© 2018 Sharon Erdrich

Testing for Small

Intestinal Bacterial

Overgrowth (SIBO)

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Sharon ErdrichMHSc (Hons), DipNat, DipHerbMed, DipAroma, NZRN.

TOPICS

1. Intro to SiBO Clinical Presentation of SiBO

2. Options for Diagnosis

3. SiBO Treatment Guideline

4. Case Examples

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SIBO – definition

• SiBO = Small Intestinal Bacterial Overgrowth• “an increase in the number and/or alteration in the type

of bacteria in the upper gastrointestinal tract”

3

World J Gastroenterol 2010; 16(24): 2978-2990JAMA. 2004;292(7):852-858Am J Gastroenterol. 2000; 95:3503-3506.

• Link between IBS & SIBO• High prevalence of bloating in IBS (~92%)• Gut-produced gases are a leading cause of bloating, pain and altered

gut transit

• 84% of IBS patients have abnormal lactulose breath test → 75% improvement of IBS symptoms after eradication of SIBO

• antibiotic-sensitive pathophysiology of IBS

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JAMA. 2004;292(7):852-858

Recent proposal that IBS be renamed “Irritable Bowel Symptoms”, as most cases of IBS have an underlying (and mostly treatable) cause.

Brown, Ben (ND) 2018 ICNM London

Clinical Presentations Suggestive of SiBO

• Irritable Bowel symptoms• Abdo pain• Constipation and/or diarrhoea• Urgency

• Burping, Reflux

• Food intolerances /acquired food “allergies”• Includes suspected malabsorption syndromes

• Histadelia

• Intolerance to fermented foods

• Worse for probiotics, prebiotics or fibre supplementation

• Nutrient deficiencies - in spite of adequate intake (esp. iron, B12)

• Weight loss, weight gain – in spite of appropriate intake

© 2018 Sharon Erdrich

SiBO May be a Factor in:

DIET HISTORY

• Better on Paleo diet/worse on Vegan

• Carbohydrate-rich diet

• Dairy intolerant

• “Food confusion”

• Fructose intolerant

• Gluten/grain intolerant

• Multiple Food intolerances

• Worse for fibre

OTHER

Brain fog

Headache

Joint pain, incl. arthritis

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DIGESTIVE DYSFUNCTION

Leaky gut

GIT dysmotility (ANY)

Burping/reflux

Ileo-caecal reflux

Crohn’s disease/Colitis

Coeliac disease

Malabsorption syndromes

Worse for prebiotics

Worse for probiotics

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DISEASES/CONDITIONS

Cirrhosis, Fatty Liver

Distal bowel problems

Diabetes

Fibromyalgia

Immunodeficiency states

Mood/psychiatric disorders

MS, Alzheimers, Parkinson’s

Pancreatitis

Pelvic inflammation (BV, UTI etc)

Renal failure

Rosacea, Psoriasis

SiBO can occur due to loss of function of Natural Defences

• Normal GI Secretions• Gastric acid, Bile, Pancreatic enzymes

• Serotonin, Motilin & Others – Affect motility

• Alteration in one or more of:• Anatomy• Normal motility • Normal flora balance• +/- Combination of any of a number of risk factors

• Immune function• Normal flora• Intestinal immunoglobulins

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World J Gastroenterol. 2010;16(24):2978-2990. Gastroenterol Hepatol (N Y). 2007 Feb; 3(2): 112–122.

© 2018 Sharon Erdrich

Risk Factors for the Development of SIBOANATOMIC

Small intestine diverticula

Small intestine strictures (radiation, medications, Crohn's disease)

Surgically created blind loops

Resection of ileocecal valve

Fistulas between proximal and distal bowel

Gastric resection

Mal-rotated bowel

IRRITABLE BOWEL SYNDROME

Multiple factors (eg Post-infectious, which can cause motility disorder)

ORGAN SYSTEM DYSFUNCTION

Cirrhosis, Fatty Liver

Crohn's disease

Coeliac disease

Gastric resection

Immunodeficiency states

Malnutrition

Pancreatitis

Distal bowel problems

MEDICATIONS

Anticholinergics

Gastric acid suppressants

Opiates

Recurrent antibiotics

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MOTILITY DISORDERS

Gastroparesis

Small bowel dysmotility

Chronic intestinal pseudo-obstruction

Ileo-caecal reflux

Trauma – eg: abdominal or head injury

MEDICATIONS

Recurrent antibiotics

Gastric acid suppression

OTHER DISORDERS

Diabetes

Hypochlorhydria

Recurrent vomiting (egBulimia)

ELDERLYGastroenterol Hepatol (N Y). 2007 Feb; 3(2): 112–122.

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HISTORY

Past abdominal surgery

Multiple abx in history

Worse for antibiotics

Better for antibiotics

Onset following gastro/travel bug

Small intestine diverticula

Radiotherapy (to abdomen or pelvis)

Use of opiates

Use of gastric acid suppression

Endometriosis

Stasis

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MMC Dysfunction

• PHx of Clostridium, Giardia, Lyme disease

• Scleroderma

• Diabetes

• Hypothyroid conditions

• “Pseudo-obstruction”• Abdominal surgery• Chronic endometriosis• Abdominal trauma

• Head injury

• Medications• Opiates, Antibiotics, Anticholinergics

• Stress

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Am. J. Gastroenterol.2016. 111, 93–104

http://library.med.utah.edu/WebPath/GIHTML/GI030.htm

Adhesions between loops of small intestine

Flora Distribution in SiBO

11JAMA. 2004;292(7):852-858.

DISTRIBUTION OF INTESTINAL BACTERIAL FLORA IN NORMAL GUT

AND IN SMALL INTESTINAL BACTERIAL OVERGROWTH

26cm 2.5m 3.5m

THE SIBO CYCLE

SIBO

Host eats carbohydrates

Carbohydrates exposed to Bacteria

prematurely

Fermentation

Food = Survival & Proliferation

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START HERE

Predisposing

Factors

GI SYMPTOMS

+/- extra-gastrointestinal manifestations

• Gut inflammation

• ↑LPS

• Brush border damage

• Intestinal permeability

• Bile deconjugation

GAS

SIBO

Clinical Presentation• Postprandial bloating

• Abdominal distension

• Altered gut motility – or normal

• Visceral hypersensitivity

• Abnormal brain-gut interaction (memory issues, brain fog, sleep problems etc)

• Autonomic dysfunction, and

• Immune activation

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JAMA. 2004;292(7):852-858. doi:10.1001/jama.292.7.852.

Clinical Presentation• Multiple food intolerances

• Commonly: apples, dairy, onion, cabbage, grains, legumes• And/or confusion about what does/doesn’t aggravate

• Carbohydrates &/or fats• food not my friend

• Leaky gut - Changes in barrier function• implications for nutrient absorption• systemic manifestations associated with increased absorption of

luminal endotoxins→Calorie-deficit

• Alterations in body composition

14World J Gastroenterol. 2010 Mar 7; 16(9): 1057–1062

Hyperpermeability is Caused by SiBO

• Damage to the intestinal mucosa

• Bacteria, their biofilms and toxic by-products can all damage the lining of the small intestine

• Impairs nutrient absorption

• Increases intestinal hyperpermeability.

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Clinical Presentation

• Weight loss• Weight gain• Inflammation• Brush border damage

• Malabsorption• Hyper-permeability

• Nutrient deficiencies• Bile deconjugation

• Fat malabsorption

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Bile Salt Malabsorption (BSM)

• Functional diarrhoea / IBS-D assoc w/ BSM (~25% to 50%)

• Bacterial overgrowth in jejunum

→Fat malabsorption→Fat soluble vitamin deficiencies

→Urgency, early morning diarrhoea

→Burning on defaecation

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J Lip Res. 2006, 47; 241-259.Gut and Liver. 2015, 9;3.

• Confirm presumptive diagnosis• Determine the gas – guides treatment protocol• Determine the gas pattern – indicates area of dysfunction

(so “collateral damage” can be mitigated – eg proximal more likely to be histadelic, simple carb intolerant)

• Enhances client understanding• Increases compliance with treatment

• Can evaluate changes• Measure of colonic flora activity

Why test for SiBO?

How to diagnose SIBO

1. Jejunal aspirate and culture

2. Hydrogen-Methane Breath testing• Humans can not make Hydrogen or Methane

• ONLY produced by bacteria• Any gases produced following ingestion of a

sugar MUST be coming from bacterial fermentation, so testing at intervals can track this.

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Indications for Breath testing

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Am J Gastroenterol 2017; 112:775–784

Performance of breath tests6. We suggest that the presence of bacterial overgrowth should be ruled out before performing lactose or fructose breath testing. (100% agreement)

Why is the Gas Important?• Hydrogen

• Associated with diarrhoea• Visceral sensitiser• 100% correlation to fibromyalgia

• Methane• Normally produced by colonic flora• Associated with constipation

• Hydrogen sulphide• To date not measurable• Olfaction is best diagnostic tool

• Can have any combination of the above.

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J Neurogastroenterol Motil, 2010, 16; 2

Choosing the Substrate

GLUCOSE

• 98% specific for SIBO but just 27% sensitivity • was compared to jejunal aspirate• ie – only correlates to proximal SIBO

• Hence the low sensitivity – will give false negative if SiBO occurs after first few feet of SI.

• RECOMMENDATION:• Glucose is best for those with significant reflux, eructation within 30-60 mins

of eating• Never in diabetics• MUST use if dairy ALLERGIC (not intolerant)

• Dose: 1g / kg up to 100g max dose.

22Eur J Gastroenterol Hepatol. 2014 Jul;26(7):753-60

Choosing the SubstrateLACTULOSE• a synthetic sugar

• Humans lack ability to digest (no enzyme)• Dose: 10g (15mL) in 250-300mL water

• False positive is common – depends on transit time of individual

• Enables observation of flora activity from mouth to colon

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Testing for Malabsorption• Breath tests are also used to diagnose:

• Lactose intolerance• Fructose malabsorption• Sucrose malabsorption• Must rule out SIBO first

• These sugars normally absorbed in duodenum and proximal jejunum

• Testing protocol is similar – ask!

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Preparation for Breath Testing

25Am J Gastroenterol 2017; 112:775–784

Preparation for Breath Testing

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• Stop antibiotics 4 weeks before

• Stop herbal antimicrobials minimum 2 weeks before

• Stop pro & prebiotics minimum 1 week before• Diet prep 24 hours – non-fermentable, no residue

• Overnight fast 12 hours – water only

• Test period 4 hours (3 hours of sample collection)1. Arise one hour prior to testing

• No smoking or vigorous exercise

2. Baseline breath sample3. Consume test substrate4. Repeat breath collections at 20 min intervals (15 mins for glucose challenge)

• RECORD SYMPTOMS including gas/bowel movements during testing

ONE DAY• ALLOWED: eggs, fish, chicken/meat, white rice, white rice

noodles, white bread (milk-free: a good quality sourdough is best), clear meat broth (NOT bone broth). Salt, pepper, oil/butter for cooking. Small amount of hard cheese for flavour. Black tea, coffee, herb tea (not liquorice)

• STOP all non-essential medication• NO: fruit, veges, wholegrains, legumes, nuts, seeds, milk,

processed meat,

Prep Diet Guidelines

What’s in the Test Kit:

Pre-paid bag (CourierPost) to send samples to

the lab.

Diet instructions & Client forms – to

send in with sample.

Laxative Herbal Tea (Alpine tea)ONLY for those with constipation, who did not have a bowel

motion the day before the prep diet.

Lactulose (15ml)

Breath collection device

10 test-tubesBubble bags to pack test tubes

in for sending to the lab.

Cardboard box to protect samples

10 labels

The Collection DeviceBREATHE into this end –

lips sealed around outside

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1.BREATHE until this bag is full….2

Test tube in “ready” position.

Continue breathing OUT. Push test tube fully onto the needle.

Count to 3. Remove. Label.

Repeat every 20 mins

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Rubber-covered needle

The SiBO Breath Test

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1. Test sugar consumed after collecting baseline sample

2. If present, SI bacteria ferment the sugar, producing

hydrogen and/or methane gas

3. Gases are absorbed into the blood stream and transported to

the lungs

4. Hydrogen, methane & carbon dioxide are

measured in the breath

• Medication restrictions/washout periods after antibiotics, unusual diarrhoea

• Prep period 24-48 hours• Restricted diet

• low residue = low fermentable

• Overnight fast (water only)

How Samples are Analysed

• 8-day window for sample analysis

• Samples extracted by the Alveolac

• Quintron Breath Tracker • Uses gas chromatography

• Gold standard in breath testing

• Evaluates• Methane

• Hydrogen

• Carbon dioxide

• Corrects automatically based on CO2 content

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Interpreting Results• First principle

• ONLY bacteria produce these gases

• Second principle• Elevated baselines considered abnormal

• As long as prep diet was adhered to

• Third principle• Increases after 100 minutes most likely indicate

colonic fermentation

• Fourth principle• The rise in gas or gases must be significant

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Interpreting Results

33Am J Gastroenterol 2017; 112:775–784

Interpreting Results• Various criteria in the literature

• Currently – Diagnosis based on what happens in the first 90 minutes • Hydrogen

• Rise of 20 ppm (c.f. lowest preceding value)

• Methane• Any methane at or above 10 • A rise of 12ppm (c.f. lowest preceding value)

• Combined• Rise of 15 ppm in methane + hydrogen

EXPECT: Double peak (but not required) – aids understanding of localityEXPECT: A rise after 100-120mins (colonic fermentation)

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An (almost) Normal

Breath Test

• Slightly elevated baselines

• No significant change until after 100mins

• Good colonic increase• NB symptoms:

• ? Lactose intolerance

Looks normal but is missing a significant colonic rise

• Reasonable baselines

• Flatline until 3 hour mark

• Moderate increase only

• “The expected colonic rise is late and less than expected”

• Abnormal test.

DISTAL SIBO• Low baselines

• Flatline for 40mins = duodenum and proximal jejunum are intact

• Large increase +57ppm H2 & + 13ppm CH4 at 60 mins

• Sustained rise

• FALLS in the colon

• DISTAL SIBO

Elevated baseline,

invalid sample

?FLATLINE

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Missing data – not enough CO2 in test tube

IMP: Gases produced in colon were passed (sample #1)• Absent colonic rise. • ? Hydrogen-sulphide (evaluate food sensitivities/stool/gas odour), OR• Inadequate colonic flora

POSITIVE SIBO• Elevated baseline – esp

CH4

• Significant increase CH4 + H2 at 40 mins (+39ppm)

• Increases continue to peak at 100mins

• Significant symptoms during testing

• Abnormal test – Mixed gas SIBO

Invalid Sample

“Not enough CO2 in the test tube”

© 2018 Sharon Erdrich

Methane-Positive SIBO• NB: consensus document did not specify methane

increase for bacterial overgrowth (just that 10ppm or more was abnormal)

• Note:

• immediate increase +45ppm CH4 within 20 mins of consumption of lactulose.

• + 45ppm CH4 from 20 – 40 mins

• Decrease, then +24ppm CH4 between samples 3 & 4

• Flat-line hydrogen (H2 used by methanogenic bacteria)

C + H2 + H2 = CH4

• THIS CASE: Proximal SiBO & Distal SiBO

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Glucose challenge note the decrease in gases as the substrate is absorbed

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• Testing at 15-minute intervals

• Extremely elevated baselines

• Big drop after swallowing (?oral flora)

• Calculate from LOWEST value (@15mins)

• Combined gases = 46

• 60 mins total H2 + CH4 = 63

• Increase = +17ppm

• POSITIVE

Hydrogen-positive, Distal SIBO43

• BO 3 x day

• BSC #6-7

• Note the presumed transit at sample #7

Successful Treatment

• Same client – positive SIBO at 20 mins (severe histadelia)

• Very high methane

• Note the resizing of the graph

• Successful treatment of proximal SiBO & reduction of methane levels

• Absent colonic rise

Read the data, not the graph

For an more in-depth understanding of SiBO, visit the education portal –you can download the full seminar. Join our closed facebook group for practitioners only “NZ Clinicians for

Gut Health”