Definition
Crohn's disease is a chronic, segmental inflammation of the gastrointestinal tract. It may involve either or both the small and large intestine, yet the majority of cases involve the terminal ileum. Clinical presentation and numerous possible complications correlate with anatomic location. In the general population, about 6 to 7 per 100,000 people acquire Crohn's disease yearly.
Etiology
The etiology of Crohn's is unknown. Various hypotheses include autoimmune, microbial pathogen, virus, and abnormal immune response theories.
Risk Factors
* Age peak incidence at 15 to 25 and 55 to 65 years of age
* Jews (three to eight times more common than general population)
* Caucasians > blacks, but gap is narrowing
* Females, slightly
* Genetic tendency
* Smokers
Signs and Symptoms
* Diarrhea
* Abdominal pain, distention
* Fatigue
* Weight loss, malnutrition
* Fever
Possible symptoms:
* Diarrhea
* Bleeding
* Perianal involvement
* Fistulae
* Vomiting, nausea
* Megacolon
Extraintestinal symptoms:
* Colitic arthritis
* Ankylosing spondylitis
* Urinary tract infections, occlusions
* Uveitis, episcleritis, thrombosis
* Hepatitis, cirrhosis, fatty liver, pericholangitis
* Gallstones, sclerosing cholangitis
* Erythema nodosum, pyoderma gangrenosum
* Kidney stones
* Renal amyloidosis
Differential Diagnosis
* Ulcerative colitis
* Beh?et's syndrome
* Appendicitis
* Irritable bowel syndrome
* Ileitis
* Amebiasis
* Diverticulitis
* Hemorrhoids, anal fissures
Diagnosis
Physical Examination
The patient appears weak, showing signs of malnutrition. The abdomen may be tender or distended on palpation. Auscultation reveals hyperactive bowel. Fistulas may be apparent.
Laboratory Tests
* Blood work may show anemia, thrombocytosis, decreased hematocrit, increased orosomucoid levels, elevated leukocyte count (sometimes indicating abscess), malnutrition
* Elevated erythrocyte sedimentation rate especially in colonic disease
* Hypoalbuminemia indicates severity and malnutrition
* B12 and folate deficiency
Pathology/Pathophysiology
* Inflammation
* Transmural (extending from mucosa to serosa through bowel wall)
* With fibrosis, leads to obstruction, strictures, intestinal wall thickening, lumen narrowing
* Transmural inflammation forms transmural fissures
* Mesentery edematous and thickened
* Cobblestoning aphthoid ulcers enlarge and connect to form stellate and linear ulcers, producing a nodular appearance as ulcers are separated by areas of normal mucosa
* Fistulas develop from base of aphthoid ulcers
* Abscesses crypt abscesses with neutrophil infiltrate
* Decreased size of bile salt pool from extensive ileal resection results in fat malabsorption
* Polymorphonuclear cells in surface epithelium
* Granulomas in submucosa, liver, lymph nodes, peritoneum, mesentery
* Axonal necrosis of autonomic nerves
Imaging
* Computed tomography shows abscesses, perforations, bowel wall thickening, perianal disease
* Barium X rays show lesions, strictures, ulcers, fistulae, narrowed lumen; side effect barium enema may induce toxic megacolon in some colitis cases
* Single contrast radiography shows colonic dilation with toxic megacolon
* Ultrasound shows abscesses (used for percutaneous drainage procedures), bowel wall thickening
* Fluoroscopy shows thickening of mesentery, bowel wall
Other Diagnostic Procedures
No single finding is diagnostic. Diagnosis is based on history, laboratory, clinical, and endoscopic findings.
* Proctoscopy if abnormal, rules out irritable bowel syndrome; may reveal aphthoid ulcers
* Colonoscopy shows extent of mucosal disease, lesions, strictures, ulcers; biopsies taken may reveal granulomas, inflammation
Treatment Options
Treatment Strategy
Although some treatments delay recurrence, all treatments, including surgery, are strictly palliative.
Drug Therapies
Corticosteroids prevents/suppresses inflammation; first rule out abscesses, can cause sepsis; ineffective maintenance therapy; side effects, osteoporosis and cataract formation; dose reduced by concurrent immunosuppressive and antidiarrheal drugs.
* Prednisone 20 to 40 mg/day for 10 to 14 days, taper by 5 mg every 7 to 10 days after four to six weeks or maintain at 5 to 10 mg/day for chronic activity; one- to three-week response time
* Parenteral corticosteroids for severe symptoms
Sulfasalazine 500 mg bid increasing to 3 to 4 g/day if tolerated, take with folic acid 1 mg/day; mainstay for colonic involvement; three- to four-week response time; side effects dyspepsia, nausea, neutropenia, hemolysis, may be controlled with lower dose; active agent is 5-ASA.
* Oral 5-ASA (e.g., mesalamine up to 4.8 mg/day), three- to four-week response time; prolongs remission; well tolerated
* Enema or suppository 5-ASA (e.g., mesalamine); six-week response time
Immunosuppressives block lymphocyte activation, proliferation, and effector mechanisms; for patients refractory to other treatments.
* 6-mercaptopurine or azathioprine begin at 50 mg/day, increasing to 2 mg/kg/day if tolerated; three-month response time; with ileal resection; side effects leukopenia, hepatitis, pancreatitis, rash
* Methotrexate 25 mg/week intramuscularly for three months then change to oral and taper, take with folic acid 1 mg/day; side effects leukopenia, pneumonitis, liver abnormalities, requiring liver biopsy after 1,500 mg total dose
* Cyclosporine 5 to 7.5 mg/kg/day; few days response time but frequent renal toxicity
Antidiarrheal drugs loperamide and diphenoxylate; cholestyramine (4 g/day or bid ) and a low-fat diet for ileal resection; risk of toxic megacolon with severe disease; limit addictive agents; bran and psyllium good stabilizers
Broad-spectrum antibiotic therapy for abscesses, colitis, ileocolitis, ileal resection, perianal disease (e.g., metronidazole 10 mg/kg/day); two- to four-week response time; side effects include nausea, anorexia, paresthesias (reversible, dose dependent); six-month use may prolong remission.
Psychotropic agents and support groups for psychosocial pressures.
Surgical Procedures
Indicated in 70% of patients; for abscesses, fistula, obstruction, toxic megacolon, recurrent hemorrhaging, and failure of medical management; not curative. Repeated surgeries may be required, with possible consequence of short bowel syndrome.
Complementary and Alternative Therapies
Although the etiology of Crohn's disease is not understood, nutritional support and herbal therapies can be very effective at minimizing the sequelae of malabsorption as well as possibly facilitating the healing of gut mucosa. Specifically, nutrition and herbs can enhance the integrity of the intestinal mucosa by possibly restoring the mucosal barrier and reducing intestinal permeability. Homeopathy may be helpful in acute cases. Mind-body therapies, such as meditation, yoga, and tai chi may help reduce the frequency and severity of exacerbations.
Nutrition
* Eliminate all known allergens in addition to highly allergenic foods linked to Crohn's disease, specifically, wheat, corn, and dairy. Eliminate pro-inflammatory foods and saturated fats such as caffeine (including chocolate), animal products, sugar, and alcohol.
* Consider an elimination/challenge or a five-day rotation diet.
* Increase fiber and omega-3 oils (e.g., flaxseed oil, 1 tbsp./day).
* Normalize gut microflora with supplementation of acidophilus (one capsule with meals).
* Replace vitamins and minerals associated with malabsorption syndromes: A (50,000 IU/day), E (400 to 600 IU/day), B12 (1,200 mcg/day), folate (800 mcg, 1,200 mcg/day with sulfasalazine use), C (1,000 mg tid), calcium (1,000 mg/day), magnesium (400 mg/day), zinc (30 to 40 mg/day), selenium (200 mcg/day).
* Eliminate refined, processed products that may compromise gut mucosa.
Herbs
Herbs may be used as dried extracts (pills, capsules, or tablets), teas, or tinctures (alcohol extraction, unless otherwise noted). Dose for teas is 1 heaping teaspoon herb/cup water steeped for 10 minutes (roots need 20 minutes).
* Robert's Formula is a traditional herbal blend that may help to soothe intestinal tissues, restore the integrity of the intestinal barrier, and reduce inflammation. Robert's Formula: marshmallow root (Althaea officinalis), wild indigo (Baptisia tinctoria), coneflower (Echinacea purpurea), geranium (Geranium maculatum), goldenseal (Hydrastis canadensis), poke root (Phytolacca americana), comfrey (Symphytum officinale), slippery elm (Ulmus fulva), cabbage powder, pancreatin, and niacinamide. Two capsules bid to qid.
* Flavonoids can help reduce inflammation and minimize reactions to food sensitivities. Quercetin (500 mg) before meals.
* Marshmallow tea (1 qt. daily) is soothing. Make a cold-water extraction by soaking 1 heaping tablespoon of root in 1 quart of cold water overnight. Drink throughout the day.
Homeopathy
An experienced homeopath would consider an individual's constitutional type to prescribe a more specific remedy and potency. Some of the most common acute remedies are listed below. Acute dose is three to five pellets of 12X to 30C every one to four hours until symptoms resolve.
* Aloe for gushing diarrhea with clumps of mucus; sense of weakness and venous congestion in the anus
* China officinalis for diarrhea with bloating and rumbling ameliorated by hard pressure
* Podophyllum for explosive, foul, watery diarrhea that may be yellow, pasty, mucus-filled, or bloody
* Mercurius vivus for offensive stools accompanied by a sensation of fullness
Acupuncture
May help normalize digestive function
Massage
May help relieve stress
Patient Monitoring
Closely monitor patients during periods of active disease. Counseling and support may be necessary due to long duration of active disease and chronicity.
Other Considerations
Complications/Sequelae
* Obstruction from adhesions, scarring, mucosal thickening, muscular hyperplasia
* Abscesses 15% to 20% of patients; occur in terminal ileum, liver, spleen, site of anastomosis
* Fistulas 20% to 40% of patients; commonly enteroenteric or enterocutaneous; usually involves terminal ileum
* Colon cancer with colonic Crohn's only; younger onset, higher incidence than general population, increases with duration
* Perianal disease ulcers, abscesses, fistulas; may destroy anal sphincter
Prognosis
* Within 10 years of diagnosis, 60% to 70% of patients have surgery, with a 70% rate of recurrence at one year
* Periods of remission
Pregnancy
* Spontaneous abortion slightly higher (12.2% versus 9.9%); premature births and defects similar to general population
* Corticosteroids and sulfasalazine considered relatively safe
* Sulfasalazine causes reversible male sterility
* Immunosuppressive drugs are teratogenic
* Inactive Crohn's disease at conception usually remains inactive
References
Dambro MR. Griffith's 5-Minute Clinical Consult. 1999 ed. Baltimore, Md: Lippincott Williams & Wilkins, Inc.; 1999.
Fauci AS, Braunwald E, Isselbacher KJ, et al, eds. Harrison' s Principles of Internal Medicine. 14th ed. New York, NY: McGraw-Hill; 1998.
Morrison, R. Desktop Guide to Keynotes and Confirmatory Symptoms. Albany, Calif: Hahnemann Clinic Publishing; 1993:15, 121, 305.
Murray MT, Pizzorno JE. Encyclopedia of Natural Medicine. 2nd ed. Rocklin, Calif: Prima Publishing; 1998:243, 250.
Rakel RE, ed. Conn's Current Therapy. 50th ed. Philadelphia, Pa: W.B. Saunders; 1998.
Washington Manual of Medical Therapeutics. 29th ed. Philadelphia, Pa: Lippincott-Raven Publishers, 1998.
Werbach M. Nutritional Influences on Illness. New Canaan, Conn: Keats Publishing Inc; 1987: 142-148.
Yamada T. Textbook of Gastroenterology. 2nd ed. Philadelphia, Pa: Lippincott-Raven Publishers; 1995.







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