Irritable bowel syndrome differential diagnosis

Irritable bowel syndrome Microchapters
Home
Patient Information
Overview
Historical Perspective
Classification
Pathophysiology
Causes
Differentiating Irritable bowel syndrome from other Diseases
Epidemiology and Demographics
Risk Factors
Screening
Natural History, Complications and Prognosis
Diagnosis
Diagnostic Criteria
Diagnostic Study of Choice
History and Symptoms
Physical Examination
Laboratory Findings
Electrocardiogram
X Ray
CT
MRI
Ultrasound
Other Imaging Findings
Other Diagnostic Studies
Treatment
Medical Therapy
Monitoring
Surgery
Primary Prevention
Secondary Prevention
Cost-Effectiveness of Therapy
Case Studies
Case #1
Irritable bowel syndrome differential diagnosis On the Web
Most recent articles
cited articles
Review articles
CME Programs
Powerpoint slides
Images
American Roentgen Ray Society Images of Irritable bowel syndrome differential diagnosis All Images X-rays Echo & Ultrasound CT Images MRI
Ongoing Trials at Clinical Trials.gov
US National Guidelines Clearinghouse
NICE Guidance
FDA on Irritable bowel syndrome differential diagnosis
CDC on Irritable bowel syndrome differential diagnosis
Irritable bowel syndrome differential diagnosis in the news
Blogs on Irritable bowel syndrome differential diagnosis
Directions to Hospitals Treating Irritable bowel syndrome
Risk calculators and risk factors for Irritable bowel syndrome differential diagnosis

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Please help WikiDoc by adding content here. It's easy! Click here to learn about editing.

Differentiating Irritable Bowel Syndrome from other Diseases

American Gastroenterological Association Guidelines for Diagnosis of IBS

The American Gastroenterological Association has published a set of guidelines for tests which physicians should perform prior to diagnosing irritable bowel syndrome. The following tests are meant to exclude other causes, such as infection and colon cancer.

1. History and physical examination
2. Diagnostic testing
   1. CBC
   2. Chemistry panel
   3. Sedimentation rate
   4. Stool for O & P
   5. Stool for occult blood
   6. Flexible sigmoidoscopy
   7. IF > 50, colonoscopy or barium enema and sigmoidoscopy
   8. For diarrhea predominant:
      1. Small bowel radiograph
      2. Lactose/dextrose H2 breathing test
   9. For constipation predominant:
      1. Fiber trial
   10. For pain predominant:
       1. Plain film of abdomen

Diseases with similar symptoms

• Celiac disease
• Diverticulitis
• Endometriosis
• Gallstones
• Gastroesophageal reflux disease (GERD)
• Inflammatory bowel disease
• Lactose intolerance
• Thyroid disease

The table below summarizes the findings that differentiate watery causes of chronic diarrhea

Cause			Osmotic gap		History	Physical exam	Gold standard	Treatment
			< 50 mOsm per kg	> 50 mOsm per kg*
Watery	Secretory	Crohns	+	-	Abdominal pain followed by diarrhea	Abdominal tenderness when palpated in severe disease Blood seen on rectal exam Fever Tachycardia Hypotension	Colonoscopy with biopsy	Topical mucosamine and corticosteroids are preferred Mesalamine and sulfasalazine are used for remission
		Hyperthyroidism	+	-	Excessive sweating Heat intolerance Increased bowel movements	Lump in the neck Proptosis Tremors Increased DTR	TSH with T3 and T4	Carbimazole and methimazole Beta blockers like propylthiouracil Iodine-131
		VIPoma	+	-	Watery diarrhea Dehydration (thirst, dry skin, dry mouth, tiredness, headaches, and dizziness) Lethargy, muscle weakness Nausea, vomiting Crampy abdominal pain Weight loss Flushing	Tachycardia Rash Facial flushing Abdominal distention Abdominal tenderness in the right upper abdominal quadrant	Elevated VIP levels Followed by imaging	Sandostatin or chemotherapy for malignant tumors Surgical removal of the tumor
	Osmotic	Lactose intolerance	-	+	Abdominal pain Bloating Diarrhea Flatulence	Abdominal tenderness	Intestinal biopsy	Avoidance of dietary lactose Substitution to maintain nutrient intake Regulation of calcium intake Use of enzyme lactase
		Celiac disease	-	+	May be asymptomatic Vague abdominal pain Diarrhea Weight loss Malabsorption / steatorrhea Bloatedness	Abdominal pain and cramping Abdominal distention Tetany Mouth ulcers Dermatitis herpetiformis Signs of the fat-soluble vitamins A, D, E, and K deficiency	IgA tissue transglutaminase Ab	Gluten-free diet
	Functional	Irritable bowel syndrome	-	-	Abdominal pain or discomfort recurring at least 3 days per month in the past 3 months and associated with 2 or more of the following: Improves with defecation Onset associated with change in frequency of stool Onset associated with change in appearance of stool 25% of bowel movements are loose stools History of straining is also common	Abdominal tenderness Hard stool in the rectal vault	Clinical diagnosis ROME III criteria Pharmacologic studies based criteria	High dietary fiber Osmotic laxatives such as polyethylene glycol, sorbitol, and lactulose Antispasmodic drugs (e.g. anticholinergics such as hyoscyamine or dicyclomine)

Irritable bowel syndrome must be differentiated from diseases that cause abdominal pain and chronic diarrhea. The table below summarizes the findings that differentiate watery causes of chronic diarrhea:

Cause	Osmotic gap		History	Physical exam	Gold standard for diagnosis
	< 50 mOsm per kg	> 50 mOsm per kg*
Zollinger-Ellison syndrome	+	-	Abdominal pain and diarrhea Dyspepsia Upper or Lower gastrointestinal bleeding	Abdominal tenderness Hematochezia Hematemesis Tachycardia Hypotension	Gastrin levels
Crohn's disease	+	-	Abdominal pain followed by diarrhea	Abdominal tenderness when palpated in severe disease Blood seen on rectal exam Fever Tachycardia Hypotension	Colonoscopy with biopsy
Hyperthyroidism	+	-	Excessive sweating Heat intolerance Increased bowel movements	Lump in the neck Proptosis Tremors Increased DTR	TSH with T3 and T4
VIPoma	+	-	Watery diarrhea Dehydration (thirst, dry skin, dry mouth, tiredness, headaches, and dizziness) Lethargy, muscle weakness Nausea, vomiting Cramping abdominal pain Weight loss Flushing	Tachycardia Rash Facial flushing Abdominal distention Abdominal tenderness in the right upper abdominal quadrant	Elevated VIP levels Followed by imaging
Lactose intolerance	-	+	Abdominal pain Bloating Diarrhea Flatulence	Abdominal tenderness	Intestinal biopsy
Celiac disease	-	+	May be asymptomatic Vague abdominal pain Diarrhea Weight loss Malabsorption/steatorrhea Bloatedness	Abdominal pain and cramping Abdominal distention Tetany Mouth ulcers Dermatitis herpetiformis Signs of the fat-soluble vitamins A, D, E, and K deficiency	IgA tissue transglutaminase Ab
Irritable bowel syndrome	-	-	Abdominal pain or discomfort recurring at least 3 days per month in the past 3 months and associated with 2 or more of the following: Improves with defecation Onset associated with change in frequency of stool Onset associated with change in appearance of stool 25% of bowel movements are loose stools History of straining is also common.	Abdominal tenderness Hard stool in the rectal vault	Clinical diagnosis ROME III criteria Pharmacologic studies based criteria