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Misadventures of the Colon Before, During and After Traveller’s diarrhoea Philippe Lagacé-Wiens, MD, FRCPC, DTM&H Otherwise known as…

Misadventures of the Colon

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Page 1: Misadventures of the Colon

Misadventures of the ColonBefore, During and After Traveller’s diarrhoeaPhilippe Lagacé-Wiens, MD, FRCPC, DTM&H

Otherwise known as…

Page 2: Misadventures of the Colon

Transparency declarationsI have nothing to declare relevant to the content of this presentation. In fact, I lead a pretty lackluster life mostly taken up by sleeping, eating, working, making dinner, playing with my kids and spending quality time with my wife.

Therefore I have little time left over to entertain the idea of fancy drug/vaccine dinners or relationships with industry. I have a few good friends, none of them in the pharma/vaccine industry. My wife works for the Public Health Agency of Canada. PHAC has a lot of money recommends a lot of vaccines, but none for traveller’s diarrhoea.

I used to have some stocks in AstraZeneca but got rid of them because the dividend sucked and value never increased. In 2006, I got an unrestricted travel grant from Sanofi-Pasteur (which used to sell Dukoral™) for $500 and in 2007 I gave an educational session about antibiotic resistance to a group from Bayer (Cipro™) for which I got $500.

All that being said, I have no financial relationships with either at this point in my life.

Outline Traveller’s diarrhoea background

Pre-travel advice and prevention of traveller’s diarrhoea.

Treatment of traveller’s diarrhoea.

Sequelae of traveller’s diarrhoea and their management.

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Diarrhoea or diarrhea?

Etymology The term comes from the Greek, which means “through” “flow” The Romans adopted the term into their language using the roman alphabet as, “diarrhœa”, the “rh” being retained as it preserved the phonetic character of the letter “rho” () and the œbeing the phonetic equivalent of the Greek “”.

Words adopted to English from Old French and Medieval Latin (usually in the 12 -14th

century) did not retain the œ (eg: cemetery: Latin cœmeterium, Greek koimeterion) while words directly taken from Classical Latin at a later date (much of medical terminology) tend to keep the original Latin spelling.

In modern American English, diarrhea is used, but makes little etymological sense, as the Latinized Greek origins are retained in the “rh” but not the “œ”. If a more American English phonetic spelling was desired, “diarria” would be more appropriate (and in keeping with the way French altered Latin spelling prior to inclusion in English language).

The British English uses the more conservative Latin spelling diarrhœa which is in keeping with the etymological origins of the word albeit not in keeping with Canadian and American phonetic pronunciation of the word. I use diarrhœa, because it is it is etymologically accurate and reasonably phonetically accurate as opposed to diarrhea, which is neither phonetically or etymologically accurate.

In short, you’re not wrong either way.

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Background - epidemiology Traveller’s diarrhoea affects 30-40% of travelers to developing countries (some say up to 60%)

15-20 million per year, or 40,000/day. Usually occurs 4 – 7 days after arrival, 90% of cases in 14 days.

High, medium and low risk areas are well documented.

No significant seasonality

No change over time except in southern Europe, Tunisia, select Caribbean destinations.

Clin Infect Dis 2005; 41:S536–40Infect Dis Clin N Am 26 (2012) 691–706

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Clin Infect Dis 2005; 41:S536–40

Background – risk factors Destination and location of stay seems to have biggest impact. Risk parallels hygiene measures in place.

“5 star” hotels appear to have higher risk.

“Beach holidays” < Tours < Adventure travel

“All inclusive” tours appear higher risk.

Age (younger), residence in a developed country.

Genetic factors

Anchlorhydria

Clin Infect Dis 2005; 41:S536–40

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Impact Classic traveller’s diarrhoea is not life threatening.

~25% have >6 watery bowel movements per day.

30-50% will be unable to pursue planed activities.

Incapacitation lasts a mean of 12-24 hours.

Symptoms last a mean of 4 days and 50% of patients are symptom free at 48 hours without treatment.

Clin Infect Dis 2005; 41:S536–40Infect Dis Clin N Am 26 (2012) 691–706

Causes of traveller’s diarrhoea Identified in 30-50% of cases.

Wide variation exists by region.

Bacterial pathogens predominate (70-80%)

Viral pathogens follow (10-20%) followed by protozoan (5 – 10%)

Infect Dis Clin N Am 26 (2012) 691–706

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Before you go!

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Pre-travel advice and prevention Key points: Destination is the biggest factor in development of traveller’s diarrhoea. Behavioural strategies have limited value. Vaccination of limited benefit. Chemoprophylaxis is recommended only in very limited situations. Universal provision of self-initiated therapy is controversial but has

significant support.

Counselling about risk Counselling about risk should focus on two parts: Risk of disease and risk of negative outcomes.

Risk of disease primarily related to destination. Age, style of travel, achlorhydria, medication (eg. PPIs), genetic factors,

immunocompromise are additional considerations.

Negative outcomes: Acutely related to infection (dehydration, shock). Primarily associated with medical co-morbidities, age. Personal-social (trip interruption, elite athletes, “elite” business travellers). Persistent symptoms after acute illness.

Clin Microbiol Rev. 19:583–594

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Before you go…Prevention of TD Prevention strategies have generally focussed on: Behavioural strategies/avoidance of risk. Antimicrobial chemoprophylaxis Non-antimicrobial chemoprophylaxis Vaccination

Behavioral prevention – Fact or Fiction? Despite 50 years of studying TD, there is no evidence that the adage “Boil it, peel it, cook it or forget it” actually works.

Most studies have shown no relationship between these practices and reduced risk.

Some studies have shown strict adherence to precautions increases risk Others show risks associated with traditionally “safe” products and protective effect of

“risky” products.

Only one quality study has shown a possible benefit of avoiding “dietary mistakes” but no reliable patterns in risk behaviors was seen.

Eating location (home versus out) appears to be a very important factor.

Clin Infect Dis 2005; 41:S531–5

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Summary While intuitive, no evidence strongly supports this approach and data is conflicting.

Destination remains the big risk factor.

It may be that the effect cannot be observed because >95% of travellers cannot follow precautions.

Preparation of food in your own kitchen may be to only way to adhere to adequate precautions.

Clin Infect Dis 2005; 41:S531–5

What to tell travellers (opinion slide!) The only reliable way to adhere to recommended precautions is toprepare your own food/water in a sanitary way. Few foods are reliably safe when not self-prepared: Carbonated or acidic (pH<5) beverages. Very sweet condiments/candies,

pickled foods, most alcoholic beverages, fully cooked steaming hot food (>60C) (not reheated), bread and dry baked goods, intact fruit with a peel.

Anything that has been boiled, cooked, baked, chlorinated/treated, peeled is safe, but post treatment handling dramatically increases risk.

Dr. Phil’s modification of, “Boil it, peel it or cook it yourself and don’t eat out at all” might work better but is impractical

Page 11: Misadventures of the Colon

Antimicrobial chemophrophylaxis Studies in the 70s and 80s clearly demonstrated the effectiveness of antibiotic prophylaxis.

Doxycycline and co-trimoxazole reduced incidence by 50 – 95%

Effectiveness declined dramatically with emergence of resistance.

Quinolones (ciprofloxacin, levofloxacin) subsequently shown to have >90% effectiveness.

Widespread emergence of resistance in multiple pathogens to important class of drug, systemic side effects remain a huge issue.

Clin Microbiol Rev. 19:583–594Clin Infect Dis 41:S553-6Clin Infect Dis 41:S571.6

Rifaximin for prevention Semi-synthetic rifamycin antibiotic.

Negligible absorption, local effect, active against ETEC and other non-invasive bacteria.

Multiple studies show effectiveness in reducing incidence of TD from 25 –72% (overall, ~60%).

Potential advantages include poor absorption with fewer systemic side effects, safe in trials and low risk of clinically important resistance.

Disadvantages include lack of evidence for causes of invasive diarrhoea, little activity against Campylobacter, cost and potential for emergence of resistance in enteric flora.

J Travel Med 19:352–356Clin Infect Dis 41:S571‐6Gastroent Hepatol 7:88‐95Antimicrob Agents Chemother. 45: 643–644

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Antimicrobial prophylaxis – Who? Generally not recommended for travellers. Self-limiting disease, short duration. Risk of side-effects (yeast infections, C. difficile,

adverse drug events, drug interactions) Development of clinically important resistance a

personal and population risk. Availability of good treatment options that limit disease

to a few hours to a day. Limited situations warrant consideration: Higher risk or more severe disease:

immunocompromised, IBD, insulin-dependent diabetics, diuretics, achlorhydria, PPIs, gastrectomy.

Possibly elite/critical travellers (diplomats, business/athletes).

Availability (in some places) of rifaximin may change these recommendations

J Travel Med 19:352–356Clin Infect Dis 41:S571‐6

Antimicrobial prophylaxis – How? Very few people should be offered this option.

For travellers to areas outside South Asia and South East Asia: Rifaximin (where available) 200mg BID. Ciprofloxacin 500mg daily

For travellers to SE or South Asia: Azithromycin 500mg daily.

Should not be given for more that 3 weeks and should start before exposure and end ~2 days after exposure.

Clin Microbiol Rev. 19:583–594J Travel Med 19:352–356Clin Infect Dis 41:S571-6

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Non-antimicrobial prophylaxis Appealing because they may be effective while perceived as limiting potential side-effects and antibiotic resistance.

Bismuth subsalicylate, “probiotics” and tannin albuminate plus ethacridine lactate have shown benefit.

Clin Infect Dis 41:S557-63

Bismuth Subsalicylate Acts as an antibacterial and anti-inflammatory.

Pepto-bismol™ tablets (two tablets four times per day) reduces incidence of TD by ~65%.

Side-effects usually minimal – black stools, constipation.

Tinnitus may be significant and bothersome.

Not usually given to children or adolescents due to fears of Reye syndrome, but ample evidence suggests safety in treatment of acute diarrhoea.

Should not be patients on warfarin and platelet inhibitors.

Liquid preparation prevents absorption of doxycycline and ciprofloxacin.

Clin Infect Dis 41:S557‐63

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Probiotics Lactobacillus GG taken daily starting 2 days prior to departure to a variety of destinations for the duration of travel reduced incidence of TD by 12-47%.

Saccharomyces boulardii has also been shown to have modest but statistically significant benefit in reducing incidence.

Both are considered safe in travellers.

More research needed, but results with Lactobacillus are encouraging and could fit into routine recommendations for travellers.

J Travel Med. 4:41‐43.Clin Infect Dis 41:S557‐63

Tannin albuminate plus ethacridine lactate Antidiarrhoeal adsorbent available in Europe only.

Has been shown to reduce incidence if TD by 36% in a group visiting Egypt.

Role limited by unavailability and lack of evidence in multiple settings.

Clin Infect Dis 41:S557‐63

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Vaccination No universal vaccine exists, primarily due to variety of pathogens.

Dukoral™, a vaccine for the prevention of cholera contains a recombinant B subunit of cholera toxin which has homogy with ETEC LT toxin.

Dukoral™ vaccination has been shown result in a 50-60% reduction in TD caused by ETEC.

Data oft quoted as effectiveness for TD

Clin Microbiol Rev. 19:583–594Infect Dis Clin N Am 26 (2012) 691–706

Limitations of CTB/Whole cell vaccine At best, vaccine is ~50% effective for ETEC diarrhoea.

At best, ETEC accounts for ~30% of TD. ~7% in South East Asia!

The overall benefit of vaccine has been estimated at preventing 7% of TD cases.

Especially ineffective for TD in South East Asia.

Effective only for ~3 months.

Infect Dis Clin N Am 26 (2012) 691–706J Travel Med 2009;16(3):149–60.Lancet Infect Dis. 2006 Jun;6(6):361-73

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Vaccination – for who, and when? Vaccination is safe, but effectiveness is limited.

Possibly recommended for individuals at higher risk of developing ETEC disease or complications travelling to locations with a high proportion of ETEC-associated TD.

Infect Dis Clin N Am 26 (2012) 691–706

Vaccination - future New targeted ETEC vaccines (oral, live attenuated, whole cell and toxin based) are being studied.

Initial findings promising.

Campylobacter vaccines are being studied, but represent a huge challenge.

Norovirus vaccines are also under development.

Infect Dis Clin N Am 26 (2012) 691–706J Travel Med 2009;16(3):149–60.

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If you really got to go!

Treatment of TD Treating traveller’s diarrhoea requires a structured approach: Establish diagnosis and severity. Initiate appropriate treatment. Seek medical care when required.

Page 18: Misadventures of the Colon

Establishing the diagnosis Study definition: Passage of at least three unformed stools within a 24-h period, in

association with at least one symptom of gastrointestinal disease such as nausea, vomiting, fever, abdominal pain or cramps, tenesmus, fecal urgency, or the passage of bloody or mucoid stools.

By convention, it usually refers to disease that develops in a resident of the industrialized world who travels to a developingtropical or semitropical country. Severity usually established by frequency of stool (e.g. >6/day or >3/8 hours or presence of fever and blood in stool)

Clin Microbiol Rev. 19:583–594Infect Dis Clin N Am 26 (2012) 691–706

Appropriate treatment Three parts: Fluid and electrolyte support Antimotility and antisecretory drugs Antibiotic therapy

Clin Microbiol Rev. 19:583–594Infect Dis Clin N Am 26 (2012) 691–706

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Fluid and electrolyte replacement Especially important in children, pregnant women and elderly travellers.

At the onset of symptoms, salted crackers, carbonated noncaffeinated beverages, canned fruit juices, purified water, and clear salty soups are considered appropriate fluid support.

Commercial ORS or “home made”equivalents are acceptable but not required unless illness is severe.

Complex carbohydrates (“rice based”) ORS is better than glucose-based.

Clin Microbiol Rev. 19:583–594

Antimotility agents Loperamide is the agent of choice due to high effectiveness, safe profile and wide availability.

Narcotic preparations, atropine combinations may have serious adverse effects and are not recommended.

Bismuth subsalicylate is effective, but has more adverse effects than loperamide.

SP-303 (a botanical extract) and zaldaride are also as efficacious as loperamide but difficult to obtain.

Clin Microbiol Rev. 19:583–594Infect Dis Clin N Am 26 (2012) 691–706Clin Infecti Dis 2005; 41:S557–63

Page 20: Misadventures of the Colon

Loperamide Effective alone for the treatment of mild to moderate traveller’s diarrhoea (<5 BMs per day).

Can be used in combination with antibiotics with additive benefit in more severe cases.

Usually given as a 4mg loading dose followed by 2mg with every loose movement, but modifications of dosing exist.

Loading dose is important for benefit.

Clin Microbiol Rev. 19:583–594Clin Infecti Dis 2005; 41:S557–63

Self-initiated antibiotic therapy There is no doubt that antibiotics reduce the duration and severity of TD.

Ample studies demonstrated the early benefits of doxycycline and TPM-SMX, and later fluoroquinolones, azithromycin and rifaximin.

Infect Dis Clin N Am 26 (2012) 691–706Clin Infect Dis 41:S553‐6

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Proven antibiotic treatments Three drugs/classes have demonstrated benefit currently:

Fluoroquinoles (ciprofloxacin, levofloxacin, norfloxacin, ofloxacin).

Azithromycin Rifaximin

All have been shown equivalent in reducing duration of symptoms from 50 – 95 hours to 16 – 30 hours.

Reduced effectiveness of rifaximin and fluoroquinolones has been demonstrated in South East Asia, where resistance to these agents in TD pathogens is high.

Clin Microbiol Rev. 19:583–594Infect Dis Clin N Am 26 (2012) 691–706

Self-initiated therapy – the potential benefits Obvious benefits: Reduced duration of illness. Restoration of function. Reduced risk of complications (especially in

children, those with co-morbidities. Psychological benefits

Theoretical benefit: Reduced risk of developing post-infectious IBS. –

not demonstrated.

Clin Microbiol Rev. 19:583–594Infect Dis Clin N Am 26 (2012) 691–706

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Self-initiated therapy – the potential risks Relatively mild, self-limited nature of TD means a discussion on risks of treatment is warranted.

Systemic antibiotics create large alteration in normal floral: Risk of yeast infections/thrush – compounded by tropical

destination. Risk of C. difficile (especially with fluoroquinolones) has been

demonstrated even with short courses for TD.

Drug interactions may be a significant problem with both azithromycin and fluoroquinolones.

Risk of no benefit (antibiotic resistance is high in many regions and unknown in many)

Risk of colonization with multidrug resistant organisms and later difficult-to-treat infections.

Clinical Infectious Diseases 2008; 46:1060–3

Other risks Common side effects: Ciprofloxacin: Rash, photosensitization, dizziness,

insomnia, blurry vision, nightmares, nausea/vomiting (5%).

Azithromycin: Nausea/vomiting (10%), dizziness, insomnia, tinnitus.

Rare but potentially serious side effects: Ciprofloxacin: SJS, Bullous pemphogoid, anaphylaxis,

acute renal failure, liver failure, achilles tendon rupture, tendinitis, cardiac arrhythmias, pancytopenia, hypoglycemia, psychosis.

Azithromycin: SJS, Bullous pemphogoid, anaphylaxis, cardiac arrythmias, hepatic failure, depression.

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Rifaximin – a new paradigm? Non-adsorbed antibiotic with documented effectiveness in treating uncomplicated TD.

Less impact on fecal and other flora, no significant systemic adverse events as absorption is negligible.

As effective as ciprofloxacin for treatment of uncomplicated TD (primarily due to ETEC).

Less effective against dysenteric diarrhoea.

No activity against Campylobacter.

Clin Microbiol Rev. 19:583–594Infect Dis Clin N Am 26 (2012) 691–706Clin Infect Dis 41:S571‐6

Self-initiated therapy – the reality There are no “rules” as to who should be offered self-initiated therapy.

Recommendations vary by physician and experience.

Effective does not equate recommended.

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Self-initiated therapy – the reality Most try to balance the real benefits with the risks of antibiotic therapy. Consider individual and population risks.

Depends on the type of travel, destination, access to medical care and client.

General rules: Minimize duration of antibiotic exposure Use with anti-motility agents Limit treatment to moderate to severe cases (eg. >3 watery

movements in 8 hours with other GI symptoms).

Treatment regimens 3 day treatments: Ciprofloxacin 500mg BID x 3 days. (Not in SE Asia and possibly South Asia!) Azithromycin 500mg OD x 3 days Rifaximin 200mg TID x 3 days (where ETEC is more likely)

Single dose treatments: Ciprofloxacin 750 – 1000mg OD x 1 (Not in SE Asia and possibly South Asia!) Azithromycin 1000mg OD x 1

Hybrid treatments Start with 3 day treatment but discontinue as soon as symptoms resolve.

Clin Microbiol Rev. 19:583–594Infect Dis Clin N Am 26 (2012) 691–706

Page 25: Misadventures of the Colon

Infect Dis Clin N Am 26 (2012) 691–706

Gastroenterol Hepatol. 2011;7:88‐95

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Duration Most studies demonstrate equivalence between 3 day and one day treatments for azithromycin and fluoroquinolones.

Some studies suggest that more severe or complicated TD (high fever, bloody stool) should be treated with 3 days.

Clin Microbiol Rev. 19:583–594Infect Dis Clin N Am 26 (2012) 691–706

Probiotics for treatment Probiotics have demonstrated benefit for treatment of acute diarrhoea.

Most studies in children Most studies with Lactobacillus GG.

Most studies show reduced duration and severity of illness, and reduced risk of persistent diarrhoea.

No studies for treatment of traveller’s diarrhoea.

Safe, and can be considered as alternative or adjunctive to pharmacological agents.

Clinical Infectious Diseases 2008; 46:S96–100

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TD treatment in children Data for treatment of TD is extremely scarce. Mainstay of therapy is oral rehydration. Treatment to shorten duration of illness has benefits, but not widely advocated. Lack of definitive recommendations. Loperamide shown to be effective with little risk of adverse effects in

children >24 months. Azithromycin is effective for treatment and safe in children. Cefixime also

effective and safe. Rifaximin is safe in kids >12 years.

Clinical Infectious Diseases 2005; 41:S547–52

After the storm

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Post gastroenteritis complaints Persistent gastrointestinal symptoms are a common complaint in patients who experienced TD abroad.

3% have symptoms >30 days

Across studies 5 – 32% of episodes of acute gastroenteritis are associated with persistent symptoms fitting criteria for IBS.

Traveller’s diarrhoea has specifically been associated with a 5x increased in risk of developing IBS

World J Gastroenterol 2009 15(29): 3591‐3596Clinical Infectious Diseases 2005; 41:S577–86Clinical Infectious Diseases 2006; 43:898–901

Causes of persistent symptoms Persistent infection or co-infection

Temporary post-infection phenomena Lactose intolerance SIBO

Malabsorbtion syndromes

Post-infectious IBD

Post-infectious IBS

Clinical Infectious Diseases 2005; 41:S577–86

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Investigations Extent of investigations will depend on severity, duration and associated symptoms.

Investigations should attempt to identify a reversible cause.

Possible Investigations Stool for ova and parasites.

Stool for bacterial culture in sub-acute cases or where carrier state is suspected (and relevant).

C. difficile toxin assay

Lactulose or glucose breath tests or small intestine quantitative culture.

Investigations coeliac disease (tissue transglutaminase or endoscopy) and IBD.

Evaluation for anemia or nutrient deficiencies.

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Co-infection or persistent infections Most commonly attributed to protozoa.

Giardia intestinalis, Dientamoeba fragilis, Blastocystis hominis, Cyclospora, Cryptosporidium and Entamoeba histolytica may all be implicated in persistent symptoms.

Bacterial carriers states not usually symptomatic.

Patients with persistent symptoms who have received an antibiotic in past 6 months should be tested for C. difficile toxin

Clinical Infectious Diseases 2005; 41:S577–86

Temporary post-infection phenomena Persistent gut damage after infection can lead to symptoms.

Intestinal disaccharidase deficiency may lead to temporary sugar intolerance.

Small intestinal bacterial overgrowth (SIBO) increasingly considered important in post-infectious diarrhoea.

Clinical Infectious Diseases 2005; 41:S577–86

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SIBO Enteric infections may lead to altered bowel motility Overgrowth of bacteria in the small intestine.

Overgrowth leads to malabsorption and resulting diarrhoea.

Strong links exist between IBS and SIBO, with 84% of IBS patients having SIBO and 75% improving with antibiotic therapy directed at SIBO.

There may be a significant role of SIBO in persistent symptoms after TD.

Treatment with antibiotics is potentially curative.

Clinical Infectious Diseases 2005; 41:S577–86

Malabsorbtion syndromes Classic malabsorption syndrome associated with travel is tropical sprue. Very rare in vacationers. Usually significant weight loss and wasting. Responds to prolonged antibiotic therapy.

More commonly, TD “unmasks” coeliac sprue. Symptoms mild to severe. Diagnosed with biopsy or tissue transglutamidase antibody. Treatment is with gluten avoidance.

Clinical Infectious Diseases 2005; 41:S577–86

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Post-infectious IBD Traveller’s diarrhoea may be the trigger that leads to the diagnosis of Crohn’s disease or ulcerative clolitis.

No evidence that TD has an aetiological role.

Occurs in genetically predisposed individuals.

Diagnosis suspected in patients with systemic symptoms, weight loss, persistent hematochezia.

Diagnosis is usually by colonoscopy.

Clinical Infectious Diseases 2005; 41:S577–86

Traveller’s diarrhoea and IBS Post-infectious-IBS is a recognized complication of traveller’s diarrhoea.

Occurs in 5 – 30% of cases, depending on the cause.

Seems to correlate with duration and severity acute of disease.

No single pathogen implicated Campylobacter, Shigella, Salmonella and

Escherichia coli 0157:H7 are known to be associated.

Not typically associated with non-inflammatory or viral pathogens. World J Gastroenterol 2009 15(29): 3591‐3596

Clinical Infectious Diseases 2005; 41:S577–86

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PI-IBS - Diagnosis Requires ruling out alternative causes of symptoms.

Usually presents with persistent waxing and waning diarrhoea-predominant complaints attributable to an acute gastro-enteritis.

Function normal prior to infection. No weight loss, systemic symptoms or persistent rectal bleeding.

Rome criteria for formal diagnosis.

PI-IBS - Pathophysiology Patients with PI-IBS have persistent elevations in inflammatory markers in the gut:

Elevated inflammatory cytokine levels. Higher numbers of mucosal T

lymphocytes Higher numbers of enterochromaffin

cells. Abnormalities are absent from those whose symptoms resolve completely.

Some studies suggest increased gut permeability.

Associated with genetic variants in immune function.

World J Gastroenterol 2009; 15: 3591-3596.Clinical Infectious Diseases 2005; 41:S577–86

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PI-IBS - Prevention Prevention of inflammatory diarrhoea would likely prevent PI-IBS.

Role of chemoprophylaxis using antibiotics controversial due to risks.

Role of rifaximin debatable, since Campylobacter is a major cause of PI-IBS. No data published.

No vaccines available.

Early treatment of TD would reduce duration and severity of TD (both risk factors for PI-IBS)

Not proven, but often used to support use of self-initiated treatment.

Clinical Infectious Diseases 2005; 41:S577–86

PI-IBS-Treatment Historically similar approach to IBS.

Elimination diets, increasing dietary fiber, digestive enzymes, and probiotics benefit some people.

Symptomatic management: Judicious use of antispasmotics (scopolamine, hyoscyamine) and loperamide. Low dose tricyclic antidepressants (amitryptaline) antagonizes serotonin and

acetylcholine. Specific serotonin antagonists (metaclopromine, ondansetron, granisetron) may

be helpful.

Steroids not helpful

World J Gastroenterol 2009; 15: 3591‐3596 Clinical Infectious Diseases 2005; 41:S577–86

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Antibiotic treatment for PI-IBS? Since SIBO with reduced gut motility is seen in a proportion of patients with IBS, antibiotic treatment may alleviate symptoms.

Luminal antibiotics (neomycin, rifaximin) have been shown to improve symptoms of IBS and normalize lactulose and glucose breath tests.

Remains controversial but evidence is strong for antibiotics playing a role for some forms of IBS.

Promotility agents (erythromycin, tegaserod) may also play a role.

Further studies are needed to evaluate impact of antibiotics on PI-IBS.

Curr Gastroenterol Rep (2012) 14:439–445N Engl J Med. 2011;364(1):22–32. Clinical Infectious Diseases 2005; 41:S577–86Gastroenterol Hepatol (N Y). 2009;5:435‐42

PI-IBS - prognosis Gradual resolution of symptoms in most patients.

The largest and longest prospective study of PI-IBS, the prevalence of persistent PI-IBS was:

31% at 2 years 23% at 4 years 17% at 6 years.

Gastroenterology 2007; 132: A66

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Summary Prevention: Limited value of behavioural strategies Lactobacillus GG probably works Antibiotics, BSS and/or vaccination in limited groups.

Treatment Hydration/electrolytes Antimotility (loperamide) Antibiotic – short course, right antibiotic – may prevent PI-IBS

Sequelae Investigate potential causes (protozoa, IBD) Possible role of antibiotics for SIBO/IBS Symptomatic management Prognosis is slow improvement.

Questions?