Inflammatory Bowel Disease

Inflammation of the bowel caused by dysregulated or inappropriate immune response to environmental factors in a genetically susceptible host

Crohns Disease

• Involves any region of the GI tract (Mouth to Anus)
• Eccentric and segmental lesions with "skip" areas (normal bowel between two affected regions)
• Lesions are often transmural (UC lesions are limited to the mucosa)

Incidence / Prevalence

• Incidence = 4.56 / 100,000
• Prevalence = 43/100,000

Clinical Manifestations

• Fever, Malaise, Easy fatigability
• Growth Failure
• can be with delayed bone maturation or delayed sexual development 
  
• These may precede other symptoms by 1-2 years
• 2x as likely in Crohn than UC
  
• Growth Failure may be the only manifestation of disease
• Decreased height velocity occurs in 88% of prepubertal patients and often precedes GI Sx
• Primary or secondary amenorrhea and pubertal delay are common
• Causes of Growth Failure:
• inadequate caloric intake
• suboptimal absorption / malabsorption / excessive loss
• chronic inflammatory effect on bone metabolism and appetite
• use of steroids for treatment
• Perianal disease is common
• Tag
• Fistula
• Deep fissure
• Abscess
• Recurrent Vomiting and epigastric pain may indicate gastric or duodenal involvement
• Cramping abdominal pain, borborygmus, and intermittent gaseous distention can be caused by partial small bowel obstruction secondary to narrowing of bowel lumen from inflammation or stricture
• Stricture should be suspected if patient feels relief of symptoms associated with sudden sensation of gurgling of intestinal contents through a localized area of the abdomen
• Penetrating Disease is marked by fistula formation
• Enteroenteric or enterocolonic fistula
  
• typically asymtomatic but can contribute to malabsorption through high output or bacterial overgrowth
  
• Enterovesical fistula
• bowel to urinary bladder
• usually from ilium or sigmoid colon
• present with UTI, pneumaturia, fecaluria
  
• Enterovaginal fistula
• rectum to vaginal
• feculent vaginal drainage
• difficult to manage
  
• Enterocutaneous fistula
• bowel and abd skin
• prior surgical anastamosis with leakage
• Perianal fistula
  
• Usually associated with purulent drainage
• Complex - due to different tissue planes
• Abscess
• Intrabdominal abscess
• fever and pain otherwise few symptoms
  
• Hepatic or splenic abscesses
• can occur with or withour local fistula
  
• Anorectal abscess
• usually originate immediately above the anus and the crypts of morgagni
• 
  
• Perianal Abscess
• Painful
  
• Psoas Abscess
  
• if secondary to intestinal fistula, can present as hip pain, decrease hip extension (psoas sign), and fever

Extraintestinal Manifestations

• more common in crohn disease than UC
• appearance of these symptoms typically correlates with colitis
  
• Typical crohn manifestations include:
• oral aphthous ulcers
• peripheral arthritis - non-deforming
  
• erythema nodosum
• digital clubbing
• episcleritis
• renal stones (uric acid , oxalate)
• gallstones
  

DDx:

• most common diseases to be distinguished from IBD in the workup are:
• Infectious enteropathies
• Acute terminal ileitis
• infectious colitis
• enteric parasites
• periappendiceal abscess
• Yersinia can cause similar radiographic and endoscopic findings in the distal small bowel that are seen in crohn disease
• Celiac and Giardia can produce a crohn-like presentation with diarrhea, weight loss, and protein-losing enteropathy
• GI tuberculosis
• Foreign body perforation (tooth pick)
• Small bowel lymphoma
• associated with small nodular-filling defects of the bowel without ulceration or narrowing of the lumen
• much less common than crohn
• Recurrent functional abdominal pain
• lymphonodular hyperplasia of the terminal ileum may be mistaken for crohn ileitis
• RLQ pain or mass with fever can be the result of periappendiceal abscess, sometimes associated with diarrhea

Primary Presenting Symptoms	Potential causes
RLQ abd pain w/ or w/o mass	Appy Infection (campylobacter, Yersinia) Lymphoma Intussusception Mesenteric Adenitis Meckel Diverticulum Ovarian Cyst
Chronic periumbilical or epigastric abd pain	Irritable bowel syndrome Constipation Lactose intolerance Peptic disease
Rectal bleeding without diarrhea	Fissure Polyp Meckel Diverticulum Rectal ulcer syndrome
Bloody Diarrhea	Infection Hemolytic-uremic syndrome Henoch-Schonlien purpura Ischemic bowel Radiation Colitis
Watery Diarrhea	IBS Lactose inteolerance Giardiasis Cryptosporidium Sorbitol, olestera, or other food additive Laxatives
Perirectal disease	Fissure Hemorrhoid Streptococcal infection Condyloma
Growth delay	Endocrinopathy
Anorexia, wt loss	Eating Disorder e.g. Anorexia Nervosa
Arthritis	Collagen vascular disease Infection
Liver Abnormalities	Chronic Hepatitis

Dx

• At initial presentation
• 50% have disease of the ileum and colon (ileocolitis)
• 30% have Upper GI involvement
• 20% have exclusively colonic disease
• only 25% will have the triad of diarrhea, weight  loss, and abdominal pain
• 25% have GI bleeding
  
• Labs (tailored based on DDx)
  
• CBC
• ESR
• CRP
• CMP (Albumin, liver aminotransferases)
• Fecal Calprotectin
• Lactoferrin
• If alk phos is low, assess zinc status
• C Diff
• CMV
• Iron Panel (if Iron Deficiency suscpected)
• Procedures
• EGD/ Colonoscopy - non-specific inflammatory changes (erythema, friability, loss of vascular pattern), aphthous ulcers, linear ulcers, nodularity, and strictures
• noncaseating granulomas (similar to those found in sarcoidosis) are the most characteristic findings -but not often present
• transmural inflammation is only identified in surgical specimens
  
• Video Capsule Endoscopy - contraindicated if stricturing disease is present (use patency capsule to assess)
• Radiology
• Abd Plain films - may be normal or reveal small bowel obstruction (SBO) or thumbprinting of the colon wall
• Upper GI contrast study with small bowel follow through - aphthous ulceration or thickened nodular folds or narrowing/stricturing of the lumen
• linear ulcerations can give cobblestone appearance to mucosal surface
• bowel loops often seperated as result of thickening of bowel wall and mesentery
• Fistulas
• Sinus Tracts
• Strictures
• CT and Magnetic Resonance enterography (MRE) - can assess for extraintestinal manifestations like phlegmon and abscess
  
• Small Bowel ultrasound
• PET (or MR) can differentiate obstruction as inflammatory or fibrotic

Tx

• Five principal components of Treatment
• Medications
• Surgery
• Nutritional Rehabilitation
• Psychosocial Support
• Colorectal cancer screening for older patients
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