Transcript Irritable Bowel Syndrome Jones

FUNCTIONAL BOWEL
DISORDERS
CURRENT APPROACH TO
IRRITABLE BOWEL SYNDROME
INTRODUCTION:
Irritable Bowel Syndrome (IBS) is a
gastrointestinal disorder characterized
by chronic abdominal pain associated
with altered bowel habits in the
absence of any organic cause.
IBS
Prevalence is 10-15% in the USA
Second leading cause of work
absenteeism in the USA
2:1 Female to Male predominance in the
USA
Equally prevalent in India however.
CLINICAL FEATURES OF IBS
Abdominal pain is quite variable:
•Location
•Intensity
•Duration
Characteristic Features of IBS
Abdominal Pain:
• Pain that is improved when recumbent
• Pain that typically does not awaken
the patient from sleep
• Pain that changes location
• Pain that is improved or worsened by
passage of stool or gas
ALTERED BOWEL HABITS
Variable stools—pellet like, ribbon like,
malodorous
Urgency, straining at defecation,
difficulty with stool expulsion
Sensation of incomplete evacuation,
mucus
Chronic diarrhea, chronic constipation,
diarrhea alternating with constipation
Other complaints associated
with IBS:
GE Reflux
Early Satiety, dyspepsia, nausea
Abdominal Distention, flatulence,
belching
Non-cardiac chest pain
Other complaints associated
with IBS (continued)
Sexual dysfunction, dysmenorrheal,
dyspareunia
Urinary frequency
Hypertension, asthma, and
fibromyalgia
MANNING CRITERIA FOR IBS
 Pain relieved with defecation
 More frequent stools at onset of pain
 Looser stools at onset of pain
 Visible abdominal distention
 Passage of mucus
 Sensation of incomplete evacuation
The likelihood of IBS is proportional to the number
of Manning’s criteria that are present
ROME CRITERIA FOR IBS
In the absence of structural or metabolic
abnormalities, with at least 12 weeks or more—
which need not be consecutive, in the
preceeding 12 months—of abdominal pain with
two of three following features:
 Pain relieved with defecation, and/or
 Pain onset associated with change in stool
pattern, and/or
 Pain onset associated with change in stool form
or appearance
Rome criteria, symptoms that
cumulatively support diagnosis of
IBS
Abnormal stool frequency
Abnormal stool form
Straining, urgency or sense of incomplete
evacuation
Passage of mucus
Abdominal distention
Etiology of IBS:
?Motility Disorder
?Post Infectious Immune
Reaction
?Anxiety Disorder
?Visceral Hyperalgia
?Dietary Fiber Deficiency
General Principles of
Management of IBS
IBS is considered a chronic condition
with no known cure. The focus of
treatment should be on symptom relief
and in addressing the patient's concerns.
Exacerbating factors (such as
medications and diet), stress, or
psychiatric disorders should be identified
if possible.
General Principles in
Management of IBS(continued)
Therapeutic physician-patient
relationship
Dietary Modification
Antispasmotics
Benzodiazepines — Anxiolytic agents
Low dose Anti-Depressants
5-hydroxytryptamine (serotonin)
3 receptor antagonists
Alosetron (Lotronex)
Somewhat beneficial in diarrhea
predominant IBS, but women only
Two studies demonstrated significant
benefit—pain reduction of 41% versus
28% in comparison to placebo.
Response typically occurred first 4
weeks of therapy and was sustained.
Dose is 2 mg po BID
Alosetron (Lotronex)
(continued)
• Caution: Severe ischemic colitis was
reported in 84 patients to FDA within first
year of release, with 54 requiring hospital
admission, 11 required surgery and there
were two deaths.
• An additional 83 patients required
hospitalization for severe constipation, 34 of
whom required surgery, and there were also
two deaths.
5-hydroxytryptamine (serotonin)
4 receptor agonists
Tegaserod (Zelnorm/Zelmac)
 Beneficial in constipation predominant IBS
 Dose is 6 mg po BID
 Three clinical trials in almost 2,500 patients
with IBS reported control of pain, distention,
and constipation. However, margin of benefit
was low—just 5-10% symptom response over
placebo. Maximum benefit was noted early
phase of study suggesting possible
tachyphylaxis.
Adverse Effects of Tegaserod
 Generally well tolerated—higher incidence of
diarrhea (9% vs. 4% for placebo)
 Reports of small increased incidence of
cholecystectomy of uncertain significance.
 Not carcinogenic, teratogenic, or toxic to the
fetus in animal studies
 No significant drug interactions observed
Contraindications to Tegaserod
Severe renal impairment
Moderate or severe hepatic impairment
History of bowel obstruction
Symptomatic gallbladder disease/or
suspected sphincter of Oddi
dysfunction
?Abdominal adhesions
Known allergy to the drug or any of its
excipients
Summary of Evaluation and
Management of IBS
 IBS is defined by chronic abdominal pain and an
alteration in bowel habits
 Numerous other complaints are associated with IBS
 Stress and Anxiety may be provocative factors, but
not thought etiologic
 Alosteron should be used with caution in IBS due to
catastrophic side effects
 Tegaserod appears safe, but only marginally
effective, will not be a panacea
 No currently available and reliable treatment for
Intestinal Gas complaints
HORSE SENSE
Physicians can be classified as:
• “LUMPERS” or
• “SPLITTERS”
VARIABILITY IN PRESENTATION
OF ACUTE MYOCARDIAL
INFARCTION
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•
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Stroke
Pulmonary Edema
Syncope
Sudden Death
Severe Heartburn
Jaw, Neck Pain or Arm Pain
Tachycardia
Etc.
Variability in the Clinical Features of
Functional Bowel Disorders:
•
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Functional Abdominal Pain
Alteration in Bowel Habits/Urgency
Abdominal Distention
Flatulence/Borborygmi
Aerophagia
Upright Refluxers (Regurgitation)
Proctalgia Fugax
Sensation of Incomplete evacuation of
stools
Normal Bowel Habits
(Current Dogma)
In a study of two population samples,
AM Connell found that 99% of the
population passed between three stools
weekly to three stools daily. This finding
has impacted GI research for decades.
AM Connell, BMJ 1965, 2:1095
Expanded Criteria for Constipation
At least 12 weeks which need not be consecutive in the
preceeding 12 months of 2 or more:
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Straining in > ¼ defecations
Lumpy or hard stools > ¼ of defecations
Sensation of incomplete evacuation in > ¼ of stools
Sensation of anorectal obstruction in > ¼ of stools
Manual manuevers to facilitate > ¼ defecations
< 3 defecations per week
Loose stools are not present and insufficient criteria for
diagnosis of IBS
• (see Locke et al)
Basic Concepts in Managing
Functional Bowel Disorders:
• The goal is to achieve 1-4 large soft stools
daily with minimal odor
• Begin with small amount of soluble fiber,
preferably Methylcellulose BID (e.g. ½
TBSP)
• Consider beginning with an osmotic
laxative daily, adjust dose to achieve
stated above stated goal
Basic Concepts in Management
(continued)
• Gradually increase the soluble fiber dose—
BID or TID preferable
• Once excellent stools, continue the osmotic
laxative daily, but gradually reduce the dose
• If much distention, reduce the fiber dose,
and/or increase the osmotic laxative
• For difficult patients, consider glycerine
suppositories and/or tap water enemas as
often as daily if needed for symptom control
Case # 1
• RJ--12 yo straight A student presented with
severe, recurrent abdominal pain (RAPS) and
alternating diarrhea and constipation. Also
complained of incomplete stool evacuation.
• Initially patient required fleets enema for partial
symptom relief.
• Asymptomatic on 4 gm psyllium once daily
• Symptom relapse frequently occurs within 1-2
days if non-compliant with psyllium
• 6 year followup
Case # 2
• TC—38 yo man with 15 year history of severe
IBS, manifest by attacks of severe lower abd.
pain, diarrhea, distention, N/V requiring frequent
admissions, 3-4 in past one year. Symptoms
especially provoked by travel.
• Constipated when not having attacks
• Work up included multiple EGD’s,
colonoscopies, CT scans, SBFT study, small
bowel biopsy, EEG, gastric emptying study
CASE # 2 (continued)
• Prior appendectomy and cholecystectomy
without benefit
• Tried numerous medications, including
anti-spasmotics, metoclopramide,
omeprazole, SSRI’s, tranquilizers, Citrucel
and used prn miralax (PEG)
• Followed at local university medical center
by a world reknown IBS specialist
CASE # 2 (continued)
• Patient started on regimen of Citrucel (methyl
cellulose) BID, which was increased as tolerated
• He was instructed to take Miralax daily and to
adjust the dose to achieve excellent stools daily
• 2 admissions first 3 months after evaluation with
severe attack
• No further episodic attacks of pain or N/V—
subsequent 12 months symptom free
• Now on fiber cereals and Benefiber (guar gum),
and off Citrucel and Miralax
CASE # 3
• DG—49 yo woman presented in 1996 with
1 year h/o intractable GE Reflux/heartburn
• EGD was normal. Esophageal manometry
was c/w GE reflux. No 24 hr. pH study
• Stools were 3/week. No distention.
Psyllium worsened her complaints
• No response to PPI’s BID and cisapride
CASE # 3 (continued)
• A partial fundoplication (Toupee) did not control
her GE Reflux symptoms.
• Six months later, an open Nissen
fundoplication again, no symptom response
• In 1998, Citrucel BID plus milk of magnesia
PRN was initiated.
• Once excellent bowel habits achieved, all PPI’s
were stopped. Now uses ranitidine PRN only.
GOAL OF THERAPY FOR FIBER
SUPPLENTATION:
• Based upon 20 years of experience as a
gastroenterologist, the goal of my patients
is to achieve 2-4 large soft stools daily with
minimal odor.
• Stool volume should be 600 to 1,000 cc
daily of soft stools with minimal odor.
Note: patients < age 40 may find that 1-3
large soft stools may be satisfactory
Constipation and “not know it!”
Just as a patient can have a heart attack
without chest pain, or any other symptoms
for that matter, one be constipated and
“not know it.”
That is, one can have regular stools daily
and “still be constipated.” Foul smelling
stools are as indicative of constipation as
hard stools, or infrequent stools.
The Paradox Fiber and Increased
Abdominal Pain and Gas:
Once fiber is introduced, due to fact it is not
digested and thus can be fermented in the
large bowel, one should initially expect
some increase in functional abdominal
symptoms, until excellent bowel habits are
achieved—which explains the paradox of
why dietary fiber may initially exacerbate
functional bowel disorders.
Citrucel (methylcellulose) Causes
Less Gas Initially
Plastic is made from oil, and then basically
ground up to make Citrucel/Methylcellulose. Since people do not regularly
ingest oil or plastic for that matter, the
bacteria that colonize the colon cannot
ferment it very efficiently. However, after a
number of months, they begin to recognize
methylcellulose and can ferment it.
A Spastic Colon is like a Railroad
Car
20 or 30 men can get a railroad car rolling
on level tracks by using ropes and pulleys.
However, once the inertia of that heavy
railroad car is overcome, just 2 or 3 men
can keep it rolling down the tracks. The
colon is much like a heavy railroad car that
sits on the railroad track. Osmotic
laxatives or infrequently tap water enemas
may be required to overcome this inertia.
SUMMARY
In Summary, functional bowel disorders
include a large variety of unexplained
abdominal complaints. Dietary
intervention is successful in controlling
even the most difficult patients with IBS. I
usually begin with 0.5 gm of Citrucel BID
and increased as tolerated to 4 gm. BID.
Frequently patients require an osmotic
laxative, which should be taken initially on
a daily basis.
SUMMARY (continued)
• Once excellent bowel habits are achieved,
other forms of soluble dietary fiber is
encouraged. Due to the many years of a
low fiber diet and small volume stools,
significant resistance may be encountered
when fiber is first introduced. For this
reason, IBS symptoms may initially flare
as patients adapt to the dietary change.