Jay Yepuri, MD, MS, is a board-certified gastroenterologist and a practicing partner at Digestive Health Associates of Texas (DHAT).
Crohn’s disease is an inflammatory bowel disease caused by inflammation in the gastrointestinal (GI) tract. It's characterized by abdominal pain, cramps, bloody stool, diarrhea, and/or weight loss.
The diagnosis is complex, and involves clinical history, lab tests, imaging, and endoscopy (a camera inserted into the mouth) or colonoscopy (a camera inserted into the anus).
Dietary strategies, such as getting enough fluid and fiber and maintaining a nutrient- and calorie-rich diet, are cornerstones of symptom control. Medications like Asacol (mesalamine), methotrexate, or Humira (adalimumab) may reduce inflammation, and infections are treated with antibiotics. Surgery may be necessary for complications like anal fissures and bowel obstruction.
Crohn's disease is caused by patchy areas of inflammation and deep ulcers in the GI tract. The lesions can affect one or more sections of the GI tract, appearing anywhere between the mouth and the anus and causing irritation of the tissue. These issues interfere with digestion of food and lead to the symptoms and complications of Crohn’s disease.
Hereditary and environmental issues are associated with Crohn’s disease, and sometimes it occurs without risk factors. Risk factors include family history, smoking, urban living, and bacterial overgrowth. Experts believe that a weak immune system or an overactive immune system could be at play. Certain medications, including antibiotics and NSAIDs, may contribute to the condition as well.
Crohn’s disease is diagnosed with several criteria, and direct visualization of the lesions is the most definitive. Endoscopy or colonoscopy may identify a cobblestone-like appearance of the lesions. Weight loss, ulcerations on imaging tests, or inflammatory blood test markers (like erythrocyte sedimentation rate), can support the diagnosis and help determine its severity and prognosis.
There is a familial predisposition to Crohn’s disease, and experts suggest that there could be a genetic component, as well as environmental factors that contribute to this condition. There is no clear hereditary pattern of Crohn’s disease inheritance, and there is no specific gene identified as responsible for the condition.
An anal fissure is a cut in the inner lining of the anus. It can cause sharp pain and bleeding when passing stool. Anal fissures may form as a result of injury from passing hard stools. They often heal with home remedies, such as eating more fiber, medication for softening stool, and sitz baths. But they can become infected and may require medical or surgical intervention.
Bowel obstruction occurs when the small or large intestine becomes partially or completely blocked. Severe constipation is a sign of bowel obstruction, and it may lead to intestinal infection, bleeding, or perforation (a hole). It can occur due to blockage of the lumen (opening) or compression of the intestines and can be caused by inflammation, infection, cancer, and/or partially digested food.
A fistula is an abnormal tunnel-like structure that connects regions of the body that should not normally be connected to each other. GI fistulas can form in IBD, especially in the colon or anus. Fistulas can become infected and may need to be surgically repaired.
IBD includes Crohn’s disease and ulcerative colitis (UC). Both are chronic inflammatory GI conditions characterized by abdominal discomfort and may result in complications like bowel obstruction. While Crohn’s disease can involve any part of the GI tract, UC only involves the colon. And the lesions are superficial with UC, but they are deep with Crohn’s disease.
Malnutrition is inadequate nutrient absorption. Carbohydrates, proteins, and fats provide calories and essential dietary components. Vitamins and minerals provide nutrients to the body. A deficiency can occur due to dietary or GI issues like IBD. Malnutrition leads to growth problems in childhood, weight loss, fatigue, deficiencies in healing and immunity, and a variety of systemic diseases.
The small intestine is a long (20 to 25 feet ), muscular, coiled, tubular structure that produces digestive enzymes and absorbs nutrients. Partially digested food from the stomach enters the duodenum (first part of the small intestine) and is pushed by intestinal muscle contractions through the jejunum and ileum. Waste leaves the small intestine through the ileum to the colon (large intestine).
An ulcer forms when an organ’s protective lining is damaged and doesn’t heal. Ulcers can affect any part of the body, most commonly the skin and GI tract. GI ulcers can develop due to reflux (backflow of digestive fluid), medications (especially NSAIDs), or IBD. Ulcers can cause pain or bleeding, and they can become infected. They can also increase the risk of cancer.
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