobacterium tuberbulosis
Relatively resistant to most chemical agents including aldehydes
Non tuberculosis (atypical) mycobacteria are even more resistant to glutaraldehyde.
Cdiff spores are more susceptible to a variety of chemical disinfectants than test spores
Exposure to 10 minutes to 2 percent glutaraldehyde has been shown to inactivate Cdiff spores.
True or false
True
What bacterial species are extremely difficult to remove from the plumbing, AFER and damaged endoscope channels?
Pseudomonas aeruginosa
Is a common hospital oathogen and endoscope and accessories contamination(most likely acquired from the hospital than from prev patients)
No agent can be effective against microorganisms it cannot reach.
True or false
True.
Therefore inadequate cleaning can compromise even prolonged contact time in excess of 60 minutes is unlikely to kill pathogenic microorganisms present on or in the endoscope.
Inadequate cleaning caused disinfection process failed.
What is the most important process of endoscope decontamination?
Scrupulous manual cleaning prior to disinfection.
What is meant by manual cleaning?
Refers to physical tasks performed by hand of removing biological material from the scope with appropriate brush, cloths, detergents and water.
Lightguide plug
Connects into light source.
The air/water and suction channels have ports in light guide plug.
The terminals of it is not waterproof and must be covered with soaking cap supplied prior to cleaning.
Periodical checks should be made to ascertain continuing water tightness of these caps.
Umbilical cable/universal cord
Connects the light guide plug to the body of the scope.
Control head
Contains angulation control handles which allows the operator to flex the instrument, suction and air/water valves for control of air and water flow from the distal too.
Insertion tube
Enters the patient’s body and is grossly contaminated during the procedure.
The distal tip houses the microchip in video scopes, openings for suctions, air/water and jet washing channels and the lens covering the flexible fibre optic light guides.
Bending section is adjacent to insertion tube.
Covering is made up of soft flexible material that is Vulnerable to damage
Cables allow the tip of scope to flex.
A negative leakage test does not exclude damage to internal scooe structures.
True or false
True
What equipment are useful to clean grooved control handles and to brush the distal tip and biopsy ports?
Soft toothbrushes
What does enzymes do?
Digest biological material enhancing removal by brushing and flushing
These products reduce microorganisms load by up to 3 folds.
Enzymatic detergents should used at the correct temperature and concentration. Optimim efficacy when products are used in warm water 35 deg
True or false
True
Conversely, use of hot water >60 deg denature protiens and inactivate enzymes
Many bacteria exists in a planktonic state (free suspension).
What do you call this bacteria?
Biofilm is formed when bacteria adhere to a surface and secrete large amount of polysaccharides to form a protective mattix or film around themselves.
Pseudomonas species, legionella and atypical mycobacteria have the ability to exist either in a planktonic state or to form biofilms.
Biofilms protect the bacteria against brushing, fluid flow and chemical (disinfectant) making microorganisms more difficult to remove.
Biofilms developed in scopes and AFER not detectable by the surveillance culture should be sampled for microbiological surveillance how many hours after disinfection?
12 hrs. As bacteria from superficial layers have been destroyed but within the deeper layers have not.
The final rinse for bronchoscope and duo should be bacteria free and other endoscope should also be of high wuality and free of bacterialnown to cause invadive clinical dse including pseudomonas species.
The water used after manual cleaning and before disinfection does not need to be bacteria free
True or false
True
The filterbanks often in a 3-4 stage filter size arrangement from 10 micron to 0.2 micron absolute final filter.
Where should filter banks be placed?
At the beginning of water delivery and an access point immediately prior to the entry into the AFER.
Disinfectant for use in scooes reprocessing are regulated by who?
TGA
Peracetic acid are used in machine systems in Australia and New Zealand
The recommended contact time will differ if the disinfectant temperature and concentration is higher.
At room temp 20deg how many minutes is the soaking time?
10-20 minutes for glutaraldehyde and OPA in manual systems are usual.
Before leak testing performed what needs to be done to assist in detectingminor leaks arising from cracks in a channel.
Removal of buttons.
Flexing distal tip whilst instrument is pressured will assist in detecting leaks from where?
A rubber of the bending section.
Function of angulation cables should be checked.
Check lens and outer sheath for signs of cracking or damage
As per AS 4187, what is the minimum air exchanges ler hr is required in processing area?
10
Manual cleaning steps following a procedure.
Pre-cleaning
Leak testing
Cleaning- buttons are clean in ultrasonic cleaner
Rinsing
AFER
Dry
Store
TGA advised reprocessing of scopes in the new cleaner disinfector AFER mist be commenced within 1 hour of the procedure. Scopes should never be left soaking for long periods eg overnight.
True or false
True
AFER used as a complete reprocessing machine which performs what?
Leak testing, cleaning, disinfection, alcohol perfusion and drying.
Time after use is critical and must not exceed an hour
Extended storage is only permitted if microbiological results had shown negative.
How long for to store?
Within 12 mos
How often emergency scopes should be routinely reprocessed?
72 hrs to ensure they are ready to be used anytime
If recent cultures have been positive or inadequate storage facilities not available, endoscope should be disinfected if storage time has been longer than 12 hrs
True or false
True
Microbiological surveillance for loan scope should be done within how many hrs?
72 hrs of the receipt of scope
Chemical indicator
Demonstrates that scopes have been subjected to sterilisation process
Surveillance culture of AFER amd scopes as a quality control measure has been recommended by who?
GESA & GENCA since 1995 and endoscopes surveillance by New Zealand expert Committee in 2002
What is quality control marker used in endoscopes and AFER?
Surveillance culture to check the adequacy and completeness of cleaning and disinfection process and structural integrity of the scope.
How often surveillance culture for AFER, duo, linear and bronchoscopes be done?
4 week or every month
All other scopes incl radial should be done every 3 mos
Endoscope that have been reprocessed through a sterilisation cycle and stored in a wrapped state shoul be monitored every how often?
3 mos
Water used for manual rinsing of endoscopes should be monitored every month If filter banks not in use
How often if water is filtered to 0.2 microns?
Every 3 months
Endoscopes on loan to be tested within when?
73 hrs of receipt of the instrument
Microbiological testing should be done after usual processing and following storage of up to 12 hours to allow detection of microorganism arising from a biofilms
True or false
True
