- Functional bowel disorder
- Intermittent or chronic abdominal pain
-changes in bowel habits
Epidemiology
- 10-15% of the Western World
-Likely underdiagnosed
onset - young adulthood
Associated conditions
- Fibromyalgia
-Chronic fatigue syndrome
-GERD
-MDD ( major depressive disorder )
-Anxiety
-Somatisation
Etiology
- Unknown ( no organic cause, functional bowel disorder )
- Gastrointestinal Motility disturbances
-Visceral hypersensitivity and altered perception
-psychiatric symptoms can precede the onset of GI symptoms
Other factors
- intestinal inflammation ( increased lymphocytes and mast cells )
- Fecal microbiome disruption ( bacterial overgrowth )
-Food sensitivity
-Post-infectious ( E. coli ( O157:H7 ), Campylobacter )
Signs and symptoms
- Abdominal pain ( associated with defection, cramping pain, exacerbated by meals and
stress
- Change in stool frequency and consistency ( Diarhhea and constipation )
diarrhea - in the morning and after eating
constipation - pellet shaped, can also have the sensation of tenesmus
other associated symptoms
-straining, urgency, tenesmus
-passage of mucous
-bloating and abdominal distension
Diagnosis
- Bowel habit journal
Rome IV criteria
- Symptoms one day per week in the past three months
-Abdominal discomfort
pain - associated with at least two
a. relieved /related with defecation
b.change in stool frequency
c.change in stool consistency
other symptoms
- change in frequency - more than 3 times per day ( diarrhea type ) or less than 3 times a week
- change in consistency - more than 1/4 of bowel movements
- change in sensation ( urgency or tenesmus ) - more than 1/4 of bowel movements
- passage of mucous - more than 1/4 of bowel movements
- sensation of bloating
Rule out red flag signs
- onset after 50 years
- anemia
- fever
-melena/hematochezia
-nocturnal defecation
-unexplained weight loss
-laboratory abnormalities
Rule out similar symptoms
- infections
-IBD
-Lactose intolerance
-celiac disease
-diet-induced diarrhea
-obstruction
-malignancy
IBS - Types
- IBS-D ( diarrhea type Bristol type - 6,7)
-IBS-C ( constipation type Bristol type - 1,2)
-IBS-M ( Mixed)
-IBS unclassified
IBS Management
- increase fiber intake ( 30gm/day)
-Low FODMAP diet
Fermentable oligo, Di, Monosachharied, and Polyols
-avoid gluten, lactose, and excess caffeine
-increase physical activity
-stress reduction
IBS with diarrhea
- loperamide
-cholestyramine
IBS with constipation
- Linaclotide
-Laxatives ( Lactulose, PEG )
Bloating and flatus
- alpha-galactosidase
-probiotics
-antibiotics
-simethicone
IBS related pain
- Tricyclic antidepressants
Rifaxamine if unresponsive
Other Therapies
- Relaxation therapy
- biofeedback
- probiotics
- hypnosis
Prognosis
- improve over time ( 80% )