Irritable Bowel Syndrome

By Tara NowakhtarDidacticsOnline.com

Case Presentation

24 year old female presents with the following symptoms Crampy feeling (abdominal pain),

varying intensity, intermittent Stress and eating exacerbate pain Bowel movement relieves pain Alternating diarrhea &

constipation Bloated/gassy feeling Gastroesophageal reflux (“heart

burn”) Dyspareunia, fatigue

Case:

Pt has had these symptoms for several days a month in the last 6 months

PMHx: depression, anxiety SHx: appendectomy PE:

Abdomen tender to palpation in all 4 quadrants with significant guarding

Abdomen sounds tympanic on percussion Global fascial tightness throughout abdomen Paraspinal changes at T9-T10

Epidemiology of IBS

IBS is an intrinsic colonic motility disorder with several plausible causes: loss of tolerance to GI flora, genetic factors, environmental triggers

MC functional bowel disorder F>>M Risk factors:

Hx of childhood sexual abuse Domestic abuse in women Increased stress, depression, anxiety

Pathophysiology of IBS

No pathognomonic pattern of gut dysmotility can be identified with IBS, unlike other functional gut disorders; however, it is suggested that a motility disturbance is the underlying issue in IBS patients

Increased sensitivity in the viscera is commonly found in IBS patients Distention - Awareness and pain caused by balloon

distention in intestine are experienced at lower volume than with controls

Bloating – studies have shown that although there are similar amounts of gas in IBS vs. control patients, there is impaired transit of that intestinal gas

Pathophys….

Intestinal Inflammation – mucosal immune activation has been shown in IBS, characterized by alterations in immune cells and markers ; mostly in diarrhea predominant

Lymphocytes – increased numbers reported in colon and SI in he myenteric plexus

Mast cells – in terminal ileum, jejunum, colon; some studies have showed a correlation between abdominal pain and the presence of activated mast cells around colonic nerves

Pathophys….

Postinfectious IBS – this has been suspected based upon a history of acute diarrheal illness preceding onset of IBS symptoms in some patients

Signs & Symptoms

GI symptoms: Chronic abdominal pain (crampy, variable

intensity)▪ Emotional stress and eating pain, defecation

pain Altered bowel habits Other GI symptoms:▪ GE reflux, dysphagia, early satiety, dyspepsia,

nausea, non cardiac chest pain, abdominal bloating, increased gas (accompanied by flatulence or belching)

Non GI symptoms: Impaired sexual function, dysmenorrhea,

dyspareunia, increased urinary frequency/urgency

Altered Bowel Habits in IBS

Diarrhea Frequent loose stools of small volume, with

mucus Generally in the morning or after meals May be preceded by lower abdominal

cramps and urgency May have feeling of incomplete evacuation

Constipation Days to months; may include bouts of

diarrhea or normal bowel function Stools often hard and pellet shaped May sense incomplete evacuation even with

empty rectum

Diagnostic Criteria

There are no biologic disease markers for IBS, so diagnosis has been standardized with symptom based criteria

Manning Criteria – 1978, not used as much anymore

Rome Criteria – 1992, revised 2005, defined as recurrent abdominal pain/discomfort associated with altered defecation

Rome Criteria

Recurrent abdominal pain/discomfort at least 3 days per month in the last 3 months associated with 2 or more of the following: Improvement with defecation Onset associated with change in

frequency of stool Onset associated with change in form of

stool (appearance)

Subtypes

IBS with constipation (hard/lumpy stools predominant)

IBS with diarrhea (loose/watery stools predominant)

Mixed IBS (neither predominates)

Unsubtyped IBS (insufficient stool abnormality to meet the above subtypes)

Noncompatible symptoms Pain associated with: anorexia,

malnutrition, weight loss – these are rare with IBS unless there is severe psychologic illness

Progressive pain Pain that prevents sleep or wakes patient

from sleep Rectal bleeding Lab abnormalities: anemia, inflammatory

markers, electrolyte disturbances These are “alarm” symptoms and require

additional testing!

Keep in mind: IBS can look like other illnesses, and other illnesses can look like IBS!

Treatment of IBS

Dietary modification: pt may have food allergies, should exclude gas-producing foods, coffee, fatty foods, carbohydrates (sx may be related to impaired absorption of carbohydrates: FODMAPs enter distal small bowel and colon when they are fermented, leading to sx and increased intestinal permeability, although there have been few studies to demonstrate this); Increase fiber intake (say most studies, although keep in mind that might be an issue for diarrhea-predominant IBS)

Treatment (continued…)

Patient-physician relationship is important! Physical activity: in a randomized trial, this

was examined - Physical activity comprised of 20-6- min of moderate to vigorous activity 3-5x/w – showed improvement in severity of IBS compared with control group

Psychosocial therapies: behavioral treatments for those who associate sx with stressors – the goal being to reduce anxiety, among other things

Pharmacologic treatment of IBS

**these are to be used as an ADJUNCT to tx**AntispasmodicsAntidepressantsAntidiarrheal

agentsBenzodiazepines5-HT 3 receptor

antagonists

5-HT 4 receptor agonists

LubiprostoneGuanylate cyclase

agonistsMast cell stabilizersAntibiotics

Antispasmodics

Ex: hyoscine, cimetropium, pinaverium (short term relief, LT efficacy has yet to be demonstrated).

Can directly affect intestinal smooth muscle relaxation, or via anticholinergic/antimuscarinic properties

They reduce colonic motor activity and may improve postprandial abdominal pain, gas, bloating, and fecal urgency.

Antidepressants

Independent of their mood improving effects, antidepressants have analgesic properties, and therefore may be beneficial in patients with neuropathic pain

The assumed MOA with TCA’s and SSRI’s are facilitation of endogenous endorphin release, blockade of NE reuptake (leading to enhancement of descending inhibitory pain pathways), and blockade of the pain neuromodulator (5-HT). TCA’s also slow down intestinal transit time via anticholinergic properties (helpful in diarrhea predominant IBS)

Antibiotics

Some patients show improvement in sx’s of bloating, abdominal pain or altered bowel habits after use of antibiotics

Rifaximin, a nonabsorbable antibiotic, globally improved IBS symptoms in reports of two randomized trials

MOA is unclear, may be due to suppression of gas producing bacteria in the colon

CONS: Usually, pt has to pay out of pocket due to the outrageous cost of this medication

From the Osteopathic POV… In a 2007 article in Journal of Gastroenterology &

Hepatology titled “Treatment of Irritable bowel syndrome with osteopathy: Results of a Randomized controlled pilot study”, it was found that 13 of 19 patients in the group receiving osteopathic treatment had overall improvement of symptoms in 6 months, one was free of symptoms, and the remaining five showed slight improvement

In the standard care group, 3/17 subjects noted “definite” improvement, while 10 showed slight improvement. The remaining 3 had worsened sx’s

Improvement was statistically significant in favor of the osteopathic treatment group with a p value <0.006

OMT can be used!

MFR of abdominal fascia OA decompression ANS treatments Treatment of diaphragms (especially

thoraco-abdominal!) Treat the whole patient! Listen to the

patient, make sure to get a good hx: remember, these patients have had it with doctors and are trying to understand their illness, do your best to help them!

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