is useful when the disease involves only the small intestine. because colonoscopy and gastroscopy allow direct visualization of only the terminal ileum and beginning of the duodenum, they cannot be used to evaluate the remainder of the small intestine. as a result, a barium follow-through x-ray, wherein barium sulfate suspension is ingested and fluoroscopic images of the bowel are taken over time, is useful for looking for inflammation and narrowing of the small bowel. barium enemas, in which barium is inserted into the rectum and fluoroscopy is used to image the bowel, are rarely used in the work-up of crohn's disease due to the advent of colonoscopy. they remain useful for identifying anatomical abnormalities when strictures of the colon are too small for a colonoscope to pass through, or in the detection of colonic fistulae (in this case contrast should be performed with iodate substances). ct and mri scans are useful for evaluating the small bowel with enteroclysis protocols. they are also useful for looking for intra-abdominal complications of crohn's disease, such as abscesses, small bowel obstructions, or fistulae. magnetic resonance imaging (mri) is another option for imaging the small bowel as well as looking for complications, though it is more expensive and less readily available. mri techniques such as diffusion-weighted imaging and high-resolution imaging are more sensitive in detecting ulceration and inflammation compared to ct. blood tests a complete blood count may reveal anemia, which commonly is caused by blood loss leading to iron deficiency or by vitamin b12 deficiency, usually caused by ileal disease impairing vitamin b12 absorption. rarely autoimmune hemolysis may occur. ferritin levels help assess if iron deficiency is contributing to the anemia. erythrocyte sedimentation rate (esr) and c-reactive protein help assess the degree of inflammation, which is important as ferritin can also be raised in inflammation. serum iron, total iron binding capacity and transferrin saturation may be more easily interpreted in inflammation. anemia of chronic disease results in a normocytic anemia. other causes of anemia include medication used in treatment of inflammatory bowel disease, like azathioprine, which can lead to cytopenia, and sulfasalazine, which can also result in folate deficiency. testing for saccharomyces cerevisiae antibodies (asca) and antineutrophil cytoplasmic antibodies (anca) has been evaluated to identify inflammatory diseases of the intestine and to differentiate crohn's disease from ulcerative colitis. furthermore, increasing amounts and levels of serological antibodies such as asca, antilaminaribioside , antichitobioside , antimannobioside , antilaminarin and antichitin associate with disease behavior and surgery, and may aid in the prognosis of crohn's disease. low serum levels of vitamin d are associated with crohn's disease. further studies are required to determine the significance of this association. comparison with ulcerative colitis the most common disease that mimics the symptoms of crohn's disease is ulcerative colitis, as both are inflammatory bowel diseases that can affect the colon with similar symptoms. it is important to differentiate these diseases, since the course of the diseases and treatments may be different. in some cases, however, it may not be possible to tell the difference, in which case the disease is classified as indeterminate colitis. diagnostic findings crohn's diseaseulcerative colitis terminal ileum involvementcommonlyseldom colon involvementusuallyalways rectum involvementseldomusually (95%) involvement around the anuscommon seldom bile duct involvementno increase in rate of primary sclerosing cholangitishigher rate distribution of diseasepatchy areas of inflammation (skip lesions)continuous area of inflammation endoscopydeep geographic and serpiginous (snake-like) ulcers continuous ulcer depth of inflammationmay be transmural, deep into tissues shallow, mucosal stenosiscommonseldom granulomas on biopsymay have non-necrotizing non-peri-intestinal crypt granulomas non-peri-intestinal crypt granulomas not seen differential diagnosis other conditions with similar symptoms as crohn's disease includes intestinal tuberculosis, behçet's disease, ulcerative colitis, nonsteroidal anti-inflammatory drug enteropathy, irritable bowel syndrome and celiac disease. irritable bowel syndrome is excluded when there are inflammatory changes. celiac disease cannot be excluded if specific antibodies (anti-transglutaminase antibodies) are negative, nor in absence of intestinal villi atrophy. management main article: management of crohn's disease management crohn's diseaseulcerative colitis mesalazineless usefulmore useful antibioticseffective in long-termgenerally not useful surgeryoften returns following removal of affected partusually cured by removal of colon there is no cure for crohn's disease and remission may not be possible or prolonged if achieved. in cases where remission is possible, relapse can be prevented and symptoms controlled with medication, lifestyle and dietary changes, changes to eating habits (eating smaller amounts more often), reduction of stress, moderate activity, and exercise. surgery is generally contraindicated and has not been shown to prevent relapse. adequately controlled, crohn's disease may not significantly restrict daily living. treatment for crohn's disease involves first treating the acute problem and its symptoms, then maintaining remission of the disease. lifestyle changes certain lifestyle changes can reduce symptoms, including dietary adjustments, elemental diet, proper hydration, and smoking cessation. patients with crohn's disease are very interested in diet. recent reviews underlined the importance to adopt diets that are best supported by evidence, even if little is known about the impact of diets on these patients. diets that include higher levels of fiber and fruit are associated with reduced risk, while diets rich in total fats, polyunsaturated fatty acids, meat, and omega-6 fatty acids may increase the risk of crohn's. maintaining a balanced diet with proper portion control can help manage symptoms of the disease. eating small meals frequently instead of big meals may also help with a low appetite. a food diary may help with identifying foods that trigger symptoms. despite the recognized importance of dietary fiber for intestinal health, some people should follow a low residue diet to control acute symptoms especially if foods high in insoluble fiber cause symptoms, e.g., due to obstruction or irritation of the bowel. some find relief in eliminating casein (a protein found in cow's milk) and gluten (a protein found in wheat, rye and barley) from their diets. they may have specific dietary intolerances (not allergies), for example, lactose. fatigue can be helped with regular exercise, a healthy diet, and enough sleep, and for those with malabsorption of vitamin b12 due to disease or surgical resection of the terminal ileum, cobalamin injections. smoking may worsen symptoms and the course of the disease, and stopping is recommended. alcohol consumption can also worsen symptoms, and moderation or cessation is advised. medication acute treatment uses medications to treat any infection (normally antibiotics) and to reduce inflammation (normally aminosalicylate anti-inflammatory drugs and corticosteroids). when symptoms are in remission, treatment enters maintenance, with a goal of avoiding the recurrence of symptoms. prolonged use of corticosteroids has significant side-effects; as a result, they are, in general, not used for long-term treatment. alternatives include aminosalicylates alone, though only a minority are able to maintain the treatment, and many require immunosuppressive drugs. it has been also suggested that antibiotics change the enteric flora, and their continuous use may pose the risk of overgrowth with pathogens such as clostridium difficile. medications used to treat the symptoms of crohn's disease include 5-aminosalicylic acid (5-asa) formulations, prednisone, immunomodulators such as azathioprine (given as the prodrug for 6-mercaptopurine), methotrexate, and anti-tnf therapies and monoclonal antibodies, such as infliximab, adalimumab, certolizumab, vedolizumab, ustekinumab, and natalizumab. hydrocortisone should be used in severe attacks of crohn's disease. biological therapies are medications used to avoid long-term steroid use, decrease inflammation, and treat people who have fistulas with abscesses. the monoclonal antibody ustekinumab appears to be a safe treatment option, and may help people with moderate to severe active crohn's disease. the long term safety and effectiveness of monoclonal antibody treatment is not known. the monoclonal antibody briakinumab is not effective for people with active crohn's disease and it is no longer being manufactured. the gradual loss of blood from the gastrointestinal tract, as well as chronic inflammation, often leads to anemia, and professional guidelines suggest routinely monitoring for this. adequate disease control usually improves anemia of chronic disease, but iron deficiency may require treatment with iron supplements. guidelines vary as to how iron should be administered. besides, other problems include a limitation in possible daily resorption and an increased growth of intestinal bacteria. some advise parenteral iron as first line as it works faster, has fewer gastrointestinal side effects, and is unaffected by inflammation reducing enteral absorption. other guidelines advise oral iron as first-line with parenteral iron reserved for those that fail to adequately respond as oral iron is considerably cheaper. all agree that severe anemia (hemoglobin under 10g/dl) should be treated with parenteral iron. blood transfusion should be reserved for those who are cardiovascularly unstable, due to its relatively poor safety profile, lack of long-term efficacy, and cost. list of drug treatments drug class/name corticosterioids prednisone methylprednisolone budesonide antibiotics metronidazole ampicillin ciprofloxacin 5-asas sulfasalazine mesalamine olsalazine balsalazide immunomodulators azathioprine 6-mercaptopurine cyclosporine tacrolimus methotrexate biologics adalimumab infliximab certolizumab pegol ustekinumab vedolizumab natalizumab risankizumab-rzaa surgery crohn's cannot be cured by surgery, as the disease eventually recurs, though it is used in the case of partial or full blockage of the intestine. surgery may also be required for complications such as obstructions, fistulas, or abscesses, or if the disease does not respond to drugs. after the first surgery, crohn's usually comes back at the site where the diseased intestine was removed and the healthy ends were rejoined; it can also come back in other locations. after a resection, scar tissue builds up, which can cause strictures, which form when the intestines become too small to allow excrement to pass through easily, which can lead to a blockage. after the first resection, another resection may be necessary within five years. for patients with an obstruction due to a stricture, two options for treatment are strictureplasty and resection of that portion of bowel. there is no statistical significance between strictureplasty alone versus strictureplasty and resection in cases of duodenal involvement. in these cases, re-operation rates were 31% and 27%, respectively, indicating that strictureplasty is a safe and effective treatment for selected people with duodenal involvement. postsurgical recurrence of crohn's disease is relatively common. crohn's lesions are nearly always found at the site of the resected bowel. the join (or anastomosis) after surgery may be inspected, usually during a colonoscopy, and disease activity graded. the "rutgeert's score" is an endoscopic scoring system for postoperative disease recurrence in crohn's disease. mild postsurgical recurrences of crohn's disease are graded i1 and i2, moderate to severe recurrences are graded i3 and i4. fewer lesions result in a lower grade. based on the score, treatment plans can be designed to give the patient the best chance of managing the recurrence of the disease. short bowel syndrome (sbs, also short gut syndrome or simply short gut) is caused by the surgical removal of part of the small intestine. it usually develops in those patients who have had half or more of their small intestines removed. diarrhea is the main symptom, but others may include weight loss, cramping, bloating, and heartburn. short bowel syndrome is treated with changes in diet, intravenous feeding, vitamin and mineral supplements, and treatment with medications. in some cases of sbs, intestinal transplant surgery may be considered; though the number of transplant centres offering this procedure is quite small and it comes with a high risk due to the chance of infection and rejection of the transplanted intestine. bile acid diarrhea is another complication following surgery for crohn's disease in which the terminal ileum has been removed. this leads to the development of excessive watery diarrhea. it is usually thought to be due to an inability of the ileum to reabsorb bile acids after resection of the terminal ileum and was the first type of bile acid malabsorption recognized. microbiome modification the use of oral probiotic supplements to modify the composition and behaviour of the gastrointestinal microbiome has been researched recently to understand whether it may help to improve remission rate in people with crohn's disease. however only 2 controlled trials were available in 2020, with no clear overall evidence of higher remission nor lower adverse effects, in people with crohn's disease receiving probiotic supplementation. mental health crohn's may result in anxiety or mood disorders, especially in young people who may have stunted growth or embarrassment from fecal incontinence. counselling as well as antidepressant or anxiolytic medication may help some people manage. as of 2017 there is a small amount of research looking at mindfulness-based therapies, hypnotherapy, and cognitive behavioural therapy. alternative medicine it is common for people with