Symptoms and Complications of Crohn's Disease - Symptoms: abdominal pain, diarrhea (including bloody diarrhea), fever, weight loss, abdominal distension - Complications: anemia, skin rashes (infections, pyoderma gangrenosum, erythema nodosum), arthritis, inflammation of the eye, fatigue - Extraintestinal complications: ulcerative colitis, nutrient deficiency, higher risk of colon cancer, iritis/uveitis, primary sclerosing cholangitis, ankylosing spondylitis, pyoderma gangrenosum, erythema nodosum

Causes and Risk Factors of Crohn's Disease - Combination of environmental, immune, and bacterial factors - Genetic susceptibility (more than 70 genes involved) - Increased risk for smokers - Possible association with gastroenteritis - Similar symptoms to irritable bowel syndrome and Behçet's disease

Treatment and Management of Crohn's Disease - No known cure - Symptom management and maintenance of remission - Corticosteroids for short-term improvement - Medications like methotrexate or thiopurine for prevention of recurrence - Smoking cessation recommended

Epidemiology and Impact of Crohn's Disease - Prevalence of 3.2 per 1,000 people in Europe and North America - Less common in Asia and Africa - Increasing rates in the developing world since the 1970s - 47,400 deaths in 2015 due to inflammatory bowel disease - Slightly reduced life expectancy for individuals with Crohn's disease

Manifestations and Complications of Crohn's Disease in Various Organ Systems - Extraintestinal manifestations: visual manifestations (uveitis, conjunctivitis, etc.), gallbladder and liver involvement (increased risk of gallstones, primary sclerosing cholangitis, etc.), renal and urological manifestations (nephrolithiasis, obstructive uropathy, etc.), pancreatic, cardiovascular, respiratory, musculoskeletal, and dermatological manifestations - Intestinal damage: obstruction, fistulae, abscesses, intestinal stenosis, intestinal granulomas - Increased risk of cancer: small intestinal cancer, colon cancer - Major complications: bowel obstruction, abscesses, free perforation, hemorrhage, malnutrition, need for oral supplements or total parenteral nutrition - Dermatological manifestations: erythema nodosum, pyoderma gangrenosum, clubbing deformity of the fingers, psoriasis, rare manifestations - Neurological and psychological complications: seizures, stroke, myopathy, peripheral neuropathy, headache, depression, convulsions, meningitis, association with psychological disorders and poor self-image

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